LDPC HARQ Retransmission With Dynamic Interleaving
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Solution Overview
Problem
Existing ARQ and FEC methods in wireless communication systems face challenges in maintaining high data rates and reliability, particularly as channel error rates increase, necessitating improved hybrid ARQ (HARQ) techniques for error control in next-generation Wi-Fi systems.
Innovation Solution
Implementing a method that combines LDPC-based FEC with interleaving techniques for retransmitting data, using different interleaver configurations for each retransmission based on feedback and LDPC code properties to mitigate trapping sets and improve decoder inputs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ARQ protocols are used for error control, then reliability is improved, but throughput decreases as channel error rate increases
Solution Approach 1:
The patent combines ARQ and FEC into a hybrid HARQ system, merging the reliability benefits of ARQ with the throughput preservation advantages of FEC to resolve the contradiction between reliability and throughput
2Device complexity
If the same interleaver is used for retransmission, then device complexity is reduced, but decoding performance deteriorates due to trapping sets
Solution Approach 1:
The patent introduces dynamic interleaver selection where the interleaver configuration changes based on retransmission attempt number, making the system adaptive to avoid trapping sets while maintaining manageable complexity through predefined configurations
Solution Approach 2:
The patent changes interleaver parameters (configuration) based on the retransmission attempt, using different interleaver settings for initial transmission versus retransmissions to improve decoding performance without excessive complexity
3Reliability
If multiple different interleavers are used for each retransmission, then decoding performance is improved by avoiding trapping sets, but device complexity increases
Solution Approach 1:
The patent implements a dynamic interleaver selection mechanism that adapts the interleaver configuration based on the retransmission attempt number, improving decoding performance while managing complexity through systematic parameter changes
Data Source
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AI summary
Methods and devices are disclosed for transmitting data, including segmenting a group of information bits into a set of information blocks that each include a respective plurality of the information bits; encoding, using low density parity check (LDPC) encoding, each of the information blocks to generate corresponding codewords; transmitting the codewords to a destination station; receiving a feedback message indicating that at least one of the codewords has not been successfully decoded by the destination station; interleaving the information bits of the information block that corresponds to the at least one of the codewords; encoding, using low density parity check (LDPC) encoding, the interleaved information bits to generate an interleaved codeword; and transmitting the interleaved codeword to the destination station.