Approximate analysis of DF ambiguity probabilities for an interferometer direction-finding system using gamma distributions

To obtain high direction-finding (DF) accuracy in electronic warfare applications, it is necessary to maximise the number of effective data points with a small angle-of-arrival error. Thus, a method to obtain the DF ambiguity probability for the selected set of array spacing is required. In this Letter, a novel method to obtain DF ambiguity probabilities for four- and five-element arrays by using gamma distributions is presented. The DF ambiguity probability obtained by the proposed method for the five-element array was in good agreement with the results of simulations. For the four-element array, the proposed method produced data that showed approximate agreement with the results of simulations. Thus, the proposed method should be useful for future applications.