Waveguide power combiner demonstration for multiple high power millimeter wave TWTAs

Summary form only given. The work presented here is the results of a proof-of-concept demonstration of the power combining Ka-band waveguide circuit design and test procedure using two Ka-band TWTAs (Varian model VZA6902V3 and Logimetrics model A440/KA-1066), both of which were previously employed in data uplink evaluation terminals at 29.36 GHz for the NASA Advanced Communications Technology Satellite (ACTS) program. The characterization of the individual TWTAs and power combining demonstration were carried out over a 500 MHz bandwidth from 29.1 to 29.6 GHz to simulate the deep space network (DSN) bandwidth of 31.8 to 32.3 GHz. The input and output powers were corrected for circuit insertion losses due to the waveguide components. The RF saturated powers of both ACTS TWTAs were in the order of 120 W.