Singly terminated pseudo-elliptic function filter

A recently developed multiplexer that uses singly terminated Chebyshev filters as channel filters has demonstrated such excellent performance that the concept was selected for the Intelsat V system. Weight savings can be achieved by replacing Chebyshev channel filters with pseudo-elliptic function filters. This paper describes methods for the synthesis, realization and tuning of a singly terminated pseudo-elliptic filter. An experimental model of a six-pole dual mode filter has been constructed in a cascading structure of three square waveguide cavities and tuned to the expected performance. This development enables a contiguous band multiplexer to use advanced pseudo-elliptic function filters with considerable space and weight savings.