Ambiguities of symmetrical linear arrays

In this letter, we build over earlier findings on the ambiguous behavior of the symmetrical linear arrays, which are used for the estimation of direction of arrival. These ambiguities arise due to the structure of the array and have direct impact on the uniqueness of the estimates. For a given array configuration, there may exist many such ambiguous sets of directions, which give non-unique estimates. We identify these ambiguous generator sets for a given symmetrical linear array. A new concept of ambiguous generator function is used to study the array ambiguities. The theoretical aspect of this investigation is followed by methods to calculate these ambiguous sets and is supported by a number of representative examples.