United States Patent 7,499,393
Ozluturk March 3, 2009
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Per stream rate control (PSRC) for improving system efficiency in OFDM-MIMO communication systems
Abstract
A transmitter splits a user-data stream into a plurality of sub-streams. The transmitter then adaptively selects a modulation scheme and coding rate for each of the sub-streams based on current channel conditions. Next, a plurality of sub-carriers are modulated and encoded with the sub-stream data according to the selected modulation schemes and coding rates. The modulated sub-carriers are each allocated to one or more transmit antennas for transmission. Prior to transmission, a transmission power for each of the sub-carriers is adjusted based on the channel conditions. The adaptive modulation and coding function, the sub-carrier allocation function, and the power control function are jointly controlled to optimize throughput, signal quality, and system efficiency.
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Inventors: Ozluturk; Fatih (Port Washington, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)
Appl. No.: 11/189,649
Filed: July 26, 2005
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Related U.S. Patent Documents
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Application Number Filing Date Patent Number Issue Date
60600742 Aug., 2004
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Current U.S. Class: 370/208 ; 370/335
Current International Class: H04J 11/00 (20060101)
Field of Search: 370/208,210,267,203,204,205,206,209,328,329,330,335,342,441,334,435 375/299,316,130,260,267,346,347,358 455/101
