The Future Architecture Of Broadband High Power RF And Microwave Amplifiers

Let’s face it, the high power amplifier is not linear enough. Low power systems perform much better but when you start combining transistors to make modules, you lose fidelity. When those modules are combined for even more power, the linearity degrades further.

In this technical brief I’ll be discussing an approach and architecture that will improve linearity for solid state high power RF and microwave amplifiers by orders of magnitude, whether class A or class AB topologies, although the fundamental principles can also be applied to TWT and MPM amplifiers as well.

For certain, it will never be the RF component manufacturers who solve this problem. Linear performance is relative and it’s the low power, non-combined, RF device linearity that sets the bar for what is considered the best achievable linearity performance. However, since the high power system amplifier combines devices the system amplifier linearity will always be inferior to the individual device. In other words, the high power system amplifier will always fall well short of desired linearity, even as RF semiconductors and other components in the RF path improve.