High gain deflection modulated microwave amplifiers using electric deflection

Existing deflection modulated amplifiers (gyrocons) generally demonstrate low gain (less than 25 dB) and utilize deflection by magnetic fields, In this paper we consider electric deflection and a more general deflection system composed of several uncoupled cavities in cascade, This leads to a considerable increase in gain) which becomes comparable to that in klystrons) eliminating the need for bulky dc deflection magnets previously used in magnetic deflection amplifiers. Two different types of electric deflection cavities were tested. The deflection impedance and the field profiles were measured in numerous cavities. The measurements indicate that electric deflection cavities have an effective deflection impedance between five and fifty times larger than magnetic deflection cavities, A multicavity deflection theory based on a relativistic beam formulation and a first order expansion of Maxwell's field equations was developed. Numerical data obtained from a computer evaluation show that deflection modulated RF amplifiers with high gain are feasible with a multicavity deflection system. Typical gain with three cavities is 50-55 dB.