A Circulator Coupled 8-Channel Ka-Band Input Multiplexer design of Communication Satellites

The Ka-band multiplexer is used for the communication payload system in geostationary and/or LEO satellite payloads. This multiplexer consists of 5-pole inductive Chebyshev typed input filter, Riblet short-slot typed waveguide directional coupler, 8-pole TE113 Dual Mode cavity-elliptic channelized filters and circulators & isolators. Waveguide typed 3dB hybrid directional coupler can provide for the minimization of interferences between adjacent channels and separating signals with both even channels and odd channels respectively. This architecture with dual mode cavity typed channelized filters also will provide for a compact size than single mode cavity typed one. This paper shows the measured results on an Engineering Model of Ka-band input multiplexer used for communication satellite payload. Based on this result, the design factors of space qualified model of input multiplexer are induced.