Robustness Analysis of 5-Element Overlapped Linear Subarrays for Wide Angular Scanning Applications

Abstract

A phased array design method with a wide scanning angle composed of several integrated subarrays to mitigate scan loss (SL) and side lobe level (SLL) problems has been previously reported in the literature. This paper discusses the robustness of the overlapped subarray, one of the subarrays for SL and suppressing SLL in the phased array if one of the elements or the feeder is damaged. Such a damage potentially causes changes in the directivity pattern of the subarray and the full array. Robustness analysis in the paper needs to be carried out for four cases. In the first case, one of the two edge elements, namely elements 1 and 5, is damaged, while in the second case, one of the elements 2 and 4 is damaged. Because element three is overlapped and is supplied by two suppliers, in the third case, the analysis needs to be carried out in conditions where element three is damaged or in case four if one of the suppliers is disconnected. The decrease in reliability of the subarray overlap design under poor conditions affects the range of angles of the scan direction, which increases in magnitude to close to 6 dBi.