Patent ID: 8347168

Claim:
A wireless communication system comprising a transmitter provided with a plurality of transmitting antennas and a receiver provided with a plurality of receiving antennas transmitting and receiving information under a multi-input multi-output (MIMO) antenna system and using a non-binary LDPC code as a channel coding scheme between said transmitter and receiver, said receiver comprising: a demodulating unit for demodulating an input signal from said receiving antennas and a decoding unit at the output side of said demodulating unit for decoding said input signal according with said non-binary LDPC code, wherein the receiver makes a group of outputs of multi-value symbols expressed by symbol likelihood, output from said demodulating unit and the group of inputs of said decoding unit comprised of a non-binary LDPC code of predetermined dimension (q) match one-to-one to enable said demodulating unit and said decoding unit to be directly connected, wherein a number (Nt) of said plurality of transmitting antennas and a number of bits per modulation signal forming a signal of said information modulated by a predetermined modulation scheme and transmitted from said transmitter, constituting an order of modulation (m), are set with said dimension (q) and said demodulating unit determining said symbol likelihood (F) in accordance with the following condition equation: F k j = α ⁢ ⁢ exp [ -  y k - Ω ⁢ ⁢ x j  2 σ 2 ] (where, an index “j” expresses an order (0, 1 . . . q−1) assigned to a group of q number of inputs, an index “k” expresses the order of input of symbol likelihood in a time direction, “y k ” expresses a k-th received signal vector, “x j ” expresses a replica for a j-th transmission signal vector, “Ω” expresses a channel coefficient matrix estimated by channel coefficient estimation, “σ 2 ” expresses an average power of noise, “α” expresses a normalization constant for normalization so that a sum of F k j relating to all j becomes 1, “∥ ∥ 2 ” (norm) expresses a sum of the square of the absolute value of each element in the vector), and said number (Nt) of the plurality of transmitting antennas and said order of modulation (m) are linked with the dimension (q) based on the following condition equation: q= 2 Nt·m·n (where, n is any positive integer).