Performance of clustered OFDM with low density parity check codes over dispersive channels

A new LDPC coded clustered OFDM system with 16QAM modulation operating over a frequency selective fast fading channel is presented. Various channel estimation methods are studied and pilot-symbol-aided channel estimation with uniquely designed spacing pattern is used to obtain channel side information for fast fading. A BER of 10/sup -6/ is achieved at 12.8 dB with Doppler frequency f/sub m/ = 200 Hz and 14.8 dB with f/sub m/ = 100 Hz. The overall capacity of this system is about 1.56 bit/s/Hz. Compared with other wideband systems, it has much better performance in fading channels than the LPDC coded classical OFDM and is much simpler than TTCM-OFDM system.