Performance of turbo product codes in OFDM systems with ICI self-cancellation over fast fading channel
17 May 2004
For the first time, the turbo product code (TPC) is combined with intercarrier interference (ICI) self cancellation to counteract noise and ICI in an orthogonal frequency division multiplexing (OFDM) system over a fast fading channel. Compared with existing forward error correction codes for reducing ICI, TPC offers more coding gain due to iterative decoding for some desired bit error rate (BER) with a low complexity decoder. The ICI self-cancellation scheme is used to reduce ICI and therefore improve the received signal-to-interference-plus-noise power ratio (SINR). High-level quadrature amplitude modulation (QAM) is used to compensate for the bandwidth efficiency lost by TPC and ICI. Therefore, a scheme integrating TPC, high-level QAM and ICI self-cancellation is proposed for a high data rate OFDM transmission system over highly mobile environments. The performance of TPC is evaluated using 16QAM and 64QAM in an OFDM system with ICI self-cancellation over the COST207 vehicular channel. Results show that, with the help of ICI self-cancellation, TPC satisfies a normal target BER requirement of 10-6 and obtains more coding gain. Compared with schemes without ICI self-cancellation, the proposed scheme is optimal in the sense of coding gain and target BER in a fast fading channel.