The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 07, 2012
Filed:
Mar. 26, 2010
Philip V. Orlik, Cambridge, MA (US);
Ron Porat, San Diego, CA (US);
Ramesh Annavajjala, Quincy, MA (US);
Man-on Pun, Cambridge, MA (US);
Philip V. Orlik, Cambridge, MA (US);
Ron Porat, San Diego, CA (US);
Ramesh Annavajjala, Quincy, MA (US);
Man-On Pun, Cambridge, MA (US);
Mitsubishi Electric Research Laboratories, Inc., Cambridge, MA (US);
Abstract
Channel state information in a closed-loop, multiple-input, multiple-output wireless networks is fed back from each mobile station to a base station by first determining a transmit covariance matrix R, and applying a singular value decomposition (SVD) R=UΣV, where U, V are left and right singular vector matrices, Σ is a diagonal matrix with singular values. The matrix V includes column vectors V. A beamforming vector v=[1 exp(jΦ)exp(j2Φ) . . . exp(jΦ)]/√{square root over (N)}] is approximated by the column vector V having a maximum magnitude, where Φ is a real number. Then, only the angle Φ is fed back using a phase modulation mapping of the components exp(jΦ) onto the associated subcarrier.