The Effect of a Finite Distance Signal Source on a Rectangular Shaped Far Field Steering Applebaum Array

The performance degradation of a rectangular shaped far field steering Applebaum array due to a finite distance signal source is examined. An expression for the output Signal-to-Noise Ratio is obtained in terms of: (1) the distance between the signal and the array center, (2) the input SNR, (3) the element number and locations and (4) the two-dimensional signal direction. The approximate distance at which the output SNR is degraded by 1 dB is then determined.