nasa scientific and technical aerospace reports phần 2 pdf

20050169653 Paderborn Univ., Germany
Broadband, Dual Polarised Microstrip Antennas with Improved Beam Forming and Gain Capabilities
Schwenzfeier, Eva; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 120-123; In
English; See also 20050169565; Copyright; Avail: Other Sources
Proximity-coupled antennas like microstrip antennas in general exhibit only a small bandwidth. Different attempts have
been made to increase the bandwidth of microstrip antennas, including the use of thicker substrates, of parasitic elements and
of impedance-matching networks. Although the bandwidth may be increased for the reception of one polarisation, the results
achieved in prior art are not sufficient for DTH (Direct-To-Home) satellite reception. Adual polarised antenna is required from
10.70GHz to 12.75 GHz (relative bandwidth 17.5%). Extensive research in our department led to a special kind of broadband
proximity-coupled and dual polarised antenna. This two-layers configuration is characterized by a simple structure. Based on
this antenna, two novel microstrip antennas were developed which additionally guarantee beam forming and increase gain.
These improved antennas are suitable in antenna arrays to reduce the number of elements and to simplify the feeding network.
Another more often used DTH reception unit is a combination of a parabolic reflector, a feedhorn and a LNB (Low Noise
Block Converter). As illustrated in, it is preferable to avoid the transition loss from hollow waveguide, i.e. the feedhorn, to
planar waveguide technology, i.e. the LNB, by replacing the feedhorn with a single microstrip antenna. An improvement of
beam forming hence is very important for the illumination of the reflector. Therefore, the two novel antenna elements are the
main issue of this contribution.
Author
Broadband; Polarized Electromagnetic Radiation; Microstrip Antennas; Beamforming
20050169659 Chan Technologies, Inc., Kirkland, Quebec, Canada
A Circularly Polarized Waveguide Array for LEO Satellite Communications
Chan, K. K.; Marcoux, F.; Forest, M.; Martins-Camelo, L.; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 154-157; In English; See also 20050169565; Copyright; Avail: Other Sources
The development of a low profiled, circularly polarized waveguide array for LEO satellite communications is presented.
Due to the large quantities of spacecraft forming the LEO constellation, the design of such an array requires a low cost
approach. The array operates from 12.95 to 14.50 GHz and is designed to have an active match of better than 25 dB across
the band. The array is fed by a compact reactive waveguide beamforming network, which dictates the need for well-matched
radiating elements. To provide beam zooming capability, the element excitations are controlled to generate different orbit
location dependent beams. Circular polarization is achieved by means of a meander-linpolarizer. Design and test of this
antenna are discussed in the following sections.

Author
Waveguides; Circular Polarization; Arrays; Low Earth Orbits; Satellite Communication
20050169666 Queensland Univ., Saint Lucia, Australia
Development and Performance of an L-Band Phased Antenna for Mobile Satellite Communications
Karmakar,N. C.; Bialkowski, M. E.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 158-161; In English; See also 20050169565; Copyright; Avail: Other Sources
Recent years have witnessed an introduction of a large number of mobile satellite (MSS) communications systems. These
include a global GEO MSS system,inmarsat, and domestic GEO MSS systems such as North-American AMSC, Japan’s
N-Star and the Australian Mobilesat. At present, two types of antennas can be used to access GEO MSS services. They include:
(1) fixed position antennas, which are used with portable transceivers, and (2) fully mobile antennas such as those installed
on a land vehicle.The fixed position antennas arerelativelyeasytodesign,astheyhave to meet a moderate (approximately7%)
operational bandwidth and a medium (about 10dBi) gain. There are a number of complete portable systems in the commercial
market that include both a transceiver and an antenna. One inconvenience of portable systems is that they require the user be
stationary with respect to the ground. This inconvenience can be overcome with a mobile antenna system. The design of such
a system is more challenging as new features associated with mobility have to be incorporated. This paper presents the
development and performance of a circular phased array antenna for land-vehicle mobile satellite communications. This
antenna is specifically aimed for use with the Australian MSS, Mobilesat. However, it can easily be modified for use with the
other L-band GEO MSS systems.
Author
Antenna Design; Performance Prediction; Mobile Communication Systems; Satellite Communication
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20050169668 Northwestern Univ., Evanston, IL, USA
A Dual-Band Antenna for Cellular Applications: Influence of Plastic Embedding
Vasilyeva, Elena; Taflove, Allen; Navsariwala, Umesh; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 108-111; In English; See also 20050169565; Copyright; Avail: Other Sources
With an increasing demand for cellular phones operating at two frequency bands, several new antenna designs have been
proposed. Recently, a dual-band (GSM and DCS) antenna design using three elements with one feed point was proposed. For
the elements not clad by plastic, the radiation patterns were shown to be basically omnidirectional (though maximum radiation
directions were not in the horizontal plane), and the antenna was tunable by adjusting the length of the wire elements. In this
paper, we report FDTD modeling results for a practical situation wherein the wire elements are formed in a plastic rod. Our

modeling study indicates a large shift of the antenna’s radiation pattern in the elevation plane. This shift likely negates the
usefulness of the design.
Author
Antenna Design; Cladding; Plastics; Electrical Insulation
20050169669 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, USA
A Dual Polarization, Active, Microstrip Antenna for an Orbital Imaging Radar System Operating at L-Band
Kelly, Kenneth C.; Huang, John; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 162-165; In English; See also 20050169565; Copyright; Avail: Other Sources
A highly successful Earth orbiting synthetic antenna aperture radar (SAR) system, known as the SIR-C mission, was
carried into orbit in 1994 on a U.S. Shuttle (Space Transportation System) mission. The radar system was mounted in the cargo
bay with no need to fold, or in any other way reduce the size of the antennas for launch. Weight and size were not limited
for the L-Band, C-Band, and X-Band radar systems of the SIR-C radar imaging mission; the set of antennas weighed 10,500
kg, the L-Band antenna having the major share of the weight. This paper treats designing an L-Band antenna functionally
similar to that used for SIR-C, but at a fraction of the cost and at a weight in the order of 250 kg. Further, the antenna must
be folded to fit into the small payload shroud of low cost booster rocket systems. Over 31 square meters of antenna area is
required. This low weight, foldable, electronic scanning antenna is for the proposed LightSAR radar system which is to be
placed in Earth orbit on a small, dedicated space craft at the lowest possible cost for an efficient L-Band radar imaging system.
This LightSAR spacecraft radar is to be continuously available for at least five operational years, and have the ability to map
or repeat-map any area on earth within a few days of any request. A microstrip patch array, with microstrip transmission lines
heavily employed in the aperture and in the corporate feed network, was chosen as the low cost approach for this active
dual-polarization, 80 MHz (6.4%) bandwidth antenna design.
Author
Polarization (Waves); Microstrip Antennas; Antenna Design; Imaging Techniques
20050169675 University of Central Florida, Orlando, FL, USA
A High Efficiency L-Band Microstrip Antenna
Faiz, M. M.; Wahid, P. F.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 272-275;
In English; See also 20050169565; Copyright; Avail: Other Sources
The design of a high efficiency circularly polarized neatly square patch antenna at the L-band is presented. One way to
improve the efficiency of the inherently low efficiency microstrip antennas is to use substrates with a low permittivity. A low
permittivity substrate with epsilon = 1.1028 was obtained by using a combination of Rogers RT/Duroid 5880 and Rohacell

hard foam. The effect ofa 5 mils thick Rogers RT/Duroid 5880 superstrate on the efficiency was also studied. Results of the
antenna efficiency and bandwidth for both the low dielectric substrate and superstrate are presented. The results were obtained
using the IE3D software package and compared with measured results. Efficiencies of the order of 85% for a single patch
element were obtained.
Author
Ultrahigh Frequencies; Microstrip Antennas; Patch Antennas; Substrates; Permittivity
20050169676 Jet Propulsion Lab., California Inst. of Tech., Pasadena, CA, USA
A Dual-polarized Microstrip Subarray Antenna for an Inflatable L-band Synthetic Aperture Radar
Zawadzki, Mark; Huang, John; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 276-279; In English; See also 20050169565; Copyright; Avail: Other Sources
Inflatable technology has been identified as a potential solution to the problem of achieving small mass, high packaging
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efficiency, and reliable deployment for future NASA spaceborne synthetic aperture radar (SAR) antennas. Presently, there
exists a requirement for a dual-polarized L-band SAR antenna with an aperture size of 10m x 3m, a center frequency of
1.25GHz, a bandwidth of 80MHz, electronic beam scanning, and a mass of less than 100kg. The work presented below is part
of the ongoing effort to develop such an inflatable antenna array.
Author
Microstrip Antennas; Antenna Arrays; Inflatable Space Structures; Large Space Structures; Space Based Radar
20050169677 Nippon Electric Co. Ltd., Yokohama, Japan
180 deg/alpha deg Combined Phase Shifter
Nakada, Kuniyoshi; Murumoto, Tsunehisa; Iwata, Ryuichi; IEEEAntennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 218-221; In English; See also 20050169565; Copyright; Avail: Other Sources
Strip line phase shiflers are key devices widely used in phased array antenna application. To avoid the grating-lobes
through a wide range of scanning angle, the element spacing in the array should be less than about lambda/2. In order to
arrange all of the phase shifters in the phased array antenna on a single plane, each phase shifter should be as compact as
possible. The digital phase shifter, composed of cascaded several bit elements (180 deg, 90 deg, 45 deg, 22.5 deg, ), is widely
used for phased array application. For the elements smaller than 90 deg bit, the loaded-line phase shifters are generally used
because of low insertion loss and simplicity. However, using the loaded-line phase shifter, 180 deg phase shift cannot be
obtained in principle. Thus, for the element of 180 deg bit, the switched-line phase shifter is widely used, though it has
disadvantage of its large size and large phase shift deviation within a bandwidth. In this paper, we propose 180 deg/alpha deg

Combined Phase Shifter, which consists of 180 deg switched-line section and arbitrary angle (alpha deg) loaded-line section.
This proposed phase shifter operates as a 2-bit phase shifter, and has both physical and electrical advantages, i.e., its compact
size and small phase shift deviation. This paper presents basic configuration of the proposed phase shifter, and also presents
an example of characteristics in the case of alpha deg = 45 deg calculated by Method of Moment.
Author
Phased Arrays; Antenna Arrays; Phase Shift Circuits
20050169682 Illinois Univ., Urbana, IL, USA
Full Wave Analysis of Microstrip Lines on Anisotropic Inhomogeneous Substrates
Radhakrishnan, Kaladhar; Chew, Weng Cho; IEEE Antennas and Propagation Society International Symposium, Volume 1;
[1999], pp. 230-233; In English; See also 20050169565
Contract(s)/Grant(s): F49620-96-1-0025; N00014-95-1-0872; NSF ECS-93-02145; Copyright; Avail: Other Sources
Recent developments in microwave integrated circuits have led to complex waveguiding structures with multiple
conductors on inhomogeneous substrate which may or may not be anisotropic Several techniques are available for the analysis
of microstrip lines. A generalized technique to study microstrip lines should be able to account for anisotropy in the substrate.
Anisotropy may occur naturally in the substrate or may be artificially induced to improve system performance In this paper,
we use the finite difference formulation to model the microstrip line. The wave equation involving the transverse field
components is discretized resulting in a sparse eigenvalue problem A spatial interpolation scheme is used to evaluate the
contribution from the off-diagonal terms in the permittivity and permeability tensors. It is shown that the two-term
interpolation scheme performs just as well as the more common four-term scheme. Direct spectral decomposition of the matrix
is expensive for complicated waveguiding structures with large matrices. However, by exploiting the sparsity of the matrices,
it is possible to solve for the eigenpairs much more efficiently. This is accomplished using the bi-Lanczos algorithm.
Author
Microstrip Transmission Lines; Anisotropy; Wave Equations; Homogenizing; Substrates
20050169686 Arizona State Univ., Tempe, AZ, USA
Analysis of HF Antennas on a Helicopter in the Presence of a Stratified Ground
Han, Dong-Ho; Polycarpou, Anastasis C.; Balanis, Constantine A.; IEEE Antennas and Propagation Society International
Symposium, Volume 1; [1999], pp. 496-499; In English; See also 20050169565; Copyright; Avail: Other Sources
Analysis of antennas on a helicopter airframe including the surrounding environment, such as the ground, will provide
much more reliable radiation characteristics for communication rink budget predictions. In order to account for all reflections
and diffractions from the airframe, as well as those from a stratified ground, a full-wave analysis should be used. Since the

exact Green’s function for a stratified ground is available, the radiation problem of a helicopter above the ground reduces to
a problem of finding the total equivalent source in the presence of the ground. Furthermore, if the observation points are
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confined only in the upper hemisphere, then the asymptotic solution for the radiated field due to the source can be obtained
by using the Reflection Coefficient Method (RCM) or Norton’s approximation. In this paper, HF antennas, such as a 14-ft
towel-bar and a 24-ft inverted-L on the AH-64 (Apache) full-scale helicopter, are analyzed in the presence of a stratified
ground. In particular, the ground influence on the radiation pattern is investigated using the Finite Element Method (FEM) in
conjunction with Norton’s approximation. Therefore, the radiated field contains not only the space wave but also the surface
wave which is important for a short observation distance. The lossy ground is defined by its relative permittivity and electric
conductivity.
Derived from text
High Frequencies; Antenna Design; Airframes; Stratification; AH-64 Helicopter
20050169688 Cheng-Shiu Univ., Taiwan
Inset-Microstrip-Fed Circularly Polarized Microstrip Antennas
Chen, Wen-Shyang; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 260-263; In
English; See also 20050169565; Copyright; Avail: Other Sources
An inset-microstripline-fed microstrip antenna, due to its advantage of one printed step without external matching
network and coplanar design in single-layer substrate, has widely used in integration with other microwave elements and array
design. Most of related designs only using an inset-microstripline feed for achieving linear polarization operation have been
reported. Here, we will first demonstrate novel design of inset-microstripline-fed circularly-polarized microstrip antenna from
corner-truncated patch with an inserted slit. A 50 Ohm matching microstripline is introduced and directly inset to the modified
square microstrip antenna for circular polarization (CP) operation. And, by using much more slits inserted at the
comer-truncated patch boundary, these inserted slits can result in meandering of the excited fundamental-mode patch surface
current path, which effectively lowers the resonant frequency of the modified square patch, similar to the design using four
inserted slits of different lengths at the boundary of a square patch. Results have been obtained that a compact CP operation
for the modified design can be achieved by using an inset microstripline feed. Details of design of inset-microstripline-fed
microstrip antennas are discussed in the Symposium.
Author
Microstrip Antennas; Planar Structures; Circular Polarization
20050169689 National Kaohsiung Inst. of Marine Technology, Koahsiung, Taiwan, Province of China

Single-Feed Circularly Polarized Triangular Microstrip Antennas
Lu, Jui-Han; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 264-267; In English;
See also 20050169565; Copyright; Avail: Other Sources
Recently, many designs of single-feed circularly polarized microstrip antennas with square or circular patches have been
reported. It is found that, for both regular-size and compact CP operations, the related designs of microstrip antennas are
largely on square and circular patches. Relatively very few designs for achieving CP operation using triangular microstrip
antennas are available in the open literature. This motivates the present study of novel designs of both regular-size and
compact CP operations of triangular microstrip antennas. For the present, the typical designs of circularly polarized triangular
microstrip antennas that have been reported are the designs using a nearly equilateral-triangular patch or an equilateral-
triangular patch with a slit inserted at the patch edge. In this article, we first demonstrate another promising regular-size CP
design of triangular microstrip antennas with an embedded narrow horizontal slot. And, it is then shown that, by using a cross
slot of unequal slot lengths in place of the embedded horizontal slot, the circularly polarized radiation of the slotted triangular
microstrip antenna can occur at a lower operating frequency. Details of the proposed CP designs of slotted triangular
microstrip antennas are described, and experimental results of the CP performance are presented and discussed.
Author
Circular Polarization; Triangulation; Microstrip Antennas
20050169690 Saitama Univ., Urawa, Japan
Array Antenna Composed of Circularly Polarized Dielectric Resonator Antennas
Haneishi, Misao; Wu, Bing; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 252-255; In English; See also 20050169565; Copyright; Avail: Other Sources
Recently, a dieleclric resonator antenna (DRA) including circularly polarized DRA (CP-DRA) has been studied by many
researchers, since it can be used as an efficient radiator in the high frequency region. A new type of CP-DRA element fed by
an asymmetric cross-slot is proposed here. This type of CP-DRA is probably one of the simplest device for producing circular
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polarization at or near the millimeter-wave region. This paper presents the radiation properties of a new type of CP-DRA
element together with the design technique of DRA array composed of a pair of CP-DRAs. In order to evaluate the
performance, some DRA elements and its arrays were fabricated and tested at X-band. The 3-dB axial-ratio bandwidth
obtained from this new type of DRA array was about 20% at X-band, and it had an extremely broadband performance
compared to that of an usual array antenna. Therefore, the DRA array proposed here is considered to be an effective model
as a broadband circularly polarized array.

Author
Antenna Arrays; Resonators; Circular Polarization
20050169691 Centre National de la Recherche Scientifique, Valbonne, France
Array of Coupled Oscillators Generating Circular Polarization
Dussopt, L.; Laheurte, J-M.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 268-271; In English; See also 20050169565; Copyright; Avail: Other Sources
Coupled-oscillator arrays have been widely used for linear polarization but have not been implemented in communication
systems involving circular polarization. This paper presents an array of four coupled oscillators using linearly polarized
elements to generate circular polarization (CP). An array to generate CP with linearly polarized elements has been extensively
described. The array consists in four patch elements with 0 deg, 90 deg, 180 deg, 270 deg arrangement both for angular
orientation and feed phase. This array has shown good CP quality for a wide axial ratio bandwidth. The coupling circuit is
designed so that a 0 deg, 90 deg, 180 deg, 270 deg arrangement for the oscillator phases is obtained. Since stable steady-state
operation can not be achieved for this phase arrangement with classical mutual coupling, the oscillators are phase-locked in
a loop by unidirectional coupling provided by amplifiers. This new arrangement is theoretically investigated and validated by
measurements of CP radiation patterns.
Author
Oscillators; Arrays; Circular Polarization; Antenna Components
20050169692 Cheng-Shiu Univ., Taiwan
Small Circularly Polarized Microstrip Antennas
Chen, Wen-Shyang; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 256-259; In
English; See also 20050169565; Copyright; Avail: Other Sources
For satisfying requirement of compactness, the related designs with circularly polarized radiation have been reported. In
these designs, a modification element for achieving a compact circular polarization (CP) operation is introduced by using a
cross-slot cut in the circular microstrip patch center or two pairs of narrow slots inset at the boundary of the square microstrip
patch. It can be noted that these CP designs are used by a cross slot or two pairs narrow slot of owing unequal length to split
the antenna’s fundamental mode into two near-degenerate resonant modes with equal amplitude and 90 deg. phase difference.
In practical application, this makes it possible to be less freedom degree of fabrication. It is inconvenient to carry out
post-manufacturing free-tuning in such designs to compensate for the possible fabrication errors and substrate material
tolerances. Here, we demonstrate two configuration to perform the small CP operation with much relaxed manufacturing
tolerances. One is a peripheral-cuts circular microstrip antenna with a equal arm-length cross slot, and the other is a

comer-truncated square microstrip antenna with four equal arm-length bent slots. With the peripheral cuts or truncated corners
in the microstrip patch, it can be splitted antenna’s fundamental mode into two near degenerate orthogonal modes with
quadrature phases. Also with a equal arm-length cross slot or four equal ann-length bent slots embedded in the microstrip
patch, the proposed microstfip antenna is expected to lengthen their two near degenerate orthogonal modes as compared to
the peripheral-cuts circular microstrip antenna or corner-truncated square microstrip antenna. Typical results of the proposed
design for the small CP antennas will be discussed in the Symposium.
Author
Microstrip Antennas; Polarized Radiation; Design Analysis; Void Ratio
20050169701 Da-Yeh Univ., Taiwan
Cylindrical and Rectilinear Microstrip Lines with Indented Grounds
Hsu, Chung-I G.; Kiang, Jean-Fu; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 322-325; In English; See also 20050169565; Copyright; Avail: Other Sources
Microstrip lines have been the most popular interconnects between microwave devices. Results and applications of
various microstrip structures that are rectilinear in nature can be found in the literature, for example). Wedge-supported
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microstrip structures are widely utilized in the conformal antenna system constructed in aircraft and missiles. The analysis in
does not allow the presence of the superstrate. The structures considered in are restricted to the case where conducting strips
are printed on the surface of the single-layered substrate. Broadside-coupled microstrip structures cannot be tackled in. Also,
the outer shielding conductors are not considered in beth and. In this research, we will extend the mode-matching technique
developed in to handle the structure that consists of a multilayered background medium, optional inner and/or outer shielding
conductors, and indents or cavities on the shielding conductors. The indents are usually due to undesired surface imperfection
in the fabrication process, whereas the cavities can be used to provide additional degrees of freedom in designing a
transmission-lin.e system.
Derived from text
Microstrip Transmission Lines; Cylindrical Bodies; Microwave Equipment
20050169703 National Taiwan Univ., Taipei, Taiwan, Province of China
Antenna Gain and Scattering Measurement Using Reflective Three-Antenna Method
Lu, Hsin-Chia; Chu, Tah-Hsiung; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 374-377; In English; See also 20050169565; Copyright; Avail: Other Sources
Three-antenna method is a technique to measure the antenna gain without using a reference antenna. Since it operates in

a transmission-type arrangement, a long return cable is required. Several methods were then developed to eliminate the return
cable by using the radar cross section (RCS) measurement method. The advantages of this method are described. A
measurement method based on RCS measurement concept and antenna scattering matrix is developed. It can not only measure
the antenna gain, but also derive the structural scattering characteristics and antenna input impedance from the measurement.
However, it requires a complicated polarimetric calibration procedure for the measurement system. In this paper, a novel
method is proposed to combine the concepts of three-antenna method and RCS measurement method to measure the antenna
gain and its structural scattering characteristics without involving the reference antenna or polarimetric calibration. In this
method, the measurement arrangement including the transmitting and receiving antennas is considered as a two-port network
with reference planes at the input port for each antenna as shown. By connecting three different known terminators at the
receiving antenna port and measure the reflection coefficients at the transmitting antenna port, the scattering parameters of this
two-port network can be derived. They are shown to be related to the product of two antennas’ gain. Therefore one can follow
the three-antenna method to find the gain of each antenna. In addition, the structural scattering characteristics of each antenna
can be solved.
Derived from text
Antenna Gain; Reflectance; S Matrix Theory; Antenna Design
20050169707 Alexandria Univ., Egypt
Frequency Hopped-Chirp Modulation (FH-CM) for Multi-User Signaling in Multipath Dispersive Media
El-Khamy, Said E.; Shaaban, Shawki E.; Thabet, Essam A.; IEEE Antennas and Propagation Society International
Symposium, Volume 1; [1999], pp. 396-399; In English; See also 20050169565; Copyright; Avail: Other Sources
Chirp signals are categorized as spread-spectrum signals and have good advantages in interference rejection. The use of
matched chirp modulation (MCM) for efficient digital signaling in dispersive communication channels has also been
considered by E1-Khamy et al. Chirp modulation has also been considered for multi-user applications. New forms of
multi-user chirp modulation (M-CM) signals that are characterized by the same power as well as the same bandwidth have
been introduced recently by the authors. In this paper, we investigate the combination of frequency-hopping (FH)
spread-spectrum techniques with M-CM to produce a multiple-access technique that is characterized by good performance in
dispersive and fading propagation media. The considered frequency-hopped chirp modulation (FH-CM) is investigated in
details and its performance is shown to highly outperform that of M-CM.
Derived from text
Chirp Signals; Frequency Hopping; Modulation; Multipath Transmission; Mathematical Models
20050169710 California Univ., Los Angeles, CA, USA

Optimal Design of the Generalized Three-Parameter Aperture Distribution by the Emperor-Selective Genetic
Algorithm
Lu, Yilong; Rahmat-Samii, Yahya; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 422-425; In English; See also 20050169565; Copyright; Avail: Other Sources
This paper presents a novel approach for automatic design of optimal aperture field distribution based on the versatile
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three-parameter (3-P) model for elliptical (or circular) aperture antennas. This model is very useful for the design of aperture
type antennas such as reflector antennas, lenses, and large planar arrays. In application, the challenge is how to find those
parameters to give the optimal aperture distribution so as to achieve the desired radiation characteristics of aperture antennas.
For example, one may desire high directivity, low sidelobe level (SLL), high beam efficiency, and low spillover for a shaped
reflector antenna. In order to make the best use of the 3-P model for optimal design of aperture distribution, the
Emperor-Selective based genetic algorithm (EMS-GA) is used to find the three parameters. Genetic Algorithms (GAs) are
scholastic optimization technique based on the concept of biological genetics and natural selection and they have a very wide
application in optimization of engineering problems. However, the standard GAs, which based on randomized-mating and
binary-crossover, suffer from one major drawback and they are usually unable to move the search to areas outside the space
of the initial population. In our GA, the more effective Emperor-Selective (EMS) mating scheme and floating number
interpolating and extrapolating linear crossover are used for fast solutions. Simulations show that only a few generations may
be used to achieve satisfactory results.
Author
Apertures; Distribution Functions; Genetic Algorithms; Design Analysis
20050169711 Nebraska Univ., Lincoln, NE, USA
Stationary Solutions for the Rough Surface Radar Backscatter Cross Sections Based on a Two Scale Full Wave
Approach
Bahar, Ezekiel; Crittenden, Paul; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 510-513; In English; See also 20050169565; Copyright; Avail: Other Sources
Using a full wave approach, the rough surface radar backscatter cross sections are expressed as weighted sums of two
cross sections. Tile radar cross sections associated with the larger scale surface are reduced by a factor equal to the square of
tile characteristic function of the smaller scale surface (that rides upon the larger scale surface). The Bragg scatter
contributions front the small scale surface are modulated by the slopo_ of the large scale surface. The back scatter cross
sections are obtained by regarding the rough surface as an ensemble of patches of random rough surfaces with arbitrary

orientations. It. is shown that the full wave solutions are stationary over a wide range of patch sizes. The patches are
characterized by tile spectral wavenumber that separates the large scale surface from the small scale surface. The mean square
heights and slopc_ of the large (and small) scale surfaces depend on the choice of patch sizes.
Author
Backscattering; Mean Square Values; Radar Cross Sections
20050169713 Georgian Technical Univ., Tbilisi, Georgia
Running Power Spectrum of Pulsed Radiation in an Absorptive Randomly Inhomogeneous Media
Jandieri, G. V.; Pirtskhalaishvili, N. G.; Jandieri, V. G.; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 538-541; In English; See also 20050169565; Copyright; Avail: Other Sources
To the problem of pulse signal propagation in a chaotically inhomogeneous media is devoted a great number of papers.
The behavior of the Running power spectrum (RPS) of pulsed radiation in a weakly dispersive chaotically nonstationary media
was investigated at one-dimensional spatial-temporal permittivity fluctuations using statistical moment method. The
investigations of the features of the normalized RPS in absorptive random medium at both one-dimensional spatial-temporal
dielectric permittivity and conductivity fluctuations is of interest.
Derived from text
Pulsed Radiation; Pulse Duration; Electromagnetic Radiation
20050169718 NTT Mobile Communications Network, Inc., Japan
Dual Frequency Resonant Base Station Antennas for PDC Systems in Japan
Ebine, Yoshio; IEEEAntennas and Propagation Society International Symposium, Volume 1; [1999], pp. 564-567; In English;
See also 20050169565; Copyright; Avail: Other Sources
Cellular mobile communication systems are being successfully developed all over the world. To accommodate the
increase in the number of mobile phone subscribers, multiple systems accessing different frequency bands are being employed.
In 1993, PDC (personal digital cellular) systems started operation in the frequency bends of 800MHz and 1500MHz, in Japan.
The PDC systems of NTTDoCoMo in Japan also use dual frequency bands, accordingly, the base station antennas used in the
PDC system must be dual frequency resonant to reduce the cost and space required for the antenna. This paper presents
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commercial dual frequency resonant (DF) base station antenna (BSA) and an operation mechanism for a remote-controlled
beam tilting system in the vertical plane.
Derived from text
Pulse Communication; Japan; Antenna Design; Mobile Communication Systems

20050169719 Nippon Telegraph and Telephone Public Corp., Japan
Advanced Base Station Antennas for Personal Handy-phone System (PHS) in Japan
Hori, Toshikazu; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 572-575; In
English; See also 20050169565; Copyright; Avail: Other Sources
The Personal Handy-phone System (PHS) is one of the micro-cellular systems now in service in Japan. This system
mostly uses rod antennas at the base stations because of their easy installation and low cost; they are usually placed on top
of public telephone boxes and utility poles, at the top of towers installed on telephone offices, and on the ceiling of
underground shopping area or in buildings, and so on. Obviously antenna heights and installation conditions differ widely.
Street microcells are formed in urban areas because most antennas arc surrounded by buildings. Some antennas may be sited
on towers and not all sites have the same surroundings, so the base station antennas must offer a wide variety of radiation
patterns. Based on a consideration of the propagation characteristics and the installation condition, we have developed several
base station antennas. This paper introduces the design concepts and experimental results of these microcell base station
antennas for PHS. The fabricated rod antennas are tested in a real propagation environment in an urban area. The trials confirm
the validity of our design method and the usefulness of the antennas.
Derived from text
Japan; Telephones; Antenna Design; Fabrication
20050169724 Yokohama National Univ., Japan
Analysis of Patch Antenna with Short Pin by Using Non-Uniform Mesh FDTD
Jiang,Huiling; Arai, Hiroyuki; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 610-613; In English; See also 20050169565; Copyright; Avail: Other Sources
The need for smaller antennas has become increasingly important in recent years because the effect of large scale
integration of electronic components generally isolates the antenna as the most bulky, heavy and obtrusive part of the
equipment. But it is an accepted fact that electrically smaller antennas have narrower bandwidths and poorer efficiencies than
their larger counterparts. This would incur significant power losses and reduce the general efficiency of the receiver as well
as increasing equipment costs. Today more efficient matching techniques are available. For example, for a center fed patch
antenna, post pins which were are usually used around the feed pin for matching purpose. This study was proceeded by
experimentally way mainly till now. In design of small antennas, optimization of parameters by using numerical simulation
is necessary. In early works, numerical simulation by using wire-mesh method and diakoptic theory has been used. Because
it is very difficult to deal with the patch structure and wire element simultaneously, numerical analysis of matching technique
by using same analysis method haven’t been reported yet. In this paper, we calculated the center fed patch antenna which has

two post pins by using FDTD method. To improve the computation efficiency, the FDTD analysis by using non-uniform mesh
is used during the simulation. By changing the structure of matching element, examination of matching technique of low
profile antenna is carried out in this paper.
Author
Patch Antennas; Finite Difference Theory; Large Scale Integration; Numerical Analysis
20050169725 MacQuarie Univ., Sydney, Australia
FDTD Analysis of an Inclined Microstrip Patch Antenna, Considering Field Singularity at the Edges
Esselle, Karu P.; Foroughipour, Mahmoudreza; IEEE Antennas and Propagation Society International Symposium, Volume 1;
[1999], pp. 606-609; In English; See also 20050169565; Copyright; Avail: Other Sources
A rectangular microstrip patch antenna, inclined to the FDTD grid by 45 deg, is accurately analysed using enhanced
FDTD equations for diagonal metal edges. The enhanced equations, derived by considering the singular nature of
electromagnetic fields at sharp metal edges, properly model the patch with less number of FDTD cells. The same inclined
patch antenna is modelled using two existing techniques as well, namely staircase and split-cell models, for comparison with
enhanced equations. The resonance frequencies and the frequency response of the patch are computed using these three
techniques, and are compared with a very accurate reference, which is obtained by analyzing a similar patch but kept parallel
to a much finer grid. It is found that the enhanced equations give extremely accurate results consistently, without any
62
noticeable computing overhead. For example, the accuracy of the first resonance frequency using the enhanced equations is
1.1%, and that using the staircase and split-cell models is 7.1% and 3.5%, respectively. The enhanced equations are very stable,
and are time-stepped at the maximum Courant limit in all simulations without any problems.
Author
Finite Difference Time Domain Method; Microstrip Antennas; Patch Antennas; Antenna Radiation Patterns; Electromagnetic
Fields; Edges; Metal Surfaces
20050169726 Michigan Univ., Ann Arbor, MI, USA
Effects of the Fast Multipole Method (FMM) Parameters on Radar Cross Section Computations
Sertel, K.; Volakis, J. L.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 624-627;
In English; See also 20050169565; Copyright; Avail: Other Sources
The Method of Moments (MoM) has been successfully applied to all types of electromagnetic scattering and radiation
problems. As is well known, conventional MoM techniques lead to fully populated interaction matrices. This aspect limits the
electrical size of the problem that can be solved on a given computer with limited memory. Recently introduced fast methods,

such as the adaptive integral method (AIM) and fast multipole method (FMM), provide for reduced memory and CPU
requirements. In this paper we consider the implementation of FMM to MoM matrices associated with 2nd order curvilinear
elements. Particular emphasis is given on the convergence properties and accuracy of FMM acceleration schemes. It is
demonstrated that preconditioning is often essential when dealing with FMM matrices generated from curvilinear element
implementations. Also, choices of lower order multipole expansions can lead to much faster speeds but lower accuracy.
Author
Radar Cross Sections; Multipoles; Method of Moments
20050169732 Raytheon Systems Co., Sudbury, MA, USA
A Milstar Low Profile Antenna
Chang, Y.; Sarcione, M.; Beltran, F.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 684-687; In English; See also 20050169565; Copyright; Avail: Other Sources
A low profile antenna/pedestal system for the Milstar program was developed at Raytheon under an Air Force contract.
The system was designed to have minimum intrusion inside the aircraft and no protrusion outside the aircraft so that the
radome is flush to the fuselage. The main drivers of this antenna design include low cost, minimum height, and high
efficiencies for both K-band (20.2 -21.2 GHz) and Q-band (43.5 - 45.5 GHz). The approach Raytheon chose was a 20 inch
wide 9.5 inch high elliptical offset dual-shaped Gregorian reflector with a compact concentric feed as shown. The main
challenge of such an elliptical aperture design is optimizing the antenna efficiency. Shaping approaches reported by P-S. Kildal
offer an excellent solution to this problem. These approaches were used to synthesize the main reflector and subreflector and
to analyze the antenna performance. After a thorough tradeoff study, a reflector configuration meeting the design driving
factors as shown was chosen. This figure includes front and side views with ray tracing lines to indicate the energy spread.
Despite blockage by the feed and the subreflector, this configuration offers the maximum effective antenna aperture under the
height constrain. In synthesizing the reflector surfaces, a -15 dB taper was chosen at the subreflector edge to minimize the
spillover loss. To maximize the illumination efficiency, a -3 dB edge taper on the antenna aperture was chosen. Since circular
polarization is required for both K- and Q-bands, a compact concentric feed with symmetric feed patterns was selected. The
Q-band feed in the center has a dielectric launching rod, and the feed horn is a multi-mode horn with a 1.05 inch diameter.
A septum polarizer is used to generate circular polarization for Q-band and dielectric vanes are used in the K-band coaxial
waveguide. Typical measured feed patterns are shown.
Derived from text
Antenna Design; Systems Engineering; Dielectrics
20050169734 Vertex Communications Corp., Kilgore, TX, USA

A Dual Band Low PIM Feed System for Cassegrain Applications
Beadle, Mark; Casey, Sean; Schwerdtfeger, Roland; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 696-699; In English; See also 20050169565; Copyright; Avail: Other Sources
Multi-frequency band, multi-function satellite communications antenna systems, and in some instances, limited ground
facilities, have in recent times required complex single aperture feed system designs. The normal approach involves the
inherent frequency selection characteristics of the periodic structure of the corrugated horn. Interesting design problems occur
in the coupling junction at which frequency selection/separation takes place, to ensure complete lossless decoupling between
63
operational frequency bands. More importantly though, maintaining stringent low sidelobe envelope and polarization
discrimination performance consistent with modern satellite communication requirements, have a dramatic effect on the nature
of the design of the horn and the frequency selective coupling junctions. Anumber of computational design routines have been
developed for these junction designs, and refined to offer compliant antenna performance. Typical examples of such designs
are: 2/8 GHz, 4/7/12 GHz, 2/4 GHz, 11/14/18 GHz, 4/12 GHz, 12/20 GHz, all involving adjustable and/or switchable CP/LP
polarization configurations in one form or another. The following briefly describes the more unusual aspects of the 1.75- 1.85
/ 2.2-2.3 GHz and 7.25-7.75 / 7.9-8.4 GHz feed for a 9m Cassegrain having also to comply with a very low level passive
intermodulation products (PIMPs) specification in X-band.
Author
Bands; Frequencies; Antenna Design; Design Analysis; Frequency Distribution
20050169735 Aerospace Corp., El Segundo, CA, USA
An Ultra-Wideband Nested Coaxial Waveguide Feed for Reflector Antenna Applications
Johns, Steven L.; Prata, Aluizio, Jr.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 704-707; In English; See also 20050169565; Copyright; Avail: Other Sources
The idea of using nested coaxial waveguides and cavities for multiband and wideband-applications has been of interest
for many years. The reason for the recurring interest stems from the fact that multiple frequency-scaled coaxial waveguides
can be conveiently nested in the inner conductor of an original coaxial waveguide. With this scheme, several antennas (cups)
can be concentrically located in the same area as the largest coaxial waveguide to accommodate a wide frequency band.
However, due to frequency limitations, practical nesting of coaxial waveguide cups has generally been limited to
multifrequency applications. For wideband operation, the ratio of the outer-to-inner coaxial waveguide conductor radii must
be relatively small, resulting in high reflection coefficients and significant cross-polarized radiation (cx-pol). Also, mutual
coupling between the dicent coaxial waveguide cups adversely affects performance. Several methods using irises and

dielectrics have been employed to handle these limitations, but have seen limited success. A simple alternative method to
reduce these difficulties involves extending the center conductor of the coaxial waveguide past the aperture. This extension
of the center conductor reduces the reflection coefficient of the coaxial waveguides The mode over a large bandwidth, as well
as the mutual coupling between the nested coaxial waveguide cups.
Derived from text
Reflector Antennas; Waveguide Antennas; Cross Polarization
20050169768 General Accounting Office, Washington, DC
LOCAL TV Act: Administrative Funds May No Longer Be Necessary
Apr. 2005; 24 pp.; In English
Report No.(s): PB2005-106266; GAO-05-438; No Copyright; Avail: CASI;
A03, Hardcopy
This is GAO’s third report addressing the LOCAL TV Act’s requirement that GAO perform an annual audit of the (1)
administration of the provisions of the act and (2) financial position of each applicant who receives a loan guarantee under
the act, including the nature, amount, and purpose of investments made by the applicant. Although the LOCAL Television
Loan Guarantee Program (LOCAL TV Program) was implemented in fiscal year 2004, there were no loan guarantee applicants
for GAO to audit. Therefore, this report primarily addresses whether program administration during fiscal year 2004 satisfied
the provisions of the act.
NTIS
Television Systems; Project Management
20050169925 NASA Lewis Research Center, Cleveland, OH, USA, Electronic Industries Association, USA
Digital Audio Radio Broadcast Systems Laboratory Testing Nearly Complete
[2005]; 3 pp.; In English; No Copyright; Avail: CASI;
A01, Hardcopy
Radio history continues to be made at the NASA Lewis Research Center with the completion of phase one of the digital
audio radio (DAR) testing conducted by the Consumer Electronics Group of the Electronic Industries Association. This
satellite, satellite/terrestrial, and terrestrial digital technology will open up new audio broadcasting opportunities both
domestically and worldwide. It will significantly improve the current quality of amplitude-modulated/frequency-modulated
(AM/FM) radio with a new digitally modulated radio signal and will introduce true compact-disc-quality (CD-quality) sound
for the first time. Lewis is hosting the laboratory testing of seven proposed digital audio radio systems and modes. Two of the
proposed systems operate in two modes each, making a total of nine systems being tested. The nine systems are divided into

64
the following types of transmission: in-band on-channel (IBOC), in-band adjacent-channel (IBAC), and new bands. The
laboratory testing was conducted by the Consumer Electronics Group of the Electronic Industries Association. Subjective
assessments of the audio recordings for each of the nine systems was conducted by the Communications Research Center in
Ottawa, Canada, under contract to the Electronic Industries Association. The Communications Research Center has the only
CCIR-qualified (Consultative Committee for International Radio) audio testing facility in North America. The main goals of
the U.S. testing process are to (1) provide technical data to the Federal Communication Commission (FCC) so that it can
establish a standard for digital audio receivers and transmitters and (2) provide the receiver and transmitter industries with the
proper standards upon which to build their equipment. In addition, the data will be forwarded to the International
Telecommunications Union to help in the establishment of international standards for digital audio receivers and transmitters,
thus allowing U.S. manufacturers to compete in the world market.
Derived from text
Broadcasting; Digital Systems; Radio Communication; Telecommunication; Audio Signals
20050170568 Graduate Univ. for Advanced Studies, Japan
VLBI Observation of Narrow Bandwidth Signals from the Spacecraft
Kikuchi, Juyuhiko; Ping, Jinsong; Hong, Xiaoyu; Aili, Yusup; Liu, Qinghui; Mastumoto, Koji; Asari, Kazuyoshi; Tsuruta,
Seiitsu; Kono, Yusuke; Hanada, Hideo, et al.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.; In English; See
also 20050170551; Copyright; Avail: CASI;
A01, Hardcopy; Available from CASI on CD-ROM only as part of the entire
parent document
The lunar gravity field has been investigated by Doppler measurement for the last 40 years. However, the gravity field
of the rim of the Moon was not clearly investigated like the nearside. Over the rim of the Moon, the gravity force from the
Moon acts mainly in the direction perpendicular to line of sight (LOS). So we can t estimate the gravity field precisely only
by Doppler measurements which is sensitive to the direction of LOS. In order to solve this problem, we apply very long
baseline interferometry (VLBI) technique in VRAD (the differential VLBI radio sources) mission of Japanese lunar explorer
SELENE (SELenological and ENgineering Explorer) in addition to a conventional 2-way and newly applied 4-way Doppler
measurements. By measuring the difference of arriving time of the same wave front of a radio signal from the spacecraft (s/c)
at two or more separated antennas, VLBI can precisely determine the position and the velocity of the s/c in the direction
perpendicular to LOS.
Derived from text

Very Long Base Interferometry; Bandwidth; Moon; Gravitational Fields; Radio Sources (Astronomy)
20050170630 Brown Univ., Providence, RI, USA
New Results from the Magellan Bistatic Radar Experiment
Kreslavsky, M. A.; Ford, P. G.; Pettengill, G. H.; Head, J. W.; Lunar and Planetary Science XXXVI, Part 11; [2005]; 2 pp.;
In English; See also 20050170551; Original contains color and black and white illustrations; Copyright; Avail: CASI;
A01,
Hardcopy; Available from CASI on CD-ROM only as part of the entire parent document
Bistatic radar is a powerful tool for studying planetary surfaces. In this technique, the incident signal from a
spacecraft-borne transmitter is directed to the specular point on a planet, and the signal scattered by the surface is received
on the Earth. At microwave frequencies typical planetary surfaces scatter electromagnetic waves quasi-specularly, which
means that the mirror-like reflection component dominates the scattered signal. In this case, the polarization state of the
received echo depends only on the electromagnetic properties (dielectric permittivity and magnetic permeability) of the
surface material (according to Fresnel s equations), thus providing unambiguous constraints on these parameters.
Derived from text
Planetary Surfaces; Microwave Frequencies; Electromagnetic Radiation; Dielectric Permeability; Multistatic Radar
20050170641 NASA Glenn Research Center, Cleveland, OH, USA
Fiber Optic Repair and Maintainability (FORM) Program Progresses
[2005]; 2 pp.; In English; No Copyright; Avail: CASI;
A01, Hardcopy
Advanced aircraft will employ fiber-optic interconnection components to transmit information from airframe and
propulsion sensors to the flight control computers. Although these optical interconnects have been rigorously tested under
laboratory conditions to determine their operating and environmental limits, there is concern as to their repairability and
maintainability when placed in actual service. The Fiber Optic Repair and Maintainability (FORM) flight test program will
provide data to enable designers to improve these fiber-optic interconnection systems for the next generation of aircraft.
65
FORM is identifying critical problems in installing, maintaining, testing, and repairing fiber-optic interconnection systems in
an operational avionics environment. This program is a cooperative Government/industry effort to evaluate optical component
acceptability and installation techniques for aircraft.
Author
Fiber Optics; Optical Interconnects; Communication Equipment; Flight Tests; Aircraft Equipment; Aircraft Communication;

Maintainability
20050170915 Swedish Defence Research Establishment, Linkoeping, Sweden
Communication and Team Performance in BA Teams A Field Study of Breathing Apparatus Firefighters’ Communi-
cation during Rescue Operations
Lindgren, I.; Berggren, P.; Jander, H.; Hirsch, R.; Nov. 2004; 86 pp.; In English
Report No.(s): PB2005-103076; FOI-R-1507-SE; No Copyright; Avail: CASI;
A05, Hardcopy
The lack of guiding principles for the communication during breathing apparatus rescue operations is seen as a problem
by many firefighters. There is a wish to obtain further heuristics for the communication, but there is no agreement concerning
what successful communication is and how it should be achieved. This research aimed through field studies to see how the
BA firefighters and the BA leader communicate with each other. It also aimed to investigate if some answers to what defines
‘good communication’ during BA rescue operations could be found. Through a qualitative analysis of the communication
patterns of two pairs of BA firefighters the impact on the communication made by common ground establishment, team
knowledge and similar phenomena, such as experience of working together, has been investigated. The results illustrate
communicative problems which can occur during a rescue operation and shed light on the gravity of an agreement on what
information should be mediated by the BA firefighters. It is also seen how experience of working together can be suggested
to help the firefighters to communicate efficiently.
NTIS
Human Performance; Rescue Operations; Teams
20050170916 Swedish Defence Research Establishment, Linkoeping, Sweden
BA Rescue Team Performance Exploring Team Situation Awareness, Mental Models, and Team Processes in Breathing
Apparatus Rescues
Fogel, A.; Berggren, P.; Jander, H.; Nov. 2004; 72 pp.; In English
Report No.(s): PB2005-103075; FOI-R-1508-SE; No Copyright; Avail: CASI;
A04, Hardcopy
The current study aimed at investigating the concepts of team situation awareness, mental models, and team processes in
relation to performance in the complex, dynamic environment of breathing apparatus rescues. Data was collected during
exercises at Agesta training center through questionnaires and after action reviews. 28 firemen and 5 instructors participated
in the exercises. Also, a stimulated recall interview was conducted with 2 of the firemen that had participated in one of the
exercises. The different data collection methods all indicated that well- developed mental models or a high degree of pre-task

knowledge affected performance in a positive way. Moreover, a multiple regression analysis showed that both pre-task
knowledge and team processes significantly can predict performance. The results of the analysis of team situation awareness
in relation to performance were fairly ambiguous. Therefore, further research is needed to establish the relation between these
concepts in the domain at matter.
NTIS
Human Performance; Rescue Operations; Teams
20050170921 Swedish Defence Research Establishment, Linkoeping, Sweden
Quality of Service in Ad Hoc Networks by Priority Queuing
Tronarp, O.; Jan. 2004; 52 pp.; In English
Report No.(s): PB2005-102878; FOI-R-1156-SE; No Copyright; Avail: CASI;
A04, Hardcopy
The increasing usage of information technology in military affairs raises the need for robust high capacity radio networks
that will be used to provide several different types of services, such as group calls and situation awareness services. As all
services have specific demands on packet delays and packet losses in order to be fully functional, there is a need for a
quality-of-service (QoS) mechanism in the network. In this report the authors examine the possibility of providing a QoS
mechanism in ad hoc networks by using priority queues. The study includes two different queuing schemes, namely fixed
priority queuing and weighted fair queuing. The performance of the two queuing schemes is evaluated and compared with
respect to their ability to provide differentiation in network delay, i.e. provide high-priority traffic with lower delays than
66
low-priority traffic. The study is mainly done by simulations, but for fixed priority queuing the authors also derive an analytical
approximation of the network delay.
NTIS
Communication Networks; Information Systems; Military Technology
20050170972 Arkansas Univ., Fayetteville, AR, USA
Ground Penetrating Radar in Sedimentary Rocks
Lee, J. B.; Sahai, S. K.; Paxton, S. T.; Hadaway, S.; Lunar and Planetary Science XXXVI, Part 12; [2005]; 2 pp.; In English;
See also 20050170942; Original contains color and black and white illustrations; Copyright; Avail: CASI;
A01, Hardcopy;
Available from CASI on CD-ROM only as part of the entire parent document
Ground Penetrating Radar (GPR) is used to view the subsurface of soil and rock layers. GPR uses electromagnetic waves,

in the radio frequency range, to investigate shallow subsurfaces. The wave is produced by a transmit antenna, scattering on
layers of varying impedance, then recorded by a receive antenna. Since metal objects can greatly influence the quality of the
GPR data, Oklahoma State University’s GPR (the Pulse EKKO 100) is designed with a minimal amount of metal. The Pulse
EKKO 100 comes with a PVC support system for the antennae instead of a metal support system. Another way to reduce noise
in the data is to use fiber optic cable, instead of copper cable. The cable is required to send the transmit signal, send the receive
signal, and to retrieve the data. Fiber optic cable greatly reduces noise, but is expensive and fragile. Some of the basic
components of a Pulse EKKO 100 are shown. Additional information is included in the original extended abstract.
Author (revised)
Ground Penetrating Radar; Radar Equipment; Radar Geology; Planetary Geology
20050171019 NASA Lewis Research Center, Cleveland, OH, USA
Implications of ACTS Technology on the Requirements of Rain Attenuation Modeling for Communication System
Specification and Analysis at the Ka-Band and Beyond
Research and Technology 1995; March 1996; 1 pp.; In English; No Copyright; Avail: Other Sources; Abstract Only
With the advent of the use of the Ka-band for space communications, coupled with the introduction of digital modulation
techniques as well as multiple-beam methodology for satellites, the NASA Lewis Research Center has deemed it necessary
to reassess the plethora of rain attenuation prediction models in use (computer models that predict the attenuation of signals
by rain). The Advanced Communication Technology Satellite (ACTS) project, undertaken by NASA in 1983, offered such
challenges to rain attenuation prediction modeling. An examination of the work done in this area shows that, up to 1983, no
such single modeling formalism existed that could fulfill the requirements of theACTS specifications. Not even the work done
by the NASA Propagation Experimenters Group had envisioned such requirements, so no dynamic Ka-band data existed from
which one could draw conclusions. In response to this need, Lewis developed the ACTS Rain Attenuation Prediction Model.
A detailed discussion of the derivation of the model’s basic relations can be found in reference 1. The model as well as its
software implementation won the Space Act Award for 1992. In addition to the review of the model, a recommendation is
given in reference 2 for a new evaluation of the performance of satellite communication systems, in particular, for those to
be operating within the Ka-band and above. These systems will necessarily employ some type of dynamic rain-fade mitigation
procedure.
Author
ACTS; Rain; Attenuation; Mathematical Models; Extremely High Frequencies; Satellite Communication
20050172130 NASA Lewis Research Center, Cleveland, OH, USA
Highly Efficient Amplifier for Ka-Band Communications

Research and Technology 1995; March 1996; 2 pp.; In English; No Copyright; Avail: Other Sources; Abstract Only
An amplifier developed under a Small Business Innovation Research (SBIR) contract will have applications for both
satellite and terrestrial communications. This power amplifier uses an innovative series bias arrangement of active devices to
achieve over 40-percent efficiency at Ka-band frequencies with an output power of 0.66 W. The amplifier is fabricated on a
2.0- by 3.8-square millimeter chip through the use of Monolithic Microwave Integrated Circuit (MMIC) technology, and it
uses state-of-the-art, Pseudomorphic High-Electron-Mobility Transistor (PHEMT) devices. Although the performance of the
MMIC chip depends on these high-performance devices, the real innovations here are a unique series bias scheme, which
results in a high-voltage chip supply, and careful design of the on-chip planar output stage combiner. This design concept has
ramifications beyond the chip itself because it opens up the possibility of operation directly from a satellite power bus (usually
28 V) without a dc-dc converter. This will dramatically increase the overall system efficiency. Conventional microwave power
67
amplifier designs utilize many devices all connected in parallel from the bias supply. This results in a low-bias voltage,
typically 5 V, and a high bias current. With this configuration, substantial I(sup 2) R losses (current squared times resistance)
may arise in the system bias-distribution network. By placing the devices in a series bias configuration, the total current is
reduced, leading to reduced distribution losses. Careful design of the on-chip planar output stage power combiner is also
important in minimizing losses. Using these concepts, a two-stage amplifier was designed for operation at 33 GHz and
fabricated in a standard MMIC foundry process with 0.20-m PHEMT devices. Using a 20-V bias supply, the amplifier
achieved efficiencies of over 40 percent with an output power of 0.66 W and a 16-dB gain over a 2-GHz bandwidth centered
at 33 GHz. With a 28-V bias, a power level of 1.1 W was achieved with a 12-dB gain and a 36-percent efficiency. This
represents the best reported combination of power and efficiency at this frequency. In addition to delivering excellent power
and gain, this Ka-band MMIC power amplifier has an efficiency that is 10 percent greater than existing designs. The unique
design offers an excellent match for spacecraft applications since the amplifier supply voltage is closely matched to the typical
value of spacecraft bus voltage. These amplifiers may be used alone in applications of 1 W or less, or several may be combined
or used in an array to produce moderate power, Ka-band transmitters with minimal power combining and less thermal stress
owing to the combination of excellent efficiency and power output. The higher voltage operation of this design may also save
mass and power because the dc-dc power converter is replaced with a simpler voltage regulator.
Author
Amplifier Design; Extremely High Frequencies; Power Amplifiers; Satellite Communication; Fabrication
20050173173 Naval Postgraduate School, Monterey, CA USA
Collaborative Applications Used in a Wireless Environment at Sea for Use in Coast Guard Law Enforcement and

Homeland Security Missions
Klopson, Jadon E.; Burdian, Stephen V.; Mar. 2005; 109 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432285; No Copyright; Avail: Defense Technical Information Center (DTIC)
This thesis analyzes the potential impact of incorporating wireless technologies, specifically an 802.11 mesh layer
architecture and 802.16 Orthogonal Frequency Division Multiplexing, in order to effectively and more efficiently transmit data
and create a symbiotic operational picture between Coast Guard Cutters, their boarding teams, Coast Guard Operation Centers,
and various external agencies. Two distinct collaborative software programs, Groove Virtual Office and the Naval Postgraduate
School’s Situational Awareness Agent, are utilized over the Tactical Mesh and OFDM network configurations to improve the
Common Operating Picture of involved units within a marine environment to evaluate their potential impact for the Coast
Guard. This is being done to increase the effectiveness and efficiency of Coast Guard units while they carry out their Law
Enforcement and Homeland Security Missions. Through multiple field experiments, including Tactical Network Topology and
nuclear component sensing with Lawrence Livermore National Laboratory, we utilize commercial off the shelf (COTS)
equipment and software to evaluate their impact on these missions.
DTIC
Coasts; Frequency Division Multiplexing; Interoperability; Law (Jurisprudence); Seas; Security; Wireless Communication
20050173186 Naval Postgraduate School, Monterey, CA USA
Performance Evaluation of a Prototyped Wireless Ground Sensor Network
Tingle, Mark E.; Mar. 2005; 112 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432328; No Copyright; Avail: Defense Technical Information Center (DTIC)
This thesis investigated the suitability of wireless, unattended ground sensor networks for military applications. The
unattended aspect requires the network to self-organize and adapt to dynamic changes. A wireless, unattended ground sensor
network was prototyped using commercial off-the-shelf technology and three to four networked nodes. Device and network
performance were measured under indoor and outdoor scenarios. The measured communication range of a node varied
between three and nineteen meters depending on the scenario. The sensors evaluated were an acoustic sensor, a magnetic
sensor, and an acceleration sensor. The measured sensing range varied by the type of sensor. Node discovery durations
observed were between forty seconds and over five minutes. Node density calculations indicated that the prototype was
scalable to five hundred nodes. This thesis substantiated the feasibility of interconnecting, self-organizing sensor nodes in
military applications. Tests and evaluations demonstrated that the network was capable of dynamic adaptation to failure and
degradation.
DTIC

Communication Networks; Evaluation; Performance Tests; Telecommunication
68
20050173193 Naval Postgraduate School, Monterey, CA USA
Command and Control of Special Operations Forces Missions in the US northern Command Area of Responsibility
McGregor, Ottis W., III; Mar. 2005; 111 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432342; No Copyright; Avail: Defense Technical Information Center (DTIC)
The need for a well thought out, planned, and rehearsed command and control organization to conduct special operations
in the US Northern Command Area of Responsibility is vital to success in defending the Homeland. Currently,
USNORTHCOM does not have an apportioned or assigned command and control structure for the conduct of special
operations. This thesis analyzes three courses of action to fulfill this requirement: use the current USNORTHCOM battle staff
command structure including the integration of the Standing Joint Force Headquarters-North; rely on the newly formed US
Special Operations Command’s Joint Task Force Structures; and establish a Theater Special Operations Command North
assigned to USNORTHCOM. Through the conduct of analysis and research this thesis recommends that The Joint Staff direct
the reorganization required to establish a Theater Special Operations Command North to exercise command and control of
special operations forces conducting operations in the USNORTHCOM AOR.
DTIC
Command and Control; Military Personnel
20050173196 Defense Science Board, Washington, DC USA
Report of the Defense Science Board 1996 Task Force on Command, Control, Communications, Intelligence,
Surveillance and Reconnaissance (C4ISR) integration
Herman, Robert; Welch, Larry; Feb. 1997; 25 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432361; No Copyright; Avail: Defense Technical Information Center (DTIC)
The Deputy Secretary of Defense, in an effort to accelerate the development of Command, Control, Communications,
Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) integration and architecture efforts in the Department of
Defense, directed that a DoD-wide Integration Task Force (ITF) be created. He designated Assistant Secretary of Defense
(C3I) to sponsor, organize and manage this effort. The Defense Science Board (DSB) was requested then to establish a Task
Force on C4ISR Integration to assist this internal DoD process by providing: * Advice to the ITF chairman on all aspects of
C4ISR integration. * Separate reports of its judgments on these matters to the Department The Terms of Reference for this
Task Force are attached as Appendix A and the list of members as Appendix B. The DSB Task Force met four times with the
leaders of the ITF. During each meeting, the ITF leaders described the process, organization and results of the ITF efforts to

date. Based on these interactions, the DSB task Force formulated a set of inputs for consideration by the ITF. Two letter reports
were submitted by the DSB Task Force during the course of its deliberations.
DTIC
Command and Control; Intelligence; Reconnaissance; Surveillance; Telecommunication
20050173212 Naval Postgraduate School, Monterey, CA USA
Building a Simulation Toolkit for Wireless Mesh Clusters and Evaluating the Suitability of Different Families of Ad
Hoc Protocols for the Tactical Network Topology
Karapetsas, Konstantinos; Mar. 2005; 99 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432399; No Copyright; Avail: Defense Technical Information Center (DTIC)
Wireless mesh networking has emerged as the successor of the traditional ad hoc networks. New technological advances,
the standardization of protocols and interfaces and the maturity of key components have made it possible for current mesh
research groups to set goals that are really close to the world’s expectations. The objective of this research is to design and
implement a simulation toolkit for wireless mesh clusters that can be used as an additional performance evaluation technique
for the Tactical Network Topology program of Naval Postgraduate School. This toolkit is implemented in the OPNET
simulation environment and it incorporates various nodes running different ad hoc routing protocols. Furthermore, the
investigation of a suitable combination of protocols for the Tactical Network Topology is achieved by creating scenarios and
running a number of simulations using the mesh toolkit.
DTIC
Environments; Kits; Protocol (Computers); Simulation; Topology
20050173224 Naval Postgraduate School, Monterey, CA USA
An Analysis of Network and Sensor Performance Within IEEE 802.X Wireless MESH Networks in the Tactical
Network Topology (TNT)
Davis, Joseph A., Sr; Mar. 2005; 69 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432417; No Copyright; Avail: Defense Technical Information Center (DTIC)
69
The objective of this research is to analyze the network performance and sensor functionality, efficacy and usability of
IEEE 802.x wireless MESH networks within a DoD Tactical network environment. Multiple sensor configurations operating
with wireless MESH network technologies will be researched and analyzed for performance in expeditionary environment
situations. Specifically, this thesis will attempt establish the foundation for the development of wireless MESH ‘network
health’ models by examining the performance of sensors operating within a MESH network and define which network

performance metrics equate to good quality of service. This research will experiment with different application, sensor, and
network configurations of currently available COTS components; such as, voice, video and data hardware. This thesis will lay
the groundwork for wireless network MESH predictability, which will enable the optimal use of sensors within a tactical
network environment.
DTIC
Communication Networks; Topology
20050173254 Army War Coll., Carlisle Barracks, PA USA
Italian Army and Society: From ‘Separation’ to a relationship of Trust Towards Men in Uniform, Strategic Value of
Communication
Miglietta, Guglielmo L.; Mar. 2005; 41 pp.; In English
Report No.(s): AD-A432491; No Copyright; Avail: Defense Technical Information Center (DTIC)
The relations between the Italian public and the Army were difficult and characterized by mutual distrust until the end of
the 1980s. In the 1990s, very few would have bet on the efficiency of the Italian Army in the new peace missions, but the
decision to send troops outside the national borders has improved the image of the Institution. Today it is perceived useful,
gaining the attention of the mass media. The Italian Army has succeeded in deleting the negative image when compared to
other more organized and efficient armies. Today, in fact, it has the image of a modern armed force, professionally well
prepared, efficient and reflective of the best values of the nation. The journey that led our Army to enjoy the widest
appreciation for its work was favored by the non intrusive approach of our soldiers and by their capability of positive
interaction with the local populations. In this sense, the empathetic characteristic of the Italian spirit emerged on all occasions.
The Italian servicemen revealed very special talents and characteristics, including the capability of socializing, of entering into
relations with others, of integrating within the operations without being ‘cumbersome’. On the contrary, they were a precious
support in the little and great difficulties suffered by people emerging from conflict or humanitarian disaster. This new image
is also the outcome of fundamental changes in the way the institution approaches public affairs.
DTIC
Human Beings; International Relations; Males; Military Operations
20050173255 Army War Coll., Carlisle Barracks, PA USA
Defeating Anti-Americanism
McKenzie, Mark T.; Mar. 2005; 23 pp.; In English
Report No.(s): AD-A432495; No Copyright; Avail: Defense Technical Information Center (DTIC)
The USA of America has enjoyed unrivaled success militarily and economically over the past two decades. This success

comes at a cost for Americans as growing international criticisms of U.S. policy and anti-Americanism increases dramatically
from other countries around the globe. In addition to this criticism during this time of unrivaled power, America has seen a
drastic increase in attacks against its citizens in foreign countries, such as the Marine barracks bombing in Beirut, the Khobar
tower attack, and the attack on the USS Cole. While terrorist attacks within the U.S. have been limited in nature comparatively,
the attacks of September 11, 2001, have reawakened U.S. citizens to the inherent dangers of today s global environment, and
the effects of anti-Americanism. Current U.S. policy is best stated by President Bush in the 2002 National Security Strategy:
Freedom is the non-negotiable demand of human dignity, the birthright of every person-in every civilization. Does this policy
of globalization increase or decrease anti- American sentiments at home and abroad? This research paper will study the history
of anti- Americanism, its causes, and current policies, and offer recommendations to defeat anti-Americanism and limit its
adverse effects.
DTIC
Policies; Security
20050173259 Army War Coll., Carlisle Barracks, PA USA
Strategic Communications for the War on Terrorism, Countering Middle Eastern Anti-American Bias
Gallagher, Paul; Mar. 2005; 24 pp.; In English
Report No.(s): AD-A432507; No Copyright; Avail: Defense Technical Information Center (DTIC)
70
Despite the growth of media outlets in the Middle East inarguably the understanding of US strategic vision and intent is
commonly misunderstood and/or misconstrued. In fact an active mis-information campaign is commonly practiced by media
throughout the region. The loss to the US in ‘soft power’ and influence has been incalculable and must be reversed. My intent
in this document is to analyze the makeup of the average man on the Arab Street, utilize the information the analysis provides,
and devise a strategy to combat the propaganda and mis-information he has been exposed to throughout his life. Based on
those findings I will develop proposals that utilize all aspect of America’s national power to include initiatives in both the
public and private sectors.
DTIC
Bias; Middle East; Terrorism; Warfare
20050173319 Naval Postgraduate School, Monterey, CA USA
Optimizing Global Combat Logistics Force Support for Sea Base Operations
DeGrange, Walter C.; Mar. 2005; 70 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432623; No Copyright; Avail: Defense Technical Information Center (DTIC)

The Navy has to choose the number of, and designs for, ships in the Combat Logistics Force (CLF), and then plan how
to use them to provide logistical support to our Carrier Strike Groups, Expeditionary Strike Groups, and Seabasing platforms
engaged in any variety of worldwide conflicts. CLF ships are very expensive to build and equip and our budget is limited we
need to make sure the ships we buy and the way we integrate these with our CLF fleet can continue to provide the flexible
support our Navy requires. We introduce a decision support tool using a global sea route and resupply base model, and a daily
time resolution optimization of CLF ship activities to support any complete, worldwide scenario. Our result is an optimal,
face-valid daily operational logistics plan a schedule of evolutions for each available CLF ship. We discover exactly how to
use CLF ships to support a notional, but particularly relevant, preemptive combat scenario with follow-on humanitarian
assistance missions. Finally, we study how changing CLF ship numbers and missions can enhance operational effectiveness.
DTIC
Armed Forces (United States); Combat; Decision Support Systems; Logistics Management; Seas; Support Systems; System
Effectiveness
20050173337 Naval Postgraduate School, Monterey, CA USA
Performance Analysis of Management Techniques for SONET/SDH telecommunications Networks
Ng, Hwee P.; Mar. 2005; 77 pp.; In English; Original contains color illustrations
Report No.(s): AD-A432669; No Copyright; Avail: Defense Technical Information Center (DTIC)
The performance of network management tools for SONET/SDH networks subject to the load conditions is studied and
discussed in this thesis. Specifically, a SONET network which consists of four CISCO ONS 15454s, managed by a CISCO
transport Manager, is set up in the Advanced Network Laboratory of the Naval Postgraduate School. To simulate a realistic
data transfer environment for the analysis, Smartbits Avalanche software is deployed to simulate multiple client-server
scenarios in the SONET network. Traffic from the management channel is then captured using a packet sniffer. Queuing
analysis on the captured data is performed with particular emphasis on properties of self-similarity. In particular, the Hurst
parameter which determines the captured traffic’s degree of self-similarity is estimated using the Variance-Index plot
technique. Link utilization is also derived from the computation of first-order statistics of the captured traffic distribution. The
study shows that less management data was exchanged when the SONET network was fully loaded. In addition, it is
recommended that CTM 4.6 be used to manage not more than 1552 NEs for safe operation. The results presented in this thesis
will aid network planners to optimize the management of their SONET/SDH networks.
DTIC
Communication Networks; Management Information Systems; Management Methods; Reliability Analysis;
Telecommunication

20050173348 Army Research Lab., Adelphi, MD USA
Intentional Jamming Suppression in a Frequency-Domain Ultra-Wideband Multicarrier Communication Receiver
Hoyos, Sebastian; Sadler, Brian M.; Arce, Gonzalo R.; Dec. 2004; 6 pp.; In English; Original contains color illustrations
Contract(s)/Grant(s): DAAD19-01-2-0011
Report No.(s): AD-A432691; No Copyright; Avail: Defense Technical Information Center (DTIC)
This paper presents suppression of intentional jamming in an ultra-wideband multicarrier communication receiver based
on analog to digital conversion (ADC) in the frequency domain. The samples of the spectrum of the received signal are used
71
in the digital receiver to estimate the transmitted symbols through a matched filter operation in the discrete frequency domain.
The proposed receiver is aimed at the reception of high information rates in a multicarrier signal with very large bandwidth.
Thus, the receiver architecture provides a solution to some of the challenging problems found in the implementation of
conventional wideband multicarrier receivers based on time-domain ADC, and it is directly applicable to multicarrier
ultra-wideband communication receivers. Additional advantages of the proposed receiver include the possibility of optimally
allocating the available number of bits for the A/D conversion across the frequency domain samples, narrowband interference
suppression based on the MMSE solution that can be directly carried out in the frequency domain, and inherent robustness
to frequency offset which makes it an attractive solution when compared with traditional multicarrier receivers.
DTIC
Analog to Digital Converters; Broadband; Frequencies; Jamming; Receivers; Wideband Communication
20050173355 Office of the Project Manager Night Vision/Reconnaissance Surveillance and Target Acquisition, Fort Belvoir,
VA USA
Sensor Data Link - Flexible and Standard Digital Communications for Current and Future Force Sensors
Whitworth, Robin; Mayott, Gregory; Meehan, James R.; McKerley, Sally S.; Patty, Kira D.; Dec. 2004; 3 pp.; In English
Report No.(s): AD-A432700; No Copyright; Avail: Defense Technical Information Center (DTIC)
To fulfill evolving sensor system interface and communications requirements, a team of government organizations have
collaborated to develop the Sensor Data Link (SDL); providing a flexible framework of joint standard data representations,
messages, and common processes for current and Future Force sensors.
DTIC
Communication Networks; Data Links; Multisensor Fusion; Protocol (Computers); Pulse Communication; Standardization
33
ELECTRONICS AND ELECTRICAL ENGINEERING

Includes development, performance, and maintainability of electrical/electronic devices and components; related test equipment; and
microelectronics and integrated circuitry. for related information see also 60 Computer Operations and Hardware; and 76 Solid-State
Physics. For communications equipment and devices see 32 Communications and Radar.
20050169565 Institute of Electrical and Electronics Engineers, Piscataway, NJ, USA
IEEE Antennas and Propagation Society International Symposium, Volume 1
[1999]; 721 pp.; In English; Held in Conjunction with USNC/URSI National Radio Science Meeting at the University of
Central Florida, 11-16 July 1999, Orlando, FL, USA; See also 20050169566 - 20050169737
Report No.(s): IEEE-Catalog-99CH37010-Vol-1; LC-90-640397; Copyright; Avail: Other Sources
The following topics were discussed: Dielectric and Wire Antennas for Wireless Communications; Scattering from
Natural Targets and Magnetized Plasma; EM Education; Broadband and Multifrequency Antennas; Phased Arrays; Advances
in FDTD; Microstrip Circuits; Circularly Polarized Microstrip Patch Antennas; Waveguide and Transmission Line Analysis;
Applications of Wavelets; Optimization Methods in EM Design; and Development and Applications of FEM.
Derived from text
Antennas; Broadband; Wireless Communication; Patch Antennas; Transmission Lines; Wavelet Analysis; Finite Difference
Time Domain Method; Microstrip Antennas
20050169570 Florida Atlantic Univ., Boca Raton, FL, USA
The Effects of Substrate Permittivity and Pulse-Width on the Crosstalk as Applied to Ultra-High-Speed Microstrip
Lines
Ungvichian, Vichate; Malisuwan, Settapong; IEEE Antennas and Propagation Society International Symposium, Volume 1;
[1999], pp. 202-205; In English; See also 20050169565; Copyright; Avail: Other Sources
The study emphasizes on the effects of the frequency-dependent dielectric loss of substrate along the lines and with
different Gaussian pulse waveforms. The Gaussian pulses are used in the simulations due to the broadband characteristic,
which may have the frequency components in the GHz range. This pulse signal is fed to one of the microstrip lines at one
end and with match termination on the other (called signal line) and the second line (sense line) is terminated at both ends
72
by the match loads. The simulations encompass several combinations of t (5, 10, 20, 30, 40, and 50 ps), E(sub t)less than 20,
and line-length between 10 to 100 mm.
Derived from text
Microstrip Transmission Lines; High Speed; Dielectric Loss; Crosstalk; Permittivity; Substrates
20050169571 Texas A&M Univ., College Station, TX, USA

A Wide-Band Uniplanar Mixer
Hsu, Pang-Cheng; Nguyen, Cam; Kintis, Mark; IEEE Antennas and Propagation Society International Symposium, Volume
1; [1999], pp. 214-217; In English; See also 20050169565; Copyright; Avail: Other Sources
We report the development of awideband uniplanar singly balanced diode mixer using coplanar waveguide and slot line.
The first-design mixer has a measured conversion loss from 6 to I0 dB for the RF signal from 7.1 to 10.13Hz and the LO signal
of 3.5 dBm at 7 GHz. The LO-RF isolation is better than 20 dB, and the isolations from the IF to the LO and RF ports are
more than 36 dB. This mixer circuit is simple and has a wide bandwidth and goodinterport isolations. Futhermore, its uniplanar
nature allows solid-state devices to be mounted easily and no via-holes are needed for ground connections. These features are
attractive for low-cost microwave and millimeter-wave integrated circuits.
Author
Bandwidth; Fabrication; Diodes; Mixers
20050169573 Universidade Federal do Para, Brazil
Characterization of an Optically-Controlled Double-Channel Lossy-Dielectric Waveguide
LeonidasdaSilvaSouzaSobrinho, Carlos; Giarola, Attilio Jose; IEEE Antennas and Propagation Society International
Symposium, Volume 1; [1999], pp. 306-309; In English; See also 20050169565; Copyright; Avail: Other Sources
A double-channel lossy-dielectric waveguide, having its propagation characteristics controlled by the action of light, is
analyzed here. The light is incident on a semiconductor material that constitutes the inner channel of the waveguide structure,
generating a plasma. The analysis of the problem is done by using the finite difference in the frequency domain (FDFD)
method which was found to be efficient for this analysis. The results presented here were confirmed with those obtained using
the finite element method.
Author
Finite Difference Theory; Finite Element Method; Frequency Domain Analysis; Semiconductors (Materials); Dielectric
Waveguides
20050169574 Lafayette Coll., Easton, PA, USA
Wavelet Beamspace STAP For Uniform Linear Arrays
Jouny, I.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 348-351; In English; See
also 20050169565; Copyright; Avail: Other Sources
Space time adaptive processing is implemented in this paper in beamspace using a wavelet based transformation. We show
that given a fixed number of beamspace elements, wavelet based STAP outperforms that of DFT based, or sinusoidal tapers
based STAP. Wavelet based decomposition divides the uniformly sampled element-space array into nonuniform dyadically

distributed orthogonal beam-space elements. Adaptive processing in the wavelet domain improves signal-to-interference plus
noise ratio depending on the type of wavelet used.
Derived from text
Wavelet Analysis; Linear Arrays; Space-Time Adaptive Processing; Beam Interactions
20050169577 Dumlupinar Univ., Kutahya, Turkey
UTD-Based Propagation Model for the Path Loss Characteristics of Cellular Mobile Communications System
Kara, Ali; Yazgan, Erdem; IEEEAntennas and Propagation Society International Symposium, Volume 1; [1999], pp. 392-395;
In English; See also 20050169565; Copyright; Avail: Other Sources
This work presents a UTD-based path loss model for cellular mobile communications system in urban environment. The
model considers multiple building diffraction occurring in cellular environments outside the high-rise urban core. Using UTD
wedge diffraction model, the roofs of the successive building blocks are simulated by finitely conducting wedges so that
material properties of the buildings are included.
Author
Mobile Communication Systems; Diffraction; Losses
73
20050169578 EMAG Technologies, Inc., Ann Arbor, MI, USA
An Accelerated Hybrid Genetic Algorithm for Optimization of Electromagnetic Structures
Jones, Dennis P.; Sabet, Kazem F.; Cheng, Jui-Ching; Katehi, Linda P. B.; Sarabandi, Kamal; Harvey, James F.; IEEE
Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 426-429; In English; See also
20050169565; Copyright; Avail: Other Sources
This paper presents a novel optimization technique that combines classical and statistical methods in an innovative and
efficient way. In specific, an evolutionary genetic algorithm (GA) has been developed that utilizes a local minimization scheme
based on the method of conjugate directions. The proposed optimizer has been applied to the design of planar microwave
circuits and printed antenna arrays. The advantages of the proposed technique are illustrated by ample numerical results.
Author
Genetic Algorithms; Physical Optics; Electromagnetism
20050169580 Eidgenoessische Technische Hochschule, Lausanne, Switzerland
PCS Antenna Design: The Challenge of Miniaturisation
Staub, Olivier; Zuercher, Jean-Francois; Skrivervik, Anja K.; Mosig, Juan R.; IEEE Antennas and Propagation Society
International Symposium, Volume 1; [1999], pp. 548-551; In English; See also 20050169565; Copyright; Avail: Other

Sources
As mobile communication equipments become smaller and lighter, antennas must follow the trend. However, antenna size
reduction is done at the expense of gain and bandwidth. This follows from the fact that an antenna is used to transform a free
wave into a radiated wave. One understands easily that an antenna can perform this transformation only with a poor efficiency
when its size is much smaller than the wavelength. If the loss of gain ca_ be, to some extent, compensated by amplification,
this is obviously not the case for the bandwidth.
Derived from text
Amplification; Bandwidth; Antenna Design; Communication Equipment
20050169585 Deltec New Zealand Ltd., New Zealand
Adjustable Multifilar Helical Antenna with Reduced Frequency Scanning
duToit, C. F.; Chadwick, P. E.; Butland, R. J.; Vaughan, R. G.; IEEE Antennas and Propagation Society International
Symposium, Volume 1; [1999], pp. 18-21; In English; See also 20050169565; Copyright; Avail: Other Sources
An adjustable ‘scanning mode’ multifilar helical antenna with reduced frequency scanning is described. The antenna was
designed for the Australian Mobile Satellite System. operating at about 1.6GHz. The design described here features a
centre-fed arrangement, which is shown to substantially reduce frequency scanning in this type of antenna.A novel mechanical
adjustment technique is also described, which allows the main beam of the antenna to be tilted.
Author
Adjusting; Frequency Scanning; Helical Antennas
20050169587 Georgian Technical Univ., Tbilisi, Georgia
Statistical Characteristics of Multiple Scattered Electromagnetic Waves in Layer of Magnetized Turbulent Plasma
Jandieri, G. V.; Pirtskhlaishvili, N. G.; Gavrilenko, V. G.; Semerikov, A. A.; IEEE Antennas and Propagation Society
International Symposium, Volume 1; [1999], pp. 60-63; In English; See also 20050169565; Copyright; Avail: Other Sources
Over the last years it was established that the absorption of electromagnetic waves in a turbulent plasma caused by
particles collision leads as to the decrease of their amplitudes, as well as to the substantial distortion of an angular distribution
of the scattered field. Particularly strongly it showed itself at waves propagation at great angle with respect to the external
magnetic field. [1].The influence of the distance between located emitter and the boundary of a plane layer of the turbulent
plasma, as well as the distance between an another boundary of plasma layer and the receiver on statistical characteristics of
a multiple scattered radiation is analysed.
Derived from text
Electromagnetic Radiation; Magnetic Fields; Plasma Layers; Angular Distribution; Turbulence; Boundary Layers

20050169589 Arizona Univ., Tucson, AZ, USA
Characterization and Design Methodology for the Dual Exponentially Tapered Slot Antenna
Greenberg, Marc C.; Virga, Kathleen; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 88-91; In English; See also 20050169565; Copyright; Avail: Other Sources
74
Tapered slot antennas are simple planar structures with broadband characteristics that are typically used in arrays for radar
applications, mobile satellite communications, and phased arrays. Many groups have studied tapered slot antennas using
approaches that are either dominantly theoretical in nature or approaches that are more experimental in nature. Most published
work has been limited to the linearly tapered slot and Vivaldi antennas. Very little has been published on the dual exponentially
tapered slot antenna (DETSA), originally referred to as a wide band bunny-ear element [1]. Presented here is a performance
characterization for the DETSA. It has been found that careful design of the DETSA can give improved directivity and half
power beamwidth (HPBW) performance over the Vivaldi. Also presented is a method for def’ming the DETSA dimensions
in terms of ratios so design features of different DETSAs can be quantified and their performance compared.
Derived from text
Beams (Radiation); Slot Antennas; Planar Structures; Phased Arrays; Characterization; Broadband
20050169591 Massachusetts Univ., Amherst, MA, USA
Effects of Slotline Cavity on Dual-Polarized Tapered Slot Antenna Arrays
Chio, Tanhuat; Schaubert, Daniel H.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 130-133; In English; See also 20050169565; Copyright; Avail: Other Sources
Tapered Slot Antenna (TSA) was introduced by Lewis et al [1] in 1974. Its potential of being wideband and widescan
makes it a prime candidate for high performance phased arrays. Parameter studies performed on single-polarized TSA arrays
[2], [3] indicate that such a high performance array may be possible. More recently,Wunsch [4] presented a full-wave Moment
Method (MoM) analysis program that is capable of analyzing dual-polarized infinite TSA arrays. The code has been extended
here to include frequency interpolation [5] of the impedance matrix to reduce computation lime to an acceptable level so that
a parameter study of dual-polarized TSA arrays can be performed. In this paper, the effects of the slotline cavity portion of
the element is shown to have a significant impact on the low frequency performance of a dual-polarized TSA array and to
affect also the mid-band and high frequency performance.
Derived from text
Antenna Arrays; Method of Moments; Impedance; High Frequencies; Slot Antennas; Phased Arrays; Broadband
20050169593 Lockheed Martin Missiles and Space, Sunnyvale, CA, USA

Relative Accuracy of Several Low-Dispersion Finite-Difference Time-Domain Schemes
Shlager, Kurt L.; Schneider, John B.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 168-171; In English; See also 20050169565; Copyright; Avail: Other Sources
For electrically large problems, the numerical dispersion inherent in the classical Yee finite-difference time-domain
(FDTD) algorithm can introduce significant errors. Over the past ten years there have been several FDTD schemes published
with the goal of reducing dispersion errors. In this paper, a comparison of the 2-D dispersion error of several of these
low-dispersion schemes is made. The accuracy of each FDTD scheme is compared via direct evaluation of the dispersion
relation governing the algorithm. (In addition, numerical experiments were performed to verify the derived dispersion
relations.) The algorithms compared include Krumpholz and Katehi’s MRTD scheme, Hadi and Piket-May’s M24 scheme,
Cole’s Non-Standard scheme, Forgy isotropic scheme, Nehrbass, Jetvic and Lee’s (NJL) reduced dispersion scheme, and
Turkel’s Ty implicit scheme. The dispersion characteristics are typically derived by assuming a time harmonic plane-wave
solution in an isotropic, homogeneous, linear, and lossless medium. The FDTD dispersion relation can be expressed in terms
of the dispersion error per wavelength (lambda). This error is a function of the angle of propagation, the number of cells per
wavelength, and the Courant number, which is given bys=cDelta t/delta. Because of space limitations, neither the FDTD
algorithms nor their dispersion relations are presented here; instead, some ‘typical’ dispersion results are presented. All results
are obtained assuming a uniform grid with spatial increments Delta z = Delta y = delta. Each scheme is evaluated at the
Courant number which minimizes the dispersion for that algorithm at a resolution of 10 cells/lambda.
Author
Finite Difference Time Domain Method; Accuracy; Wave Dispersion; Wavelengths; Errors
20050169596 Nevada Univ., Reno, NV, USA
Simplified Analysis of a Three Line Microstrip Coupler on Anisotropic Substrate
Rawat, Banmati S.; Boiteau, V.; Chi, J.; LeBihan, Jean; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 222-225; In English; See also 20050169565; Copyright; Avail: Other Sources
A three line microstrip coupler on anisotropic substrate has been analyzed by using empirical and semi-numerical
relations for obtaining strip-, gap and fringe-capacitances of the system. From these capacitances the coupler mode
75
impedances, phase velocities and velocity equalization for various W/h and S/h values have been obtained. The results are
within 5% of the ones obtained from vigorous numerical techniques.
Author
Microstrip Devices; Anisotropic Media; Substrates; Couplers

20050169600 Musashi Inst. of Tech., Tokyo, Japan
A Study on Reflection Eoefficient from Double Layered Lossy Dielectric by using Flanged Rectangular Waveguide
Hirano, Makoto; Takahashi, Masaharu; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 298-301; In English; See also 20050169565; Copyright; Avail: Other Sources
Knowing the permittivity and permeability of materials is often needed when we design radar absorbers or radomes.
Although resonator method and waveguide method are widely used for microwave measurement[1],they require to cut sample
for fitting inner walls, take a lot of labor and it is difficult to have accurate measurements especially on higher frequencies
because of occurrence of errors by the cause of gap between the wall and the sample. On the other hand, effective method
of nondestructive measurement to determine the complex permittivity of dielectrics from the reflected wave by contacting the
flanged rectangular waveguide to dielectric sheet have been investigated in recent years[2][3][4]. In these investigations, the
exact solution of reflection coefficient has been obtained by means of the spectral domain analysis, and gives good agreement
with experimental results[4].
Derived from text
Permittivity; Permeability; Radomes; Radar Absorbers; Rectangular Waveguides; Reflectance; Reflected Waves; Waveguides;
Dielectrics
20050169601 Hong Kong Univ., Hong Kong
Three Dimension Edge FEM Analysis of Inhomogeneous Chiral Medium Loaded Waveguide Discontinuity
Chen, R. S.; Yung, Edward K. N.; Xie, Z. M.; Han, Y. F.; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 310-313; In English; See also 20050169565; Copyright; Avail: Other Sources
Dielectric-filled waveguides have important applications in many microwave devices, e.g., isolators and phase shiners. In
these devices, there are always discontinuity for the constituent dielectrics in both shape and materials.Among them, the chiral
medium is particularly receiving much interest because the chirality admittance provides one additional parameter that could
make the practical designs more flexible. Traditionally, most of the investigations are based on the mode or field matching
method with a particular class of geon_etries. Recently three-dimensional discontinuities in chiro-waveguides was first
analysed in [1]. However, it has been recognized that for a method to be useful as a good design tool, it must be capable of
efficiently handling three-dimensional discontinuities with general configurations. Among the available techniques, the
finite-element method (FEM) has been considered to be simplest in formulation and most flexible in modelling arbitrary
shaped, inhomogeneously dielectric-filled discontinuity.
Derived from text
Dielectric Waveguides; Electrical Impedance; Finite Element Method; Microwave Equipment; Chirality

20050169602 Ho Chi Minh City Univ., Ho Chi Minh, Viet Nam
Modes in Metallic Waveguides of Elliptic Sector
Do-Nhat, Tam; Alhargan, Fayez A.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 318-321; In English; See also 20050169565; Copyright; Avail: Other Sources
The theoretical methods of analysing the modes of waveguides of metallic wails were established and described in details
in Marcuvitz’s handbook of waveguides [1]. However, the analysis of waveguides of sector with finite extended angle has not
been received much attention. Alhargan and Judah [2] have recently analysed circular and annular sectors. Such shapes are
required in the applications of power dividers and combiners. In this paper we shall investigate the modes of metallic
waveguides of elliptic sector. Such analysis requires the formulation and computation of Mathieu wave functions ([3],[4]) of
real order, that satisfy either the Dirichlet or the Neumann boundary conditions.
Derived from text
Waveguides; Modes; Wave Functions; Shapes
20050169608 Santander Univ., Cantabria, Santander, Spain
A New Method to Estimate Efficiently the Local Fading Statistics from Ray-Tracing
Torres, R. P.; Loredo, S.; Domingo, M.; Valle, L.; IEEE Antennas and Propagation Society International Symposium, Volume
1; [1999], pp. 412-415; In English; See also 20050169565
Contract(s)/Grant(s): CiCyT-TIC97-1129-C04-01; Copyright; Avail: Other Sources
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The application of the ray-tracing technique to site-specific radio propagation models has been widely used recently. This
technique can provide relatively fast and accurate prediction of pico and microcell radio coverage and channel impulse
response. However, some other parameters such as fast fading statistics can be of great interest when designing a mobile radio
system. Here we present a new method, which uses a ray-tracing technique [1] to obtain the fast fading statistics starting from
the Doppler power spectral density. The method appears to be more efficient and accurate that the methods used up till now.
Author
Fading; Ray Tracing; Radio Frequencies; Radio Transmission
20050169610 California Univ., Los Angeles, CA, USA
RCS Reduction in Planar, Cylindrical, and Spherical Structures by Composite Coatings using Genetic Algorithms
Mosallaei, H.; Rahmat-Samii, Y.; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 438-441; In English; See also 20050169565; Copyright; Avail: Other Sources
Radar cross section (RCS) reduction of a target using multilayered radar absorbing materials (RAM) has been an

important consideration in radar systems. The properties of the RAM depend on the frequency and for wide-band absorption,
a proper composite selection of these materials is necessary. This paper focuses on the design of a wide-band multilayered
RAM coating for planar, cylindrical, and spherical conducting structures such that the RCS is reduced considerably. The
method is based on the Genetic Algorithm (GA) optimization technique integrated with the modal solution of Maxwell’s
equations in a multilayered geometry. It is shown that by a proper design of materials and their thickness, the RCS is reduced
significantly in a wide frequency bandwidth. Additionally, it is observed that the application of optimized coating for planar
structure can reduce the RCS of a cylindrical or spherical structure efficiently.
Derived from text
Coatings; Composite Materials; Cylindrical Bodies; Genetic Algorithms; Planar Structures; Radar Cross Sections
20050169611 Ericsson Microwave Systems A.B., Moelndal, Sweden
Simulated Annealing Optimization Applied to Antenna Arrays with Failed Elements
Redvik, Jonatan; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999], pp. 458-461; In
English; See also 20050169565; Copyright; Avail: Other Sources
Simulated annealing is applied to the synthesis of an array antenna when element failures occurs, by reoptimizing the
remaining elements amplitude and phase distribution. The goal is to reduce peak side lobe level whim constraining the gain
of the antenna.
Author
Simulated Annealing; Antenna Arrays; Sidelobes
20050169613 New Mexico State Univ., Las Cruces, NM, USA
Open-Region, Elecromagnetic Finite-Element Scattering Calculations in Anisotropic Media on Parallel Computers
Hennigan, Gary; Castillo, Steven; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 484-487; In English; See also 20050169565; Copyright; Avail: Other Sources
Open-region scattering calculations for complex, electrically large scatterers remains a difficult modeling and simulation
problem. The finite-element method (FEM) has been shown to be a viable approach to solving such problems. However,
conventional methods on serial computers limit the size which can be tackled with the FEM. In this paper, we demonstrate
the use of both a PML boundary condition along with a parallel solver for tackling large, complex problems containing
scatterers which are inhomogeneous and anisotropic.
Derived from text
Anisotropic Media; Finite Element Method; Parallel Computers; Mathematical Models; Scattering; Electromagnetism
20050169614 Universidad Politecnica de Valencia, Valencia, Spain

Prediction of Radiated Perturbations from Currents Inside Slotted Screens Using a Hybrid FEM Procedure
Nuno, L.; Balbastre, Juan V.; deosReyes, E.; IEEE Antennas and Propagation Society International Symposium, Volume 1;
[1999], pp. 500-503; In English; See also 20050169565; Copyright; Avail: Other Sources
Electronic systems use electric currents in its normal work, but these currents will also be the orion of radiated
perturbations that could affect the performance of neighbor systems. Thus, those circuits are enclosed in some kind of envelope
or shield, in order to reduce the amplitude of the perturbations produced by them. Nevertheless, the external envelopes must
sometimes be slotted, in order to connect the covered circuit to the exterior world (the expansion slots in PC’s are a very
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common example). Unfortunately, these slots will radiate some electromagnetic perturbations, but an accurate design can keep
them under critic values. As it will be shown below, traditional models based on aperture antennas can fail when some effects
(like edge effects) are not negligible, so a numerical approach is needed. The problem of slotted screens has been studied in
the past from the point of view of electromagnetic susceptibility (EMS) using different numerical techniques. The authors
presented a hybrid procedure based on the Finite Element Method (FEM) and the Modal Analysis that was successfully
applied to the study of EMS problems in slotted envelopes. In this work, that procedure has been adapted for solving the
electromagnetic interference (EMI) problem.
Derived from text
Electric Current; Finite Element Method; Perturbation; Slots
20050169617 Spike Technologies, Nashua, NH, USA
Omnidirectional Antennas for Wireless Communication
Herscovici, Naftali; Dziadek, Ed; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 556-559; In English; See also 20050169565; Copyright; Avail: Other Sources
The typical omnidirectional antenna used in the wireless communication industry is the grounded monopole. The
grounded monopoles as well as other similar wire antennas are simple, and relatively inexpensive to manufacture. Their
geometry though, is such that makes them protrusive and this is a real disadvantage in this industry, especially for indoor
applications. Furthermore, the omnidirectional coverage might not be optimal for many situations, where asymmetrical
patterns might be more appropriate. This paper proposes a number of non-protrusive antenna elements with an additional
benefit: beam shaping.
Derived from text
Antenna Components; Omnidirectional Antennas; Asymmetry; Monopoles
20050169619 Hosei Univ., Tokyo, Japan

A Circular Aperture Antenna Backed by a Cavity
Nakano, H.; Sugama, M.; Nakayama, K.; Yamauchi, J.; IEEE Antennas and Propagation Society International Symposium,
Volume 1; [1999], pp. 586-589; In English; See also 20050169565; Copyright; Avail: Other Sources
This paper presents a circular aperture antenna constructed using a triplate transmission line. The radiation characteristics
are evaluated using the FDTD method [1]. It is found that a circular cavity backing the aperture increases the radiation
efficiency.
Derived from text
Apertures; Dipole Antennas; Cavities; Finite Difference Time Domain Method; Transmission Lines
20050169620 Pennsylvania State Univ., University Park, PA, USA
Modeling of Periodic Structures Using the Finite Difference Time Domain (FDTD)
Yu, Wenhua; Dey, Supriyo; Mittra, Raj; IEEE Antennas and Propagation Society International Symposium, Volume 1; [1999],
pp. 594-597; In English; See also 20050169565; Copyright; Avail: Other Sources
Two-dimensional planar periodic structures find many applications in practice because of their spatial filtering
characteristics. A periodic array of conducting patch or aperture elements is often referred to as a frequency selective surface
(FSS), or a dichroic filter. Such arrays are frequently analyzed via the Method of Moments utilizing a periodic Green’s
function [1,2]. This method, however, is typically restricted to handling thin screens embedded in homogeneous dielectric
layers. For more complex elements, the Finite Difference Time Domain (FDTD) method [3] appears to be an effective tool
because of its ability to handle arbitrarily-shaped and inhomogeneous structures. For a normally-incident plane wave, it is
relatively simple to truncate the FDTD computational domain in the transverse planes by using simple periodic boundary
conditions [4-8]. However, the phase-shift or delay type of boundary conditions, that are required for the oblique incidence
case, are considerably more difficult to implement. We propose to obviate this difficulty by employing the FDTD in the context
of a waveguide simulator approach.
Derived from text
Periodic Functions; Finite Difference Time Domain Method; Planar Structures; Spatial Filtering; Green’s Functions;
Dielectrics
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