Singular value decomposition beamforming for a multiple-input-multiple-output communication system

A communication method comprising:

• transmitting a first beamformed signal;
• observing a first observed beamformed channel in response to the first beamformed signal;
• performing a QR decomposition of the first observed beamformed channel to provide a first unitary matrix;
• and
• beamforming with the first unitary matrix to transmit a second beamformed signal.

A communication device comprising:

• a beamformer to provide n signals xi,i=1, . . . , n in response to n signals di,i=1, . . . , n where n is an integer greater than one, where the signals satisfy a relationship x=T d in which d is a column vector of dimension n having components [ d]i=di,i=1, . . . , n, x is a column vector of dimension n having components [ x]i=xi,i=1, . . . , n, and T is a n by n beamformer matrix;
• n receivers to provide during M receive time intervals M signal vectors y(i),i=1, . . . ,M , where M>1 and each y(i) may be expressed as a column vector of dimension n;
• and
• a processor to perform a QR decomposition on a n by m matrix Y(M)D where Y(M) is a n by M matrix whose ith column is y(i), and D is a determinable M by n matrix, to provide a n by n unitary matrix Q where substantially Y(M)D=QR and R is a m by m upper diagonal matrix, wherein the beamformer T is T=Q*.

A communication system comprising:

• a first communication device comprising
• a beamformer to transmit during M transmit intervals M signal vectors xd(i),i=1, . . . ,M , where M is an integer greater than one, where each xd(i) is a signal vector of dimension m substantially satisfying a relationship xd(i)=Td dd(i), where Td is a m by m beamformer matrix and each dd(i) is a column vector of dimension m chosen from a determinable sequence of M column vectors of dimension M such that a matrix Dd(M) where Dd(M)≡[ dd(1) dd(2), . . . dd(M)] is rank m ;
• and
• a second communication device comprising
• n receivers to provide during M receive time intervals M signal vectors yd(i),i=1, . . . ,M , where n is an integer greater than one, where each yd(i) may be expressed as a column vector of dimension n, where for each i=1, . . ,M , yd(i) is received in response to xd(i);
• and
• a processor to perform a QR decomposition on a n by m matrix Yd(M)Pd, where the ith column of Yd(M) is yd(i) and Pd is a M by m matrix function of Dd(M), to provide a n by n unitary matrix Q1 where substantially Yd(M)Pd=Q1R1 and R1 is am by m upper diagonal matrix.

A computer system comprising:

• a microprocessor;
• a chipset in communication with the microprocessor;
• a beamformer to provide n signals xi,i=1, . . . , n in response to n signals di,i=1, . . . , n, where n is an integer greater than one, where the signals satisfy a relationship x=T d in which d is a column vector of dimension n having components [ d]i,=di,i=1, . . . , n, x is a column vector of dimension n having components [ x]i,=xi,i=1, . . . , n, is a n by n beamformer matrix;
• n receivers to provide during M receive time intervals M signal vectors y(i),i=1, . . . ,M , where M >1 and each y(i) may be expressed as a column vector of dimension n;
• and
• a processor to perform a QR decomposition on a n by m matrix Y(M)D where Y(M) is a n by M matrix whose ith column is y(i), and D is a determinable M by n matrix, to provide a n by n unitary matrix Q where substantially Y(M)D=QR and R is a m by m upper diagonal matrix, wherein the beamformer T is T=Q*.

A communication system comprising:

• a first communication device comprising a beamformer to transmit a first beamformed signal;
• and
• a second communication device comprising:
• a receiver to observe a first observed beamformed channel in response to the first communication device transmitting the first beamformed signal;
• a QR processor to perform a QR decomposition of the first observed beamformed channel to provide a first unitary matrix;
• and
• a beamformer utilizing the first unitary matrix to transmit a second beamformed signal;
• wherein the first communication device further comprises:
• a receiver to observe a second observed beamformed channel in response to the second communication device transmitting the second beamformed signal;
• and
• a QR processor to perform a plurality of QR decompositions of the second observed beamformed channel to provide a second unitary matrix, wherein the beamformer of the first communication device utilizes the second unitary matrix to transmit a third beamformed signal.