FADING EFFECTS ON ANTENNA-ARRAYS IN CELLULAR COMMUNICATIONS

In future application of antenna arrays to wireless communications, it is envisioned that known signal waveforms (e.g., synchronization data stream) will be used for estimating the array response for all the re levant links, Once the array response is known, it will be used for se paration and reconstruction of the unknown data stream, Since the arra y response matrix is estimated with finite precision, we examine the e rror effects on the signal reconstruction errors, The results are pres ented in the form of output signal-to-interference ratio (SIR) and out put signal-to-noise ratio (SNR) for uncorrelated signals, We obtain cl osed-form expressions for the average output SNR and SIR for Rayleigh, Ricean, and Nagakami fading, It is shown that in the presence of slow ly fading channels, the diversity advantage of the array decreases as the number of signals (or interferers) increases.