LDPC Encoder Structure for Co-Channel Robust TV Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current terrestrial TV broadcasting systems face significant co-channel interference issues, leading to white spaces where frequency reuse is not possible, resulting in deteriorated spectrum efficiency, especially in areas where timing and frequency synchronization between signals are not guaranteed.
Innovation Solution
A new Low Density Parity Check (LDPC) code with a length of 16200 and a code rate of 5/15 is developed, utilizing a specific LDPC encoding technique that includes a systematic part, a first parity part, and a second parity part, with a sequence structure that allows efficient encoding and decoding, specifically designed for terrestrial cloud transmission systems to mitigate co-channel interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If terrestrial TV broadcasting uses conventional transmission technology, then signal transmission is simple, but co-channel interference occurs and white spaces are generated reducing spectrum efficiency
Solution Approach 1:
The patent applies parameter changes by implementing a specific LDPC code with length 16200 and code rate 5/15, which changes the error correction capability parameters to enable robust signal reception in overlapping areas, thereby eliminating white spaces and improving spectrum efficiency without causing co-channel interference
2Loss of energy
If LDPC code with length 16200 and code rate 5/15 is used, then spectrum efficiency is improved by enabling frequency reuse, but device complexity increases due to specific encoding requirements
Solution Approach 1:
The patent applies segmentation by dividing the LDPC codeword into a systematic part (5400 bits) and a parity part (10800 bits), and further dividing the parity part into first parity bits (720 bits) and second parity bits (10080 bits). This segmentation allows for structured encoding using circulant permutation matrices, making the complex encoding process more manageable and efficient
3Loss of energy
If receiver demodulates cloud broadcast signals in overlap areas, then frequency reuse is enabled, but reception robustness deteriorates due to co-channel interference and synchronization issues
Solution Approach 1:
The patent applies beforehand cushioning by using LDPC coding with a code rate of 5/15, which provides strong error correction capability before the signal is transmitted. This pre-protection allows the receiver to robustly demodulate signals in overlapping areas despite co-channel interference and synchronization issues, ensuring reliable reception
Data Source
AI summary
A low density parity check (LDPC) encoder, an LDPC decoder, and an LDPC encoding method are disclosed. The LDPC encoder includes first memory, second memory, and a processor. The first memory stores an LDPC codeword having a length of 16200 and a code rate of 5/15. The second memory is initialized to 0. The processor generates the LDPC codeword corresponding to information bits by performing accumulation with respect to the second memory using a sequence corresponding to a parity check matrix (PCM).