Broadcast Codeword Segmentation for Mobile Reception Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing broadcasting systems, such as DVB-T2, are optimized for fixed reception and struggle to ensure error-free data reception by mobile receivers under adverse conditions like multipath propagation and Doppler shifts, especially without feedback channels.
Innovation Solution
A transmitter system that incorporates both a basic codeword portion for regular decoding and an auxiliary codeword portion for incremental redundancy, allowing mobile receivers to use additional redundancy for error correction when necessary, while maintaining compatibility with existing standards.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional error correction coding is used optimized for fixed reception, then transmission efficiency is maintained, but error-free reception cannot be guaranteed under mobile reception conditions with multipath propagation and Doppler shifts
Solution Approach 1:
The codeword is segmented into a basic codeword portion and an auxiliary codeword portion. The basic codeword portion contains the essential data for standard decoding, while the auxiliary codeword portion provides additional redundancy specifically for mobile reception scenarios. This segmentation allows the system to maintain transmission efficiency for fixed receivers while providing enhanced reliability for mobile receivers through the auxiliary portion.
Solution Approach 2:
Different portions of the codeword are assigned different qualities/functions: the basic codeword portion is optimized for regular decoding operations, while the auxiliary codeword portion is specifically designed to provide incremental redundancy for error correction in challenging mobile reception conditions. This local differentiation allows each portion to serve its specific purpose effectively.
2Reliability
If additional redundancy is provided for mobile reception, then error correction capability is improved, but transmission bandwidth is consumed
Solution Approach 1:
Instead of providing full redundancy for all reception scenarios, the system applies partial redundancy through the auxiliary codeword portion. This portion is specifically tailored to provide the minimum necessary incremental redundancy for mobile reception conditions, avoiding the excessive bandwidth consumption that would result from providing complete redundancy for all possible scenarios.
Solution Approach 2:
The system changes the code rate parameter by providing different levels of redundancy: the basic codeword portion uses a higher code rate for efficiency, while the auxiliary codeword portion effectively lowers the overall code rate when additional error correction is needed. This parameter adjustment allows flexible adaptation to different reception conditions without permanently consuming excessive bandwidth.
3Reliability
If incremental redundancy is provided for mobile receivers, then robustness against channel impairments is improved, but system complexity increases
Solution Approach 1:
The auxiliary codeword portion is generated in advance during the encoding process, before transmission occurs. This preliminary generation of incremental redundancy allows the encoder to prepare for potential mobile reception scenarios without requiring complex real-time processing during transmission. The redundancy is pre-calculated and appended to the basic codeword, simplifying the overall encoding architecture.
Data Source
AI summary
A transmitter for broadcasting data in a broadcasting system that improves the decoding quality, if needed, comprises a data input, and an encoder for error correction code encoding the input data words into codewords, a codeword comprising a basic codeword portion and an auxiliary codeword portion, wherein said encoder is adapted for generating said basic codeword portion from an input data word according to a first code and for generating said auxiliary codeword portion from an input data word according to a second code, said basic codeword portion being provided for regular decoding and said auxiliary codeword portion being provided as incremental redundancy if regular decoding of the codeword by use of the basic codeword portion is erroneous. Further, the transmitter comprises a data mapper for mapping the codewords onto frames of a transmitter output data stream, and a transmitter unit for transmitting said transmitter output data stream.