LDPC Frame Mapping for Shaping Gain Across 16K and 64K Modes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The DVB-NGH system faces challenges in obtaining maximum shaping gain due to the direct adaptation of non-uniform mapping patterns from the DVB-T2 system, particularly with the 64 k mode, L1 signaling information, and MIMO profiles, which results in suboptimal error correction capabilities and increased C/N ratios.
Innovation Solution
A transmission device and method that selectively maps error correction coded frames in non-uniform patterns based on predetermined bit lengths, even if coding rates are identical, allowing for efficient shaping gain optimization by defining different non-uniform mapping patterns for various LDPC code lengths and transmission systems like SISO, MISO, and MIMO.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If non-uniform mapping patterns from DVB-T2 system are directly adapted to DVB-NGH system, then implementation simplicity is improved, but shaping gain and error correction capability deteriorate
Solution Approach 1:
The patent applies local quality by defining different non-uniform mapping patterns tailored to specific DVB-NGH scenarios (64 k mode, L1 signaling information, MIMO profiles) rather than using a universal mapping pattern from DVB-T2. Each scenario receives optimized mapping characteristics appropriate to its specific requirements, achieving both implementation feasibility and performance optimization.
Solution Approach 2:
The patent changes the mapping pattern parameters specifically for DVB-NGH system requirements. By adjusting the non-uniform mapping patterns according to DVB-NGH's code lengths, modulation schemes, and transmission profiles, the system achieves optimal shaping gain while maintaining error correction capability, resolving the contradiction between simplicity and performance.
2Device complexity
If identical non-uniform mapping patterns are used for different code lengths, then system complexity is reduced, but shaping gain optimization deteriorates
Solution Approach 1:
The patent defines specific non-uniform mapping patterns for different LDPC code lengths (16 k, 64 k modes) and transmission profiles. Each code length receives a customized mapping pattern optimized for its characteristics, achieving maximum shaping gain without significantly increasing system complexity through systematic pattern design.
3Ease of operation
If uniform mapping patterns are used across all transmission systems, then ease of operation is improved, but transmission efficiency and adaptability to C/N ratios deteriorate
Solution Approach 1:
The patent introduces dynamic adaptation by defining different non-uniform mapping patterns for different transmission systems (SISO, MISO, MIMO) and profiles. The system can dynamically select the appropriate mapping pattern based on the transmission mode and channel conditions (C/N ratios), optimizing transmission efficiency while maintaining operational simplicity through standardized pattern definitions.
Data Source
AI summary
An FEC coder in a transmission device according to an exemplary embodiment of the present disclosure performs BCH coding and LDPC coding based on whether a code length of the LDPC coding is a 16 k mode or a 64 k mode. A mapper performs mapping in an I-Q coordinate to perform conversion into an FEC block, and outputs pieces of mapping data (cells). The mapper defines different non-uniform mapping patterns with respect to different code lengths even an identical coding rate is used by the FEC coder. This configuration improves a shaping gain for different error correction code lengths in a transmission technology in which modulation of the non-uniform mapping pattern is used.