High Frequency Amplifiers

There are several requirements for amplifier design:

1. Maximum gain design

2. Fixed gain design

3. Minimum Noise figure design (Low noise amplifier design)

The main difference is that the matching requirements of the input and output terminals are different.

The matching requirements for the maximum gain design are:

1. for the unconditionally stable S -parameter, the input and output of the conjugate matching;

2. for unstable S -parameters, match the port impedance in the stable region of the source and load reflection coefficients, while maximizing the gain (theoretically achieving a stable gain of s21/s12);

3. for fixed gain amplifier design, with the concept of equal gain circle, select the reflection coefficient of source or load on the equal gain circle;

4. for the minimum noise figure design, the source end impedance is matched to the minimum noise coefficient required impedance, the load end can be conjugate matched.

In high frequency, the Advanced Design System (ADS) is used for simulation.

Simply introduce the software using:

1.mu is used to test the stability of s -parameters (mu is more than 1 unconditionally stable),maxgain is used to test the maximum gain that the s parameter can achieve, The SMGAMMA1 is used to calculate the source reflection coefficients for conjugate matching (1 ports to the signal source end), andSMGamma2 is used to calculate the load reflection coefficients for conjugate matching (2 -port to load view).

2. Simulation Results

3. input/output port matching network design

Input Port matching requirements:

Design a matching network that will reflect the coefficients ... Matched with the corresponding impedance at

You can also match the design with the Smith Chart tool.

High Frequency Amplifiers