Designing Equalizers Based on Explicit Channel Models of Direct-sequence Code-division Multiple Access Systems

In this paper, we show how the entire process of transmission and reception in a DS-CDMA system, including the spreading, can be described as a tapped delay line with multiple inputs and a single output. We then demonstrate how this model can be used to design a fractionally spaced decision feedback equalizer with a single input and multiple outputs. In the proposed approach, long codes can be used and channel estimation can be performed in an e cient way. The suggested detector is near-far resistant and the capacity of the system is not limited by intracell interference. Monte Carlo simulations are conducted to demonstrate the superiority of the proposed approach as compared to the conventional detector. The simulation scenario constitute a heavily loaded system with multipath. Situations with and without power control are considered. Chapter