Patent ID: 8391392

Claim:
A method for communication, comprising: configuring a communication system that includes a transmitter and a receiver with first precoding matrices for mapping onto N transmit antenna ports of the transmitter R1 data streams, R1≦N, each of at least some of the first precoding matrices derived from respective second and third precoding matrices configured for mapping onto respective numbers of transmit antenna ports that are less than N, and defining a set of the precoding matrices for mapping r data streams onto the N transmit antenna ports, r<R1, each precoding matrix in the set comprising a subset of columns of a given matrix selected from the first precoding matrices, while including in the set a candidate precoding matrix when the candidate precoding matrix cannot be expressed as a weighted permutation of the columns of another precoding matrix in the set; mapping the data streams onto the N transmit antenna ports using a precoding scheme based on one of the first precoding matrices; and transmitting the mapped data streams over the N transmit antenna ports from the transmitter to the receiver.