Polar Channel Coding Using CRC Bit Placement for Receiver Identification
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Solution Overview
Problem
Polar codes in wireless communication systems face efficiency issues when used without CRC, particularly in low information bit scenarios, leading to decreased transmission efficiency compared to Tail-Biting Convolutional Codes, and simply removing CRC in traditional LTE systems renders error check and target receiver identification functions impossible.
Innovation Solution
A method that generates a third bit block by combining first and second bit blocks, where the position of bits in the third block is adjusted based on the number of associated bits, allowing for unequal error protection and improved decoding accuracy by using CRC bits as both an outer code and for error checking and target receiver identification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If CRC is used in polar code for error check and target receiver identification, then reliability is improved, but transmission efficiency deteriorates due to lower throughput compared to Tail-Biting Convolutional Codes
Solution Approach 1:
The patent makes CRC bits serve multiple functions: they act as outer code for error correction, error check bits for reliability verification, and target receiver identification markers. This multi-functionality allows the system to maintain reliability while improving transmission efficiency by reducing redundant bits.
Solution Approach 2:
The patent combines CRC bits with information bits into a unified bit block structure, where CRC bits are positioned at specific locations within the same block rather than being separate overhead. This merging reduces total transmission length while maintaining both error correction and identification functions.
2Productivity
If CRC is removed from polar code to improve transmission efficiency, then productivity is improved, but reliability deteriorates as error check and target receiver identification become impossible
Solution Approach 1:
By making CRC bits multi-functional (outer code + error check + identification), the system achieves high transmission efficiency without sacrificing reliability, as all three functions are fulfilled within the same bit structure.
Solution Approach 2:
The patent changes the functional parameters of CRC bits from single-function to multi-function, allowing the same bits to serve multiple purposes simultaneously, thereby maintaining reliability while improving efficiency.
3Device complexity
If all bits are treated equally in polar code, then device complexity is reduced, but manufacturing precision deteriorates as unequal error protection cannot be provided for bits with different importance
Solution Approach 1:
The patent applies different error protection strategies to different bits based on their importance and position. CRC bits at specific positions receive enhanced protection through the outer code structure, while other bits use standard polar coding, providing localized quality optimization without overall system complexity increase.
Data Source
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AI summary
The disclosure discloses a method and device in UE and a base station for channel coding. A first node first determines a first bit block and then transmits a first radio signal, wherein bits of the first bit block are used to generate bits of a second bit block, a third bit block comprises bits of the second bit block and the first bit block, and the third bit block is used to generate the first radio signal. The first bit block, the second bit block and the third bit block comprise P1, P2 and P3 bits, respectively.