ATSC VSB Robust Stream Coding for Poor Multipath Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The ATSC VSB method for U.S-oriented terrestrial waves digital broadcasting systems experiences poor reception performance in poor channel environments due to its single carrier nature and limited error-correcting capacity, particularly in Doppler fading channels.
Innovation Solution
A digital broadcasting transmission/reception system that combines a normal stream with a robust stream, utilizing a robust data pre-processor, convolutional encoder, RS encoder, trellis encoder, and turbo decoder to enhance coding gain and improve reception performance, while maintaining compatibility with existing systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single carrier method (ATSC VSB) is used for digital broadcasting, then the system is simple and compatible with existing infrastructure, but reception performance deteriorates in poor channel environments such as Doppler fading channels
Solution Approach 1:
The transmission system is divided into two independent streams: a normal stream using conventional ATSC VSB encoding and a robust stream using enhanced error correction coding. This segmentation allows each stream to be optimized for different channel conditions while maintaining overall system compatibility.
Solution Approach 2:
The patent combines two different coding schemes (conventional trellis coding and enhanced convolutional/Rs coding) into a composite transmission system. The normal stream uses standard ATSC coding while the robust stream uses improved error correction, creating a hybrid system that maintains compatibility while enhancing reliability.
2Adaptability or versatility
If conventional trellis encoding is used in ATSC VSB, then the system maintains compatibility with existing standards, but error-correcting capacity is insufficient for poor channel environments
Solution Approach 1:
The patent merges conventional trellis encoding with enhanced error correction coding (convolutional encoding and Rs encoding) in a concatenated coding structure. This combination preserves compatibility with existing ATSC standards while adding robust error correction capability for challenging channel conditions.
Solution Approach 2:
The patent applies multiple stages of error correction coding (convolutional encoding followed by Rs encoding) before transmission. This preliminary action prepares the data with enhanced error protection before it encounters channel impairments, improving reliability without affecting compatibility.
3Reliability
If robust error correction coding is added to improve reception performance, then reliability improves in poor channels, but system complexity and processing requirements increase
Solution Approach 1:
The complex error correction process is segmented into distinct stages: convolutional encoding, Rs encoding, interleaving, and decoding. This segmentation allows each processing step to be optimized independently and implemented efficiently in the transmission and reception systems.
Solution Approach 2:
The patent introduces an intermediary robust stream that carries error-correction-enhanced data alongside the normal stream. This intermediary structure allows the complex error correction processing to be isolated to specific data paths while maintaining simplicity in the overall system architecture and compatibility with existing receivers.
Data Source
AI summary
A digital broadcasting transmission/reception system having improved receiving performance and signal processing method thereof. A digital broadcasting transmitter according to the present invention includes a data pre-processor which processed robust data and generates robust data packet of predetermined format, a TS stream generator which combines robust data packet with a normal data packet to generate a TS stream of a predetermined format, a randomizer which randomizes the TS stream output from the TS stream generator, a convolution encoder which performs convolution encoding with respect to the robust data of the data output from the randomizer, and a RS encoder which performs RS encoding with respect to the data output from the convolution g encoder. Accordingly, digital broadcasting receiving performance can be improved in a poor multipath channel, while maintaining compatibility with existing transmission/reception system.