Bit-error probability of uncoded QPSK transmitted over a 2-ray frequency selective Rayleigh fading channel

The authors study the error performance of uncoded quadrature phase shift keyed (QPSK) signals transmitted over a two-ray frequency selective Rayleigh fading channel. A Viterbi receiver with perfect channel state information is assumed. For a rectangular baseband pulse, it was found that the relative delay between the two arrival rays introduces a diversity effect which helps to improve the error performance over that of a one-ray, frequency non-selective fading channel