TABLE OF CONTENTS This section describes the different forms of gain and how they are calculated. If the conjugate match is not stable, it could take some time to choose a match by trial and error that results in a reasonable gain. For each try, a matching circuit would have to be designed and entered into the microwave circuit simulator. It is more efficient to use the mapping functions from Chapter 4 and calculate circles of constant gain. There are a several different ways to measure amplifier gain.
Figure 6-10 shows a signal flow diagram of a source and load. The power delivered to a load is the incident power minus the reflected power.
The power delivered to a load by a transmission line with a perfectly matched source is
When the source is not matched, the power delivered to a load is
When an amplifier is inserted between a generator and a load, it is important to know how much the signals will be amplified. There could be reflections from the load, the generator, or the input and output of the two-port. This creates an opportunity to describe the gain of the amplifier in several different ways.
Power gain is usually expressed by one of the following three quantities: transducer power gain ( G t), power gain, or operating power gain, ( G p)...
