Theory of the microelectronic traveling wave klystron amplifier with field emission cathode array

Summary form only given. The microelectronic modification of the traveling wave klystron (TWK) utilizes the microstrip transmission lines as the waveguide structures and field emission array (FEA) as the distributed cathode. The key operation principle of the TWK is velocity modulation and bunching in a drift space, thus there is no need in deep density modulation. In this paper, we present the results of theoretical investigation of the TWT with FEA. Theoretical formulas for gain in linear and nonlinear regimes are derived. Calculations show that for typical values of FEA parameters gain about 20-30 dB is possible in a wide ranges of frequencies (100-600 GHz). Gain saturation in nonlinear regime of large input power is studied. Finally, the TWK with an intermediate transmission line for improving gain and efficiency is considered.