A MULTIPLE UNIT STEERABLE ANTENNA 



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the antenna outputs are combined at intermediate frequency, and the 

 separately steerable lobes are obtained by branching each of the six 

 first detectors into three phase shifters and combining the outputs of 



Fig. 3 — Schematic diagram of the experimental MUSA receiver. The five phase 

 shifters 4>2, 4>3, etc., of each branch, are geared to a shaft to provide the phase shifts 

 <A, 2(t>, 3(t>, etc., of Fig. 1. The inset at the top shows the directional patterns of the 

 two branches when steered at angles of 12 and 23 degrees, at a wave length of 25 

 meters. 



the phase shifters to form three steerable branches. One branch is 

 used continuously to explore the angle range to determine at which 

 angles the waves are arriving. The other two branches are set accord- 



