Adaptive bit-interleaved coded OFDM

Bit-interleaved coded orthogonal frequency division multiplexing (BIC-OFDM) is a popular transmission format for high and also some low data rate power line communication (PLC) systems. In this paper, we consider the problem of optimizing the BIC-OFDM transmitter based on channel information feedback from the receiver side. In particular, the problem of adaptive bit-loading, power allocation, and code (rate) selection for bit-error rate (BER) minimization is addressed. To this end, we first derive BER approximations for BIC-OFDM. The main difference between this analysis and many previous works on adaptive OFDM for PLC is that we include the effect of coding on BER. In the next step, we use the derived expression to formulate adaptive BIC-OFDM for BER minimization and show that the optimization problem can be solved efficiently using greedy-type algorithms. Finally, we propose a simple formula to predict the performance of the optimized system.