Design of Low-Density Parity-Check Codes for Multi-Input Multi-Output Channels

摘要

A combined coding and modulation scheme is studied for transmitting information reliably over multi-input multi-output (MIMO) fading channels. The scheme, called low-density parity-check (LDPC) modulation, combines the MIMO detector and the variable node decoder of a low-density parity-check (LDPC) code. Good LDPC degree sequences are designed by using extrinsic information transfer (EXIT) charts. LDPC modulation is shown to perform within about 1 dB of MIMO capacity when the receiver, but not the transmitter, knows the channel. The method further outperforms a UMTS standard turbo coding scheme by a wide margin when there are more transmit than receive antennas.