Polar Code Puncture Patterns for Incremental Redundancy Retransmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communications, polar coded re-transmissions often require identical bits for all re-transmissions to support soft-combining, limiting incremental redundancy gain and increasing decoding complexity, leading to high processing overhead.
Innovation Solution
Implementing equivalent puncture sets by manipulating puncturing patterns for re-transmissions, where the base station determines a second puncturing pattern that is equivalent to the initial pattern, allowing for different redundancy versions and improving decoding reliability through joint decoding of initial and re-transmitted information.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If identical bits are used for all re-transmissions to support soft-combining, then decoding reliability is improved, but incremental redundancy gain is lost and decoding complexity increases
Solution Approach 1:
The puncturing pattern is segmented into multiple equivalent patterns that can be selectively applied to different re-transmissions. Each pattern segment provides different redundancy information, allowing the system to divide the re-transmission process into distinct redundancy versions rather than repeating identical bits, thus enabling incremental redundancy while maintaining manageable decoding complexity through structured pattern selection
Solution Approach 2:
The invention changes the puncturing pattern parameter across re-transmissions by selecting from multiple equivalent patterns. Instead of keeping the same puncturing pattern for all re-transmissions, the system varies the pattern parameters (which bits are punctured) while maintaining equivalence properties, thereby providing incremental redundancy information without requiring identical bit sequences and reducing the need for complex soft-combining operations
2Productivity
If different redundancy versions are used for re-transmissions to achieve incremental redundancy gain, then processing overhead is reduced, but decoding reliability may deteriorate
Solution Approach 1:
Multiple puncturing patterns are designed to be equivalent in terms of decoding performance, meaning each pattern serves the universal function of providing reliable decoding while differing in their specific redundancy information. This multi-functionality allows the system to use different patterns (different redundancy versions) without sacrificing reliability, as each pattern is guaranteed to provide equivalent decoding performance while enabling incremental redundancy and reducing processing overhead
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Wireless devices may use polar codes for encoding transmissions and may support combining transmissions to improve decoding reliability (e.g., by achieving chase combining and incremental redundancy (IR) gains). For example, an encoding device may puncture a set of mother code bits using different puncturing patterns to obtain different redundancy versions for a first transmission and a re-transmission. Each puncturing pattern may correspond to an equivalent decoding performance. In some cases, to obtain equivalent puncture sets, the encoding device may perform punctured index manipulation procedures on an initial puncturing pattern. A punctured index manipulation procedure may involve switching a binary state for a binary bit at a same binary bit index for each puncture index in a puncturing pattern. A device may receive the transmissions generated using the equivalent puncture sets and may combine the information for improved decoding reliability.