Polar Code Rate Matching via Generator Matrix Pruning
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Solution Overview
Problem
Existing wireless communication technologies, such as Turbo codes and LDPC codes, face challenges in achieving ideal performance for short code lengths and have high complexity, which is not suitable for IoT communications, and current polar code rate matching methods are complex and inefficient.
Innovation Solution
A method for polar encoding and rate matching that involves determining and deleting rows and columns from a generator matrix based on reliability rankings, allowing for flexible code length configuration without the need for repeated reliability calculations, thereby reducing calculation complexity and the number of stored tables.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If polar code rate matching is implemented using traditional methods (concatenation with linear block code or exhaust/greedy algorithms), then code length flexibility is achieved, but implementation complexity and calculation overhead increase significantly
Solution Approach 1:
The patent pre-calculates and stores reliability sequences for different mother code lengths before actual encoding. By performing the complex reliability calculation in advance and storing results in tables, the system avoids repeated calculations during real-time rate matching operations, thus reducing implementation complexity while maintaining code length flexibility
Solution Approach 2:
The patent creates a universal rate matching method that works for any target code length by using pre-stored reliability sequences corresponding to different mother code lengths. Instead of designing separate algorithms for different code lengths, a single unified approach using lookup tables achieves both flexibility and efficiency
2Reliability
If reliability calculation is performed repeatedly for different target code lengths, then optimal puncturing patterns are obtained, but calculation complexity and storage requirements increase
Solution Approach 1:
The patent pre-calculates reliability sequences for various mother code lengths and stores them in lookup tables. When rate matching is needed, the system simply retrieves the appropriate pre-calculated sequence based on the mother code length, avoiding repeated reliability calculations while maintaining optimal puncturing patterns
Solution Approach 2:
Instead of recalculating reliability sequences for each target code length, the patent creates copies of pre-calculated reliability sequences from the lookup tables corresponding to different mother code lengths. These copied sequences are then used directly for rate matching without further calculation, reducing both computational complexity and storage requirements
Data Source
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AI summary
Embodiments of the present invention provide a polar encoding and rate matching method, including: determining one or more to-be-deleted rows of a generator matrix, where the generator matrix is determined based on a preset mother code length, and a column in which 1 in the one or more to-be-deleted rows is located includes at least one column with a column weight being 1; deleting, from the one or more to-be-deleted rows, a row corresponding to a polarized channel with lowest reliability, and deleting, from a column in which 1 in the row is located, a column with a column weight being 1, to obtain an after-deletion generator matrix; using the after-deletion generator matrix as a generator matrix to repeat the foregoing steps, until an order of a final generator matrix is equal to a target code length; and performing encoding and rate matching on a to-be-encoded bit based on the final generator matrix. Therefore, repeated calculation of a reliability sequence is not required, and calculation complexity can be greatly reduced.