Clustered-Cavity Approach for the Performance Improvement of a Ka-Band Second-Harmonic Gyroklystron Amplifier

The clustered-cavity approach has been discussed to demonstrate the bandwidth enhancement of a previously reported experimental Ka -band, second-harmonic, two-cavity gyroklystron amplifier. A generalized analytical clustered-cavity approach has been developed and then applied to enhance the bandwidth characteristics of a two-cavity gyroklystron amplifier. To validate the analytical results, the device simulation has also been carried out using commercial PIC simulation code, CST Particle Studio. The saturated output power of ~265 kW, the efficiency of ~18.4%, and the gain of ~17.07dB have been obtained in the case of both, cluster-cavity gyroklystron analysis and simulation. The clustered-cavity gyroklystron bandwidth has been achieved as ~56 MHz, which is approximately double that reported using the conventional cavity case, i.e., ~28 MHz. The obtained results show that the bandwidth of clustered-cavity gyroklystron is considerably widened along with the small increment in the RF output power, gain, and efficiency of the device.