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midterm report research topic l pi t section impedance matching

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<b>HANOI UNIVERSITY OF SCIENCE AND TECHONOLOGY SCHOOL OF ELECTRICAL AND ELECTRONICS ENGINEERING </b>

<b>Midterm Report Analog Circuit 2 </b>

Research topic: L, Pi, T section impedance matching

<b>Student: Dương Đức Mạnh Student’s ID: 20193229 </b>

<b>Instructor: Dr Nguyen Nam Phong </b>

Hanoi, 03/2023

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Figure 2. L matching simulation (for the exercise) ... 9

Figure 3. Pi matching networks: (a) view of a Pi network; and (b) as two back- -back L networks with a tovirtual resistance, RV, between the networks. ... 10

Figure 4. Pi network (back- -back L-networks) provides higher Qto ... 10

Figure 5. Value Table (Pi network)... 12

Figure 6. ADS Schematic for 40 Ohm Center Impedance Design ... 12

Figure 7. Simulated Frequency Response of pi-networks for varying center Impedance ... 13

Figure 8. Increasing Zcenter beyond min {Rload,Rs} reduces the Q of match and at the same time compromises the maximum power that can be transferred at the design frequency ... 13

Figure 9. T network design approach. ... 14

Figure 10. Value Table (T network)... 15

Figure 11. ADS schematic for T matching network ... 16

Figure 12. T network simulation ... 16

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1. Introduction

1.1 Impedance Matching

• Impedance matching is important in electrical engineering because it allows for maximum power transfer between two points. In telephone systems, for example, minimizing echo on long-distance lines is achieved using match impedances. The telephone hybrid coil, where two wires are converted into four wires can also be achieved via matching.

• In audio amplifiers, impedances are not matched as it is typical for amplifiers to have output impedances that are lower than the load impedance for better speaker damping. But for higher-power amplifiers, such as those that use vacuum tubes, impedance-changing circuits are used to get a low output impedance in order to better match the amplifier's performance to the load impedance.

1.2 Matching Network (impedance transformer)

• A matching network, also called an impedance transformer, is used to create matched impedance between a source and a load (for example, between a power amplifier and an antenna).

• Lossless matching networks consist of reactive components only; resistive components are avoided because they would dissipate power, whereas the matching network is intended to facilitate the transfer of power from source to load.

• A straightforward, narrowband matching-network topology is the L network. It consists of two reactive components.

• Calculator tools can be used to quickly design a matching network based on the source impedance, load impedance, and signal frequency.

1.3 Research Requirements

Networks for Impedance Matching: T , Pi , T network • Circuit Configuration

• Frequency Response • Calculation of matching circuit • Simulation for result of matching circuit

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2. Overview, Design and Calculation, Simulation

<b>of Matching Networks (L, Pi, T) </b>

2.1 L matching network

<b>Overview </b>

The L-match impedance matching circuit is one of the circuits used to match the impedance between two points, usually a source and a load. The circuit got its name because the inductor and the capacitor form an L-shape . Note that the inductor and capacitor can be interchanged depending on the input. If you need to block direct current, then the capacitor is placed near the source. Otherwise, the inductor is placed near the source.

The load impedance can be transformed up or down using matching network. Simplest matching network is L-match. The value of Q is determined by the ratio of R_{in} to R_{L}, and bandwidth is not controllable.

Upward transform : R_{in}>R_L Downward transform : R_{in}<R_L

There are 4 types of L network

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<b>Design and Calculation </b>

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<b>Simulation </b>

Figure 1. ADS Schematic for Linear AC Analysis of Circuit

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Figure 2. L matching simulation (for the exercise)

<b>Comment: </b>

The match is perfect at the design frequency but, away from that frequency, we must accept the resulting frequency response.

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<b>2.2 Pi matching network Overview </b>

networks with a virtual resistance, RV, between the networks.

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Design and Calculation

10 20 30 40

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Figure 5. Value Table (Pi network)

<b>Simulation </b>

Figure 6. ADS Schematic for 40 Ohm Center Impedance Design

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Figure 7. Simulated Frequency Response of pi-networks for varying center Impedance

Figure 8. Increasing Zcenter beyond min {Rload,Rs} reduces the Q of match and at the same time compromises the maximum power that can be transferred at the design frequency

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<b>2.3 T matching network Overview </b>

Figure 9. T network design approach.

<b>Design and Calculation </b>

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Zcenter L1 L2 C 2000

3000 5000 10000

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<b>Simulation </b>

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Reeeeefffffererenceerenceence

Our course’s slides and books

L network and L network calculator:

-tobasics-impedance-matching-part-2

circuits/#:~:text=Overview,shape%20(see%20schematic%20below).

Three element network:

_Networks_(Steer)/06%3A_Chapter_6/6.6%3A_Multielement_Matching#:~:text=The%20three%2Delement%20matching%20network,the%20three%2Delement%20matching%20arrangement.

L network: YXXiwNPYC3lAysWpz&index=2

to Design RF and Microwave Impedance Matching Networks :


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