LDPC Additional Parity Generation Across Frames for Better Decoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current signal transmission methods for digital broadcasting lack efficient mechanisms to improve decoding performance and adapt to varying signal reception schemes, particularly in high-definition digital television and portable broadcasting scenarios.
Innovation Solution
A transmitter system that includes a Low Density Parity Check (LDPC) encoder, a parity permutator, a puncturer, and an additional parity generator, which uses interleaving patterns to generate additional parity bits by puncturing and rearranging LDPC codewords, enhancing decoding performance through improved parity bit selection and transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional LDPC encoding is used without additional parity generation, then transmission simplicity is maintained, but decoding performance is insufficient
Solution Approach 1:
The patent applies preliminary action by generating additional parity bits in advance and transmitting them in previous frames before the main data transmission. This allows the receiver to have redundant parity information ready for potential decoding operations, improving decoding performance without requiring complex real-time processing during active transmission.
Solution Approach 2:
The patent changes the parameter of parity bit transmission by introducing an additional parity generation mechanism that creates supplementary parity bits beyond the standard LDPC encoding. This parameter modification enhances the available redundancy for decoding while maintaining the core LDPC encoding structure, thus improving reliability without fundamentally altering the encoder design.
2Reliability
If more parity bits are transmitted in the current frame, then decoding performance improves, but transmission bandwidth efficiency decreases
Solution Approach 1:
The patent transmits additional parity bits in advance in previous frames rather than waiting until the current frame. This preliminary transmission of redundancy information allows the system to maintain high transmission efficiency in the current frame while still providing enhanced decoding capability through the pre-sent additional parity bits.
Solution Approach 2:
The patent creates additional copies of parity information by generating supplementary parity bits that are separate from the main LDPC parity bits. These copied parity elements are transmitted in previous frames, providing redundant decoding information without occupying bandwidth in the current frame, thus maintaining transmission efficiency.
3Productivity
If puncturing is applied to reduce parity bit transmission, then bandwidth efficiency improves, but decoding reliability deteriorates
Solution Approach 1:
The patent applies local quality by selectively puncturing only certain parity bits while preserving others. Specifically, the system identifies and punctures only the additional parity bits generated for previous frames, while maintaining the transmission of essential LDPC parity bits for current frame decoding. This selective approach maintains bandwidth efficiency through puncturing while preserving decoding reliability by keeping critical parity information.
Solution Approach 2:
The patent performs puncturing on additional parity bits that were generated in advance for previous frames. By puncturing only these preliminary-generated parity bits and not the essential current frame parity bits, the system achieves bandwidth efficiency through selective removal of redundant information while maintaining decoding reliability through preservation of necessary parity data.
Data Source
AI summary
A transmitter is provided. The transmitter includes: a Low Density Parity Check (LDPC) encoder configured to encode input bits to generate an LDPC codeword including the input bits and parity bits to be transmitted in a current frame; a parity permutator configured to perform parity-permutation by interleaving the parity bits and group-wise interleaving a plurality of bit groups configuring the interleaved parity bits based on a group-wise interleaving pattern including a first pattern and a second pattern; a puncturer configured to puncture some of the parity-permutated parity bits; and an additional parity generator configured to select at least some of the punctured parity bits to generate additional parity bits to be transmitted in a previous frame of the current frame, based on the first pattern and the second pattern, wherein the first pattern determines parity bits to remain after the puncturing and then to be transmitted in the current frame.