Cyclic Wiener Filtering Based Multirate DS-CDMA Receivers

Detection methods for multiple rate Direct Sequence Code Division Multiple Access (DS-CDMA) signalling are addressed. Attention is focussed on the development of receivers based on the minimum mean squared error (MMSE). Due to the cyclostationarity of the multirate signal, a representation of the multirate signal in terms of the Fourier basis is possible. This expansion facilitates construction of the MMSE receivers. Both variable spreading gain as well as variable chipping rate DS-CDMA access schemes are considered. For the multiple chipping rate system, the effect of front-end filter bandwidth on receiver performance is studied. Simulation results are provided to compare the performance of the proposed receivers