Comparison of multistage gyroamplifiers operating in the frequency-multiplication regime with gyroamplifiers operating at a given Cyclotron harmonic

The operation of gyrodevices at cyclotron harmonics is very attractive because of the possibility to reduce the magnetic field requirement by s times, where s is the cyclotron harmonic number. In recent years, two methods of harmonic operation in multistage gyroamplifiers have been actively studied: operation at a given harmonic in all stages and operation in the frequency-multiplying regime when the input stage operates at a lower harmonic than the output one. The present paper is aimed at making a comparative analysis of these two schemes of operation. To do this, a simple analytical method is developed, which allows one to qualitatively describe saturation effects in both schemes and compare such performance characteristics as the efficiency, gain, and bandwidth in both schemes. The results are of interest for evaluating the pros and cons of both schemes.