Multi-antenna transmitting apparatus, multi-antenna receiving apparatus, and data re-transmitting method

A multi-antenna reception apparatus comprising:

• a reception section that receives, upon normal reception that is not reception upon a retransmission, first received signals of first Low Density Parity Check (LDPC) encoded data, and receives, upon the retransmission, a second received signal of second LDPC encoded data, the first received signals and the second received signal being received in at least one antenna, the second LDPC encoded data including a part of the first LDPC encoded data stored in a multi-antenna transmission apparatus and having a transmission error;
• a signal processing section that, upon the normal reception, separates each of the first received signals to obtain the first LDPC encoded data, and, upon the retransmission, demodulates the second received signal using a reception demodulation method, and thereby obtains the second LDPC encoded data including the retransmitted part of the first LDPC encoded data of the first received signals;
• and
• an LDPC decoding section that, upon the normal reception, performs LDPC decoding processing on the first LDPC encoded data of the first received signals, and upon the retransmission, replaces, in the first LDPC encoded data of the first received signals, the part of the first LDPC encoded data having the transmission error with the second LDPC encoded data, and performs the LDPC decoding processing on the first LDPC encoded data having the replaced part, wherein:
• the second LDPC encoded data is Kbit data obtained using top K column vectors of a check matrix H of an LDPC code, wherein the top K column vectors include the most “1”s out of n column vectors of the check matrix H, K is the number of bits in the second LDPC encoded data and 1<K<n, and n is the number of column vectors of the check matrix H.

A data retransmission method comprising:

• encoding different units of transmission data using a Low Density Parity Check (LDPC) code to generate first units of LDPC encoded data. each of the first units of LDPC encoded data being assigned to a respective antenna of a plurality of antennas;
• transmitting the first units of LDPC encoded data assigned to the plurality of antennas;
• storing for retransmission the first units of LDPC encoded data assigned to the plurality of antennas upon the first transmission;
• and
• retransmitting, upon a retransmission, only second units of LDPC encoded data, the second units of LDPC encoded data including a part of the stored first units of LDPC encoded data having a transmission error, the second units of LDPC encoded data being assigned to at least one antenna of the plurality of antennas, wherein:
• the second units of LDPC encoded data are K-bit data obtained using top K column vectors of a check matrix H of the LDPC code, wherein the top K column vectors includes the most “1”s out of n column vectors of the check matrix H, K is the number of bits in the second units of LDPC encoded data and 1<K<n, and n is the number of column vectors of the check matrix H.