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:
May. 22, 2012
Filed:
Dec. 09, 2008
Applicants:
Keisuke Yamamoto, Kokubunji, JP;
Masaaki Shida, Hitachi, JP;
Inventors:
Keisuke Yamamoto, Kokubunji, JP;
Masaaki Shida, Hitachi, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04L 27/00 (2006.01); H04B 7/00 (2006.01); H04B 1/40 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a wireless communication system in which a sending side derives transmit weight vectors based on feedback information and carries out precoding, performance degradation is caused when the channel at the time when the transmit weight vectors are derived and the true channel are different from each other. Along with variations in the channel, the power allocation to a plurality of effective streams formed in MIMO is caused to approach asymptotically to uniform power allocation from the value determined based on the channel state information that the sending side has.