Sixty-percent-efficient miniature C-band vacuum power booster for the microwave power module

Results from a high-efficiency miniaturized C-band vacuum power booster (VPB) development program have resulted in the development of a miniature C-band traveling wave tube (TWT) operating at 32% circuit efficiency and 61% total efficiency at an output power in excess of 170 W at 100% duty factor. When combined with a microwave power module, this VPB results in a module DC-to-RF conversion efficiency of 51%. This high-efficiency power amplifier is particularly well suited for space and airborne applications where small size, light weight, and low thermal dissipation are required. Other parallel development of VPB's operating at lower perveance and higher power has also been pursued and has resulted in nearly identical performance of 32% circuit efficiency and 61% total efficiency at power levels in excess of 240 W at 100% duty factor. A new TWT interaction code, CHRISTINE, is benchmarked with experimental data from several of these VPB's. Simulated performance is seen to accurately predict experimental data.