Time-varying channel modeling and variable-size burst for spatio-temporal interference suppression in DS-CDMA systems

Burst-by-burst equalization strategies assume that data in a burst are received under quasi-stationary channel conditions. Hence, using a fixed-size burst results in conservative transmission efficiency, since worst case scenarios must be accounted for. We investigate the potential of a variable-size burst for efficiency in time-varying environments. First, a channel model explicitly describing environment changes is developed. Analysis of variance is then proposed for tracking the channel stationarity. Based on knowledge of the channel stationarity, the burst size is adapted most advantageously. Obtained results show the feasibility of a variable-size burst to improve efficiency compared to a fixed-size counterpart.