BIT-ERROR PROBABILITY OF QPSK WITH NOISY PHASE REFERENCE

An approximate result is obtained for the bit-error probability of qua driphase shift keying in the presence of additive white Gaussian noise and a Tikhonov distributed-phase-reference error. The accuracy of the approximation is verified via actual numerical integration of the bit -error probability formula. The approximation is easy to compute, and shows correctly the behaviour of the bit-error probability as a functi on of the signal-to-noise ratio. In particular, it shows that, for hig h signal-to-noise ratios, the bit-error probability behaves as the rec iprocal of the square root of the former.