US 2019/0319825 A1 · DECISION FEED-FORWARD REDUCED-STATE SEQUENCE DETECTION

Abstract

Systems and methods are disclosed for detecting sequences of symbols in a received signal in the presence of inter-symbol interference. Maximum Likelihood Sequence Detection (MLSD) is a known method for optimum detection of such sequences. To reduce the complexity of the MLSD, a Reduced-State Sequence Detection (RSSD) technique has been considered based on partitioning the states of the MLSD. In this approach, a simplified sequence detector is placed within a global decision feedback loop. The disclosed architecture shortens the feedback loop by moving the sequence detector outside the loop and converting the interaction between the two to a feed-forward manner. This is achieved through slicing the signal and closing a nested loop around the sliced bins. A further variant simplifies the detector even more by reducing the number of bins.

Claims22

Dependent claims

A sequence detector for detecting a sequence of symbols corresponding to a transmitted sequence of symbols in accordance with a sequence of samples received, the detector comprising:

a slicer for generating a binned representation of a combination of a weighting factor and a set of samples from the received sequence;
a memory element for providing a delayed version of the output of the slicer as an input to control selection of the weighting factor;
and
a reduced-state sequence detector (RSSD) comprising a branch metric calculator, a state metric calculator and a path memory,
the branch metric calculator receiving as an input the received sequence of samples, the output of the slicer, and a fed forward output of the memory element,
the state metric calculator receiving as an input the output of the branch metric calculator, and
the path memory for generating a set of estimated symbols in accordance with output of the state metric calculator and the received sequence of samples.

4 more elements

Dependencies are inferred from the claim text.

Decision feed-forward reduced-state sequence detection

Life of this patent

Decision feed-forward reduced-state sequence detection

Life of this patent

Abstract

Claims22