Pulse or digital communications – Spread spectrum – Direct sequence
Reexamination Certificate
2005-12-22
2009-10-13
Lugo, David B (Department: 2611)
Pulse or digital communications
Spread spectrum
Direct sequence
C375S144000, C375S346000
Reexamination Certificate
active
07602838
ABSTRACT:
A linear turbo-equalizer for use in a CDMA receiver equalizes a despread received signal (rather than the spread received signal) to suppress self-interference resulting from coupling between transmitted symbols. In an example implementation, a linear equalizer based on a generalized-Rake (G-Rake) receiver design uses decoder feedback in forming Rake combining weights as well as in forming a self-interference estimate removed from the equalizer signal provided to the decoder. Preferably, turbo de-coding is also performed. In that case, each turbo-decoder component preferably executes one pass before feeding back information to the equalizer. This ensures that the turbo-decoder does not prematurely lock onto an incorrect code word before feeding back extrinsic information to the equalizer.
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U.S. Appl. No. 10/746,434, filed Dec. 24, 2003; Inventor: Cheng.
PCT International Search Report (5 pages).
PCT Written Opinion of the ISA (6 pages).
Bottomley Gregory E.
Cheng Jung-Fu
Lugo David B
Nixon & Vanderhye P.C.
Telefonaktiebolaget LM Ericsson (publ)
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