LTE-advanced transmit diversity decoders

A processor, comprising:

• a multiple-input-multiple-output (MIMO) channel estimation module that generates estimates of channel matrix elements with respect to C channels, C being a positive integer greater than 1;
• and
• a MIMO receiver processing module coupled to the MIMO channel estimation module, the MIMO receiver processing module configured to:
• receive a first input that includes signals transmitted by M transmit antennas on the C channels and received by N receive antennas, M and N each being a positive integer greater than 1;
• receive, from the MIMO channel estimation module, a second input that includes the estimates of channel matrix elements with respect to C channels;
• and generate an output that includes at least an estimate of a transmit signal transmitted by one of the M transmit antennas on one of the C channels based at least in part on the first and the second inputs, wherein, when M=4 and N=2, the MIMO receiver processing module generates the output according to an algorithm expressed as follows:
• s(1)=[h*(1,1)r(1,1)+h(1,3)r*(1,2)+h*(2,1)r(2,1)+h(2,3)r*(2,2)]/D(1)
• s*(2)=[−h*(1,3)r(1,1)+h(1,1)r*(1,2)−h*(2,3)r(2,1)+h(2,1)r*(2,2)]/D(1)
• s(3)=[h*(1,2)r(1,3)+h(1,4)r*(1,4)+h*(2,2)r(2,3)+h(2,4)r*(2,4)]/D(2)
• s*(4)=[−h*(1,4)r(1,3)+h(1,2)r*(1,4)−h*(2,4)r(2,3)+h(2,2)r*(2,4)]/D(2)
• wherein:
• D(1)=|h(1,1)|2+|h(1,3)|2+|h(2,1)|2+|h(2,3)|2
• D(2)=|h(1,2)|2+|h(1,4)|2+|h(2,2)|2+|h(2,4)|2
• and wherein:
• s=detected frequency domain signal;
• s*=complex conjugate mathematical operation of s;
• r(k,q)=the received signal on carrier (2i+q−1) and receiver port number (k−1) for 1≦k≦2 and 1≦q≦4;
• and
• h(k,q)=the channel path transmission scaling factor in the frequency domain at carrier frequencies 2i, 2i+1, 2i+2, and 2i+3 for the port (q−1) transmitter to the port (k−1) receiver for 1≦k≦2 and 1≦q≦4.

A non-transitory computer-readable medium having a set of computer-executable instructions stored thereon that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• receiving a first input that includes signals transmitted by M transmit antennas on C channels and received by N receive antennas, M, N and C each being a positive integer greater than 1;
• receiving a second input that includes estimates of channel matrix elements;
• and
• generating an output that includes at least an estimate of a transmit signal transmitted by one of the M transmit antennas on one of the C channels based at least in part on the first and the second inputs, wherein, when M=4 and N=2, generating an output that includes at least an estimate of a transmit signal transmitted by one of the M transmit antennas on one of the C channels comprises generating the output according to an algorithm expressed as follows:
• s(1)=[h*(1,1)r(1,1)+h(1,3)r*(1,2)+h*(2,1)r(2,1)+h(2,3)r*(2,2)]/D(1)
• s*(2)=[−h*(1,3)r(1,1)+h(1,1)r*(1,2)−h*(2,3)r(2,1)+h(2,1)r*(2,2)]/D(1)
• s(3)=[h*(1,2)r(1,3)+h(1,4)r*(1,4)+h*(2,2)r(2,3)+h(2,4)r*(2,4)]/D(2)
• s*(4)=[−h*(1,4)r(1,3)+h(1,2)r*(1,4)−h*(2,4)r(2,3)+h(2,2)r*(2,4)]/D(2)
• wherein:
• D(1)=|h(1,1)|2+|h(1,3)|2+|h(2,1)|2+|h(2,3)|2
• D(2)=|h(1,2)|2+|h(1,4)|2+|h(2,2)|2+|h(2,4)|2
• and wherein:
• s=detected frequency domain signal;
• s*=complex conjugate mathematical operation of s;
• r(k,q)=the received signal on carrier (2i+q−1) and receiver port number (k−1) for 1≦k≦2 and 1≦q≦4;
• and
• h(k,q)=the channel path transmission scaling factor in the frequency domain at carrier frequencies 2i, 2i+1, 2i+2, and 2i+3 for the port (q−1) transmitter to the port (k−1) receiver for 1≦k≦2 and 1≦q≦4.