Performance of Digital Communication Systems with Adaptive Arrays.

摘要

This report examines the protection offered to digital communication systems by the LMS adaptive array. The performances of systems that use binary phase-shift-keyed (BPSK), quadrature phase-shifted-keyed (QPSK), binary differential phase-shift-keyed (DPSK), and noncoherent frequency-shift-keyed (FSK) modulation are calculated when the desired signal is corrupted by continuous wave (CW) interference. The probability of a symbol error at the system output is used as the measure of system performance. It is shown that the LMS array provides a significant degree of interference protection to each of these systems. The most protection is offered when the desired and interfering signals are spatially well separated. It is also shown that the performance generally improves as the array input bandwidth is reduced; however, for the modulation types listed above, the array input bandwidth must be several times larger than the data bandwidth if intersymbol interference is to be avoided.