Invention Grant
US08300739B2 Method and apparatus for generating soft bit values in reduced-state equalizers
有权
在缩减状态均衡器中产生软比特值的方法和装置
- Patent Title: Method and apparatus for generating soft bit values in reduced-state equalizers
- Patent Title (中): 在缩减状态均衡器中产生软比特值的方法和装置
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Application No.: US12427458Application Date: 2009-04-21
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Publication No.: US08300739B2Publication Date: 2012-10-30
- Inventor: Dayong Chen
- Applicant: Dayong Chen
- Applicant Address: SE Stockholm
- Assignee: Telefonaktiebolaget L M Ericsson (Publ)
- Current Assignee: Telefonaktiebolaget L M Ericsson (Publ)
- Current Assignee Address: SE Stockholm
- Main IPC: H04L27/06
- IPC: H04L27/06

Abstract:
A demodulator is provided that functions as a reduced-state equalizer and produces reliable soft bit values. According to an embodiment, soft bit values are generated for a sequence of transmitted symbols using a demodulator by updating an M-state trellis managed by the demodulator responsive to a transition from symbol time n−1 to symbol time n, where M is a function of the number of bits per symbol in the sequence of transmitted symbols. Survivor metrics associated with the M states of the trellis are saved each symbol time so that the demodulator can calculate soft bit values with regard to transitions from symbol time n+D−1 to symbol time n+D. The survivor metrics indicate the probability that each respective state represents the transmitted symbol associated with symbol time n+D−1. The trellis is traced back through to calculate soft bit values for a symbol detected at symbol time n−D based on survivor metrics saved for the M states at symbol time n−D.
Public/Granted literature
- US20100266071A1 METHOD AND APPARATUS FOR GENERATING SOFT BIT VALUES IN REDUCED-STATE EQUALIZERS Public/Granted day:2010-10-21
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