Difference patterns are vital for the successful function of tracking radar employing monopulse techniques to estimate target direction. Traditional monopulse antenna pattern synthesis methods require the use of two independent distributions, e.g. Taylor and Bayliss distributions, for formation of sum and difference patterns for one antenna. Hence, these approaches require a feed network of considerable complexity. In this letter, a method for forming difference pattern in linear arrays using a very simple beamforming network and two additional elements is described. The sum pattern is determined by adding signals received by original radiating elements of the array whereas the difference pattern is determined by subtracting the output of the sum pattern from signals received from two external edge elements. The proposed method used to generate these two patterns offers significant hardware and software savings over current methods.
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