Performance of spread OFDM with LDPC coding in outdoor environments

The performance of OFDM systems that utilize coding and spreading is presented. The proposed systems operate in outdoor environments and achieve coding gains through the use of low-density parity-check (LDPC) encoding. It is shown that by introducing Hadamard-Walsh spreading in coded OFDM, additional gain in performance can be attained relative to uncoded as well as LDPC coded OFDM systems. Comparable systems using convolutional codes are shown to have similar performance, although the OFDM system require additional interleaving and deinterleaving.