Adaptive CRC Length for Reliable Control Information Transmission
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Solution Overview
Problem
Existing information transmission methods in LTE systems, despite using cyclic redundancy check (CRC) codes, still face the possibility of errors in transmission even when the CRC check succeeds, leading to unreliable data transfer.
Innovation Solution
Determine the length of the CRC code based on the length of control information, using specific thresholds and generator polynomials to generate and attach the CRC code to the information, thereby improving transmission reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fixed-length CRC code is added to original information, then the transmission reliability is improved, but the possibility of transmission errors still exists even when CRC check succeeds
Solution Approach 1:
The patent applies dynamics by making the CRC code length variable rather than fixed. The CRC length is dynamically adjusted based on the length of the control information being transmitted. When control information is short (≤11 bits), no CRC is added; when it is medium length (12-56 bits), an 8-bit CRC is added; when it is long (>56 bits), a 16-bit CRC is added. This dynamic adaptation optimizes the balance between error detection capability and transmission efficiency for different information lengths.
Solution Approach 2:
The patent changes the parameter of CRC code length based on the information length. By modifying this key parameter dynamically, the system achieves better error detection performance. The generator polynomial is also selected based on information length (gCRC_8(D) for 8-bit CRC, gCRC_16(D) for 16-bit CRC), further optimizing the error detection capability for different transmission scenarios.
2Reliability
If CRC code length is increased to improve error detection, then transmission reliability is improved, but the overhead and complexity increase
Solution Approach 1:
The patent segments the CRC encoding process into distinct cases based on control information length. It divides the encoding scenarios into three segments: no CRC for very short information (≤11 bits), 8-bit CRC for medium information (12-56 bits), and 16-bit CRC for long information (>56 bits). This segmentation allows the system to apply the appropriate level of error detection complexity for each segment, avoiding unnecessary overhead for short control information while providing enhanced protection for longer information.
Solution Approach 2:
The patent applies partial action by selectively applying CRC encoding only when necessary. For control information ≤11 bits, no CRC is added (partial application). For 12-56 bits, an 8-bit CRC is added (moderate application). For >56 bits, a 16-bit CRC is added (full application). This partial or excessive action approach ensures that the system does not over-engineer error detection for short control information while providing adequate protection for longer transmissions.
Data Source
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AI summary
Embodiments of the present invention provide an information sending method and apparatus and an information receiving method and apparatus. The sending method includes: determining a length of a cyclic redundancy check CRC code based on a length of first information, where the first information is control information, and if the length of the first information is less than or equal to a first threshold, it is determined that the length of the CRC code is a first length, or if the length of the first information is less than or equal to a first threshold and greater than a second threshold, it is determined that the length of the CRC code is a first length; generating the CRC code based on a generator polynomial corresponding to the length of the CRC code and the first information; generating second information; and sending the second information. The present invention improves reliability of information transmission.