Power Optimization of IDMA Systems with Different Target BER Constraints

Interleave division multiple access (IDMA) is a promising air interface for future wireless networks. Optimization of access schemes regarding cross user aspects is also a topic of great interest for increasing efficiency. This paper introduces an optimization of the power profile for iterative parallel and successive interference cancellation (PIC/SIC) in IDMA systems. The basic approach is an optimization algorithm called differential evolution (DE). Optimized power allocation is an important means to increase the supportable load as it enhances the convergence behavior of the detector. Furthermore any additional constraint regarding the realistic modeling of communication systems can be implemented easily. In this paper different bit error rate constraints are considered and also the maximum number of iterations is taken into account. Computational complexity is reduced while the required power is barely increased. The precondition for this optimization is the analysis of the iterative detection scheme. This is done by variance transfer charts (VTC).