Development of High Performance Compact Diplexer for Transportable Antenna Terminal

Abstract

This paper presents development of a compact and a robust high performance diplexer implemented using co-axial guide at S-band. It is designed to operate at a power level of around 200 W in the frequency band from 2.02 GHz to 2.3 GHz with an insertion loss better than 1.0 dB. To achieve the stringent isolation requirements between adjacent uplink & downlink frequency bands, higher order filters with a rejection of 100 dB are designed. The diplexer is used in Transportable antenna Terminal for tracking & commanding of satellites & launch vehicles. The measured results conform to the required specifications. In-addition, innovative fabrication aspects are also presented which is extremely critical to successfully achieve such high performance diplexers.