Linear turbo equalization using despread values

Pulse or digital communications – Spread spectrum – Direct sequence

Reexamination Certificate

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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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Turbo code: Information From Answers.com.
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PCT International Search Report (5 pages).
PCT Written Opinion of the ISA (6 pages).

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