Polar Code Information Sequences for SCL Decoder Performance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polar codes' finite-length performance under Successive Cancellation (SC) decoding is not competitive with other channel coding schemes like LDPC and Turbo codes, and the Polarization Weight (PW) sequence imposes artificial reliability relationships among bit channels, which is not optimized for Successive Cancellation List (SCL) decoders.
Innovation Solution
Numerically optimized information sequences are developed for specific code lengths, accounting for the performance of SCL decoders at different Block Error Rate (BLER) levels, which are used to map information bits in polar encoding and decoding processes, enhancing the performance of polar codes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the Polarization Weight (PW) sequence is used to determine information bit locations, then the code structure is simple and easy to implement, but the finite-length performance under SC decoding is not competitive with other channel coding schemes
Solution Approach 1:
The patent changes the parameter of information sequence from the generic PW sequence to specifically optimized sequences (such as S64, S128, S256) that are tailored for different code lengths and SCL decoder configurations. This optimization of the information sequence parameter significantly improves finite-length performance while maintaining compatibility with the polar code structure.
2Adaptability or versatility
If the PW sequence is used, then the information sequence is universally applicable for any code length, but it imposes artificial reliability relationships among bit channels that are not optimized for SCL decoders
Solution Approach 1:
The patent introduces dynamic optimization by developing different information sequences (S64, S128, S256) that are specifically optimized for different code lengths and SCL decoder list sizes. Instead of using a static PW sequence for all cases, the system dynamically selects the appropriate optimized sequence based on the specific application requirements, thereby improving decoder performance without sacrificing adaptability.
3Reliability
If numerically optimized information sequences are developed for specific code lengths, then the performance for designed code lengths is improved, but the complexity of determining information bit locations increases
Solution Approach 1:
The patent applies preliminary action by pre-determining and tabulating the optimized information sequences (S64, S128, S256) for common code lengths during the design phase. These pre-computed sequences are then directly applied during encoding and decoding operations, avoiding the need for complex real-time optimization calculations and reducing the computational complexity of determining information bit locations.
Data Source
AI summary
According to some embodiments, a method of operation of a transmit node in a wireless communication system comprises performing polar encoding of a set of K information bits to thereby generate a set of polar-encoded information bits. The K information bits are mapped to the first K bit locations in an information sequence SN. The information sequence SN is a ranked sequence of N information bit locations among a plurality of input bits for the polar encoding where N is equivalent to a code length. A size of the information sequence SN is greater than or equal to K. The information sequence SN is optimized for the specific value of the code length (N). The method may further comprise transmitting the set of polar-encoded information bits.