Patent ID: 7773685

Claim:
A system comprising: a plurality of transmitters and receivers, wherein each transmitter comprises at least one transmitter element and each receiver comprises at least one receiver element and wherein one of said plurality of transmitters is configured to transmit to one of said plurality of receivers, said one of said plurality of transmitters further comprising data transmitting circuitry, determining circuitry configured to determine an estimated value based on at least one parameter of said one of said plurality of transmitters, at least one parameter of said one of said plurality of receivers, and at least one parameter of a wireless environment between said one of said plurality of transmitters and said one of said plurality of receivers, and controller circuitry configured to control said data transmitting circuitry and said at least one transmitter element in accordance with said estimated value, wherein said estimated value is a practical rank number, wherein said practical rank number is defined as the number of singular values of a matrix H above a threshold value, where H is a channel transfer matrix, and said practical rank number is no greater than the smallest of the number of said transmitter elements and the number of receiver elements of said one of said plurality of receivers.