Use of the WeissWeinstein bound to compare the directionfinding performance of sparse arrays
Abstract
Weiss and Weinstein have recently derived a new lower bound on random parameter estimation error. This bound is used to develop a criterion for comparing two sparse array configurations. The arrays are first adjusted in size so that their directionfinding (DF) accuracies at high element signaltonoise ratio (ESNR) are the same when averaged over all possible directions of arrival in the hemisphere. Then their threshold ESNR's are calculated using the WeissWeinstein bound. The array having the lower threshold ESNR is judged the better array. As an example of the application of the bound, three 7element arrays, a circle, a spiral, and an Lshaped array are compared. The bound is also extended to the case of switched subarrays, where data are collected from several subarrays sequentially in time and processed as a unit. The purpose is to achieve DF accuracy approaching that of the full array while reducing the number of signal processing channels. An example, using five receivers on the 7element spiral array, shows that this is indeed possible.
 Publication:

Massachusetts Inst. of Tech. Report
 Pub Date:
 August 1993
 Bibcode:
 1993mit..reptS....D
 Keywords:

 Antenna Arrays;
 Direction Finding;
 Radar Signatures;
 Signal Processing;
 Signal To Noise Ratios;
 Criteria;
 Radar Receivers;
 Random Errors;
 Communications and Radar