Analysis and design of interleavers for CDMA systems

In the last years, the Turbo-principle has been applied to multiuser receivers in CDMA systems. However, the role of interleavers in these Turbo-receivers has not been studied yet. In this letter, we give a notion of optimality and of mutual optimality and a way to test it. Moreover, limiting to congruential interleavers and convolutional codes, we give sufficient conditions to construct a set of mutually optimal interleavers. Also, we provide some simulations to support our results.