Measurement and modelling of HF antenna gain and phase patterns and the effect on array performance

The performance of HF antenna arrays in many applications depends on the extent to which the array characteristics are known. For example, sampled-aperture direction-finding techniques require knowledge of the array manifold, i.e., the antenna amplitude and phase responses as a function of signal direction, in order to detect signals and accurately estimate their directions of arrival. The paper summarizes antenna gain and phase pattern measurements and the corresponding numerical modelling calculations conducted on a typical sampled-aperture direction-finding array. The implications are discussed