Abstract
For a conventional coded transmission scheme operating in an inter-symbol interference (ISI) channel in which the coded symbols are interleaved before being sent to the ISI channel, the extrinsic information transfer (EXIT) curve of a soft-in-soft-out (SISO) equalizer is steep for large equivalent discrete channel length of an ISI channel. In this paper, we propose to flatten the equalizer EXIT curve to match the close-to-horizontal EXIT curves of the turbo decoder or convolutional decoder optimized for AWGN channels by designing a transmission scheme which is implemented by first interleaving a codeword with two adjacent codewords and then transmitting the interleaved codewords sequentially. Hence, the thresholds of proposed system are better than those of the conventional system when the same channel codes optimized for AWGN channels are used.