On the error performance of wireless systems with frequency selective fading and receiver timing phase offset

Receiver timing phase is one of the essential factors defining the performance of wireless communication systems. In this paper, we investigate the effects of timing phase offset, which is introduced by the phase difference between the transmitter clock and receiver clock, on the performance of wireless systems over frequency selective fading. With frequency domain analysis, the instantaneous signal-to-noise ratio (SNR) observed by the communication receiver is expressed as an explicit function of system timing phase offset and receiver oversampling factor. A tight performance lower bound, which corresponds to the best possible system performance under particular system configuration, is then derived by examining the statistical properties of the receiver SNR. From the analytical results, it is observed that, if the receiver sampling rate is less than the Nyquist rate of the received signal, then the system performance lower bound is a periodic function of the timing phase offset. On the other hand, the best possible performance of the oversampled system is independent of timing phase offset. Moreover, the oversampled system can use a receive filter matched to the time-invariant transmit filter instead of a statistical filter matched to the joint response of channel and transmit filter without affecting the best possible system performance. Simulation results show that the theoretical bound derived in this paper can accurately predict the performance of practical communication systems suffering from both frequency selective fading and timing phase offset