ADS simulation design of class AB RF power amplifier

ADS Simulation design AB Class RF power amplifier

Power amplifier parameters ：

1） Working frequency ：2110MHz
2） gain ：26dB
3） efficiency ：58%
4） Maximum output ：36dBm（4W）
5） Third order crossover ：-34dBc
6） Leakage pressure ：28V
7） Grid voltage ：2.1V

Simulation content

1） DC simulation
2） Stability simulation
3） Load traction
4） Source traction
5） Input matching network and output matching network design
6） Schematic simulation
7） Harmonic balance simulation

Specific simulation steps

1. DC simulation

The schematic diagram of DC scanning is as follows ：

Select static work point

Here, the bias selects the leakage pressure 28V, Grid voltage 2,1V, Static circuit 184mA Design ;

2. Stability analysis

Explain RFin The function of series resistance and parallel resistance ：
You can see ,× When the resistance device is dropped , The system is in 2110MHz The stability coefficient at is less than 1;
Here, series resistance and parallel resistance are grounded mainly to improve stability , Make the stability coefficient greater than 1;

1） Series resistance can improve high frequency stability


2） The parallel resistance can improve the low-frequency stability


Here we see that the stability at low frequency is greater than 1 requirement

3. Load traction

Insert Load-pull Templates , Replace the power tube in the template with the designed power tube for load traction
Set the parameters


Then select the appropriate load impedance

4. Source traction

Insert source traction template , Replace the power tube and set the parameters


ditto , Select the appropriate source impedance to design the matching network ;

5. Input matching network design

Insert two term, Set the conjugate impedance of the complex impedance obtained by the front source traction , Design the input matching network

Use Smith Chart The tool gets the input matching network
open S Parameter emulation control , Design the input matching network S Parameter simulation

You can see in the 2110MHz It's about ,S11 Yes -54dB

6. Output matching network design

No more details here , Similar to the input matching network design

7. Schematic simulation

Place the input and output matching networks into the schematic , Add bias circuit and set S Parameter emulation control


Get in 2110MHz Situated S11 and S21 curve

8. Harmonic balance simulation

First, manually place the following components , Conduct harmonic simulation , The simulation results are as follows


Then put the above schematic diagram Term、 The earth 、 Power Supply × fall , Delete harmonic simulation control , Insert port , Generate Symbol Model


Finally, insert the harmonic balance simulation template , Conduct harmonic balance simulation


The simulation results are shown in the figure ;

If there are shortcomings , I hope you can correct me .

attach ADS Simulation document