Radiation Performance of an Experimental Phased Array

The radiation performance of an experimental phased array has been investigated. The antenna system consists of a nine element X-band linear array, digital phase shifters and a beam steering computer. Beamwidth, gain and beam direction error have been evaluated versus scan angle for 3- and 4-bit phase approximation. Results for E- and H-plane scan are compared. A phase monopulse tracking system has been added to the antenna and beam steering logic. With this system tracking of several independent targets is possible. Search and track information may be displayed simultaneously. Examples of tracking performance with digital beam steering are given. The work reported is a part of a research program jointly carried out by the MI Division of L M Ericsson in Mölndal and the Division of Network Theory at Chalmers University of Technology in Gothenburg, Sweden.