Second order iterative CDMA receivers: performance analysis and parameter optimisation

We derive an expression for the signal-to-interference-plus-noise ratio (SINR) of a second order iterative receiver. We focus on a second order linear iterative receiver which converges to the linear minimum mean squared error receiver as the number of stages increases. The SINR is given in terms of the system loading, the two receiver parameters, the number of stages and the signal-to-noise ratio. We can now estimate the bit error rate performance of iterative receivers. Finally, we perform a numerical optimisation of the SINR with respect to the parameters of the resulting second order linear iterative receiver. Within this iterative framework we can achieve performance close to the optimal linear multistage receiver