DTV Broadcast Signal Multiplexing for Robust Mobile Data Reception
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current digital television systems face challenges in transmitting supplemental data due to signal degradation from noise and ghost effects, particularly in indoor environments with blockages, which can lead to errors in critical data transmission, and require compatibility with existing video/audio data broadcasting systems.
Innovation Solution
A digital television transmitting and receiving system that includes an encoder for error correction and detection, a data randomizing and expanding unit, a group formatter, and a packet formatter for enhanced data, along with a tuner, demodulator, equalizer, and frame decoder for the receiving system, to ensure robust transmission and reception of supplemental data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If supplemental data is transmitted through the same channel as video/audio data using time-division method, then the broadcast system maintains compatibility with conventional receiving systems, but the receiving performance deteriorates in poor channel environments due to noise and ghost effects
Solution Approach 1:
The patent segments the data transmission by separating supplemental data from video/audio data into different transport streams. The supplemental data is encapsulated in dedicated packets within its own transport stream, while video/audio data remains in separate transport streams. This segmentation allows conventional receivers to ignore the supplemental data stream and process only video/audio data, maintaining compatibility, while supplemental data receives dedicated error correction resources for improved reliability in poor channel conditions.
Solution Approach 2:
The patent introduces an intermediary processing layer that encapsulates supplemental data in specially formatted packets with enhanced error correction codes. This intermediary structure acts as a buffer between the supplemental data transmission requirements and the conventional broadcast system, allowing the system to maintain compatibility while providing superior error protection for critical supplemental data through additional redundancy and error detection/correction mechanisms.
2Reliability
If additional error correction encoding is applied to supplemental data, then the error ratio decreases and receiving performance improves, but the device complexity increases due to additional encoding/decoding units
Solution Approach 1:
The patent merges the error correction functionality for supplemental data into the existing transport stream processing architecture. The same encoder and decoder units that process video/audio data are also used for supplemental data, with minimal additional processing logic. The supplemental data packets are processed through the existing error correction framework by treating them as additional payload data, thereby achieving enhanced error protection without proportionally increasing device complexity.
Solution Approach 2:
The patent implements universal error correction units that can process both video/audio data and supplemental data through the same coding/decoding mechanisms. The error correction encoder and decoder are designed to handle multiple data types uniformly, applying appropriate error protection based on data type identification rather than requiring separate dedicated units for each data type, thus reducing overall system complexity while maintaining high reliability for supplemental data.
Data Source
AI summary
A method is described for transmitting broadcast signals. First encoding of mobile data for a mobile service is performed. Second encoding of the first encoded mobile data is performed. The second encoded mobile data multiplexed with main data for a main service in a time domain is transmitted. The second encoded mobile data is allocated in a mobile unit and the main data is allocated in a main unit. The second encoded mobile data is transmitted with signaling information. The signaling information includes information to detect the mobile unit and a coding rate of the mobile data.