United States Patent 7,474,689
Zeira January 6, 2009
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Channel estimation for time division duplex communication systems
Abstract
A plurality of communication bursts are used to communicate data in a shared spectrum in a time slot of a time division duplex communication system. Each burst has an associated midamble sequence of a set of known sequences. A wireless communication apparatus has a receiver component configured to receive the plurality of communication bursts and to define a received vector corresponding to the received bursts. A channel estimator is provided that is configured to estimate channel information of the plurality of communication bursts by constructing a block matrix having a plurality of identical right circulant matrix blocks using the known midamble sequences and the received vector. A data detector then recovers data from the received communication bursts using the estimated wireless channel information.
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Inventors: Zeira; Ariela (Huntington, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)
Appl. No.: 11/865,268
Filed: October 1, 2007
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Related U.S. Patent Documents
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Application Number Filing Date Patent Number Issue Date
11491463 Oct., 2007 7280584
11217960 Sep., 2006 7103092
09755400 Jan., 2006 6985513
60175167 Jan., 2000
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Current U.S. Class: 375/147 ; 370/342
Current International Class: H04B 1/69 (20060101); H04B 7/216 (20060101)
Field of Search: 375/130,140,147 370/342
