FEC Decoding with Checksum-Guided Iteration Skipping
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Solution Overview
Problem
As optical fiber transmission rates increase, the power consumption required for FEC decoding also rises due to the iterative decoding mode, where redundant iterations result in unnecessary power waste, especially when all code words in a group have a checksum of 0, indicating successful decoding.
Innovation Solution
An FEC decoding apparatus and method that only performs a sign bit decision when all code words in a group have a checksum of 0, eliminating the need for further FEC decoding and reducing power consumption by constructing a new group for decoding only those code words that require restoration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If iterative decoding is performed for a fixed number of times N on all code words, then decoding reliability is improved, but power consumption increases due to redundant iterations when code words are already successfully decoded
Solution Approach 1:
The patent applies dynamics by making the decoding iteration count variable rather than fixed. The system dynamically adjusts the number of FEC decoding iterations based on the checksum status of code words. When a code word's checksum is 0 (indicating successful decoding), the system stops further iterations for that code word. This dynamic adaptation eliminates redundant computational operations while maintaining decoding reliability, directly reducing power consumption in high-speed optical fiber transmission systems.
Solution Approach 2:
The patent implements local quality by applying different decoding strategies to different code words within the same data stream. Instead of uniformly performing N iterations on all code words, the system individually evaluates each code word's checksum and applies decoding only where necessary. This localized approach ensures that successfully decoded code words (checksum=0) receive no further processing, while potentially erroneous code words continue to undergo full decoding, optimizing resource allocation and power usage.
2Reliability
If FEC decoding is performed on all code words in a group, then decoding completeness is ensured, but processing time increases due to unnecessary decoding of already successful code words
Solution Approach 1:
The patent applies preliminary action by performing checksum detection on code words before executing FEC decoding operations. This preliminary check allows the system to identify code words that have already been successfully decoded (checksum=0) and exclude them from subsequent decoding processes. By performing this preliminary assessment, the system avoids unnecessary processing time while ensuring that only code words requiring correction undergo the time-consuming FEC decoding procedure.
Solution Approach 2:
The patent implements segmentation by dividing the processing of code words into distinct groups based on their checksum status. Code words are segmented into two categories: those with checksum=0 (successfully decoded) and those with non-zero checksums (requiring decoding). This segmentation allows the system to process different segments with appropriate operations, completing decoding for the entire group while minimizing time spent on already-successful segments.
Data Source
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AI summary
Embodiments of the present invention provide a decoding apparatus and method. The method includes: obtaining a to-be-decoded group; detecting whether all code words in the to-be-decoded group meet that a checksum is 0; performing a sign bit decision on the to-be-decoded group when all the code words in the to-be-decoded group meet that a checksum is 0; detecting, when all the code words in the to-be-decoded group do not meet that a checksum is 0, whether the sign bit decision has been performed on each code word in the to-be-decoded group; performing, when there is at least one code word on which the sign bit decision has been performed in the to-be-decoded group, data restoration on each code word on which the sign bit decision has been performed; and constructing a new to-be-decoded group by using each code word obtained after the data restoration and each code word on which the sign bit decision has not been performed, to perform FEC decoding. When all the code words in the to-be-decoded group meet that a checksum is 0, FEC decoding is not performed, and only the sign bit decision is performed. That is, in a process of performing multiple times of decoding on each code word, FEC decoding is not always performed every time. This reduces power consumption required by FEC decoding.