A cylindrical array for the TACAN system

A new cylindrical array has been developed for the TACAN ground antenna application. The technical requirements are unique since the circumferential radiation pattern is quasi-omnidirectional with multiple lobes and must be rotated at a precise rate. This is accomplished by electronically modulating the azimuth aperture distribution. Thus the antenna is a system including a specialized cylindrical array, a modulating RF feed network, and the associated electronic generator providing the required modulation and reference signals. Theoretical and practical design considerations are presented using a mathematical model of the antenna. This model describes the characteristic behavior and actual performance of the cylindrical array. The antenna´s physical characteristics and design features are described, and measured array performance is presented in detail and compared to the system requirements. Operational performance data accumulated during actual flight test evaluation is presented briefly.