A HIGH-EFFICIENCY MODE COUPLER AUTOTRACKING FEED

Abstract

Datron Systems Inc. has developed a high efficiency autotrack feed series which uses a tracking mode coupler to generate track error signals. The mode coupler allows the use of a corrugated feed horn in doubly shaped or cassegrain geometries or a scaler ring feed in prime focus reflectors, to achieve extremely high overall antenna efficiencies. The low insertion loss of the mode coupler allows the incorporation of autotrack capability in an antenna system without degradation of the overall G/T or EIRP. Another feature of this feed is the excellent cross talk performance. The mode coupler is a rho-theta type tracker and as such is suitable for use in both single channel monopulse and equivalent full three channel monopulse autotrack applications. Datron has built, installed, and tested feeds of this type at S, C, and X band frequencies and is currently under contract to develop a dual K/Q band version. Datron has also integrated other components into the mode coupler feed assembly such as: amplifiers, filters, diplexers, couplers, downconverters, switches, noise sources, etc.