In this paper, we address iterative receiver processing for OFDM code division multiplexing (OFDM-CDM). The receiver algorithm we focus on is soft parallel interference cancellation in combination with a-priori demodulation. We investigate the convergence behavior of OFDM-CDM as a serial code concatenation, consisting of CDM as inner code and rate-1/2 convolutional codes as outer codes, by means of EXIT chart analysis. The EXIT charts will induce further adaptive modifications for iterative receivers in order to improve the bit error performance. As we will see, performance improvements can be mainly achieved at low signal-to-noise ratios resp. for medium bit error ranges.
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