Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
2006-02-14
2006-02-14
Phu, Phuong (Department: 2631)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
C375S341000, C714S795000, C714S796000
Reexamination Certificate
active
06999521
ABSTRACT:
A method and apparatus are disclosed for improving the processing time of reduced complexity sequence estimation techniques, such as reduced state sequence estimation. Precomputing the branch metrics for all possible symbol combinations in the channel memory makes it possible to remove the branch metrics unit and decision-feedback unit from the feedback loop, thereby reducing the critical path. A set of multiplexers select the appropriate branch metrics based on the survivor symbols in the corresponding survivor path cells. The computational load of the precomputations is reduced for multi-dimensional trellis codes by precomputing each dimension of the multi-dimensional trellis code separately. A hybrid survivor memory architecture is also disclosed for a RSSE for a channel having a channel memory of length L, where the survivors corresponding to the L past decoding cycles are stored in a register exchange architecture (REA), and survivors corresponding to later decoding cycles are stored in a trace-back architecture (TBA) or REA.
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Azadet Kameran
Haratsch Erich Franz
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