EXIT Chart Evaluation of a Receiver Structure for Multi-User Multi-Antenna OFDM Systems

Date Added: Oct 2009
Format: PDF

In this paper, the authors evaluate, by means of EXtrinsic Information Transfer (EXIT) charts, an iterative receiver that has emerged as a promising candidate for non-coherent multi-user multi-antenna OFDM systems. The receiver performs parallel interference cancellation (followed by linear filtering) and channel estimation, using soft symbols obtained from a bank of single-user decoders. For the sake of conceptual clarity they study a system with two single antenna users and a receiver with two antennas, and they demonstrate how the convergence behavior of the receiver can be visualized using paired three dimensional EXIT surfaces. Their results show that the actual decoder trajectories obtained through simulations are well predicted from the EXIT charts.