NR LDPC Base Graph Coding With Adaptive CRC Overhead
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current 5G network channel coding technologies face inefficiencies in CRC overhead and modulation and coding scheme (MCS) optimization, particularly in NR networks, where the use of two LDPC base graphs and CRC attachment for smaller transport blocks are not fully optimized, leading to potential errors in error detection and spectral efficiency.
Innovation Solution
The solution involves generating code blocks with parity bits using cyclic redundancy checks based on applied linear error correcting code base graphs, determining the number of parity bits based on the information bits and threshold, and utilizing a nested MCS table structure to optimize channel performance, allowing for efficient CRC attachment and MCS scheme definition for both base graphs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If two LDPC base graphs are used for different transport block sizes, then coding flexibility and adaptability are improved, but system complexity and difficulty of implementation increase
Solution Approach 1:
The patent makes the first LDPC base graph universal by configuring it to support both smaller transport blocks (≤3840 bits) and larger transport blocks (>3840 bits). This is achieved by setting the base graph parameters (N1, K1, Q1) such that the first base graph can handle the full range of transport block sizes, eliminating the need for separate base graphs for different size ranges and thereby reducing implementation complexity while maintaining adaptability
2Reliability
If 24 CRC bits are attached to all transport blocks, then error detection capability is improved, but overhead and loss of information increase
Solution Approach 1:
The patent applies different CRC bit lengths based on the transport block size: 24 CRC bits are attached to larger transport blocks (>3840 bits) where comprehensive error detection is needed, while only 16 CRC bits are attached to smaller transport blocks (≤3840 bits) where full 24-bit CRC would create excessive overhead. This localized approach optimizes the balance between error detection capability and overhead for different data sizes
3Manufacturing precision
If separate base graphs are used for different code rates, then coding precision is improved, but device complexity increases
Solution Approach 1:
The patent configures the first LDPC base graph with parameters that enable it to serve multiple code rate requirements. By setting appropriate base graph parameters (N1, K1, Q1) and using code block segmentation strategies, the first base graph can achieve precise coding for various code rates (including high code rates >0.75) without requiring separate specialized base graphs, thereby maintaining coding precision while reducing implementation complexity
Data Source
AI summary
An apparatus is provided which comprises at least one processor, at least one memory including computer program code, and the at least one processor, with the at least one memory and the computer program code, being arranged to cause the apparatus to at least perform generating a code block including information bits and parity bits, the parity bits being generated by performing a cyclic redundancy check on the information bits, determining the number of parity bits used in generating the code block based on an applied linear error correcting code base graph and/or based on the number of the information bits, and encoding the code block by using the applied linear error correcting code base graph.