Wireless Broadcast Coding with BCH-LDPC Shortening Patterns
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Solution Overview
Problem
In communication/broadcasting systems, existing technologies face challenges in maintaining optimal performance when shortening or puncturing bits, leading to variations in codeword performance due to channel noise, fading, and InterSymbol Interference (ISI), particularly in high-speed digital communication systems.
Innovation Solution
The method involves determining zero-padding and puncturing patterns to select shortened and punctured bits optimally, using Bose Chaudhuri Hocquenghem (BCH) encoding and Low Density Parity Check (LDPC) coding, with specific patterns for padding and puncturing to maintain performance, as defined in the Digital Video Broadcasting standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If bits are shortened or punctured to adapt to variable information word lengths, then the adaptability of the coding system is improved, but the performance of the codeword deteriorates due to suboptimal selection of shortened or punctured bits
Solution Approach 1:
The patent pre-calculates and stores optimal shortening and puncturing patterns before actual coding operations. The transmitter determines the number of zero-padding bits and punctured bits in advance, and both transmitter and receiver store these patterns for consistent reconstruction. This preliminary preparation ensures that when variable-length information words need to be coded, the system can immediately apply pre-optimized patterns rather than making suboptimal selections during real-time operation.
Solution Approach 2:
The patent implements dynamic adaptation by allowing the system to adjust the number of zero-padding bits and punctured bits based on the actual information word length. The transmitter dynamically determines these parameters according to the input data size, and the receiver dynamically reconstructs the original codeword structure using stored patterns. This dynamic adjustment mechanism enables the system to maintain optimal performance across different coding scenarios while adapting to variable information word lengths.
2Manufacturing precision
If zero-padding and puncturing patterns are used to select shortened and punctured bits, then the manufacturing precision of the coding process is improved, but the device complexity increases due to pattern storage and determination mechanisms
Solution Approach 1:
The patent uses copying by storing pre-calculated shortening and puncturing patterns in memory at both transmitter and receiver. Instead of performing complex real-time calculations to determine which bits to shorten or puncture, the system copies these pre-determined patterns from storage. The transmitter copies the appropriate pattern based on the information word length, and the receiver copies the same pattern to reconstruct the original data structure. This copying approach replaces complex real-time decision-making with simple pattern retrieval and application.
Data Source
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AI summary
An apparatus and method for transmitting and receiving data in a wireless communication is provided. The method includes determining a number of zero-padding bits, determining a number (Npad) of bit groups in which all bits are padded with zeros, padding the all bits within 0th to (Npad-1)th bit groups indicated by a shortening pattern with zeros, mapping information bits to bit positions which are not padded in Bose Chaudhuri Hocquenghem (BCH) information bits, BCH encoding the BCH information bits to generate Low Density Parity Check (LDPC) information bits, and LDPC encoding the LDPC information bits to generate a zero-padded codeword, wherein the shortening pattern is defined as an order of bit groups defined as 6, 5, 4, 9, 3, 2, 1, 8, 0, 7, 10 and 11.