Reed-Solomon Parity Byte Re-computation for Trellis Encoder Resets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing ATSC A53 standard for digital television broadcasting faces difficulties in supporting mobile receivers due to the need for periodic trellis encoder resets, which result in integrity violations of Reed-Solomon codewords and require inefficient re-computation of parity bytes.
Innovation Solution
A method and apparatus that identify and modify synchronization portions in data packets to compute new parity values using weighted versions of changed synchronization values, allowing for efficient re-computation of Reed-Solomon parity bytes during trellis state resets, eliminating the need for full re-encoding of data packets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If periodic trellis encoder resets are performed to maintain compatibility with legacy receivers, then reliability of transmission is improved, but device complexity and processing time increase due to required re-computation of Reed-Solomon parity bytes
Solution Approach 1:
The data packet is segmented into information bytes and parity bytes, allowing independent processing. When a trellis reset occurs, only the parity bytes need to be re-computed rather than re-encoding the entire packet, reducing processing complexity while maintaining transmission reliability.
Solution Approach 2:
The invention performs preliminary identification of which parity bytes are affected by the trellis reset condition before re-computation. This allows the system to prepare and re-compute only the necessary parity values in advance, rather than re-encoding the entire data packet, thus reducing processing time and complexity.
2Reliability
If full re-encoding of data packets is performed after trellis state reset, then integrity of Reed-Solomon codewords is restored, but processing time and productivity are reduced
Solution Approach 1:
The invention extracts and processes only the affected parity bytes separately from the rest of the data packet. By taking out only the necessary parity re-computation task rather than re-encoding the entire packet, the system maintains codeword integrity while significantly improving processing speed and productivity.
Solution Approach 2:
Instead of performing complete re-encoding of the entire data packet, the invention applies partial action by re-computing only the specific parity bytes that are affected by the trellis reset. This partial re-computation restores codeword integrity while avoiding the excessive processing time required for full re-encoding.
3Adaptability or versatility
If trellis encoder resets are implemented for mobile receiver compatibility, then adaptability of the system is improved, but loss of time occurs due to parity re-computation requirements
Solution Approach 1:
The system performs preliminary identification of affected parity bytes and prepares for their re-computation before the actual trellis reset occurs. This preliminary action minimizes the time loss by having the re-computation process already initiated or ready to execute immediately when needed, thus maintaining mobile receiver compatibility while reducing time loss.
Solution Approach 2:
The invention applies local quality by focusing computational resources only on the specific parity bytes that require re-computation due to the trellis reset, rather than uniformly processing the entire data packet. This localized approach reduces the time loss associated with parity re-computation while maintaining the adaptability required for mobile receiver compatibility.
Data Source
AI summary
An apparatus and method for encoding a signal are provided. The apparatus and method of the present disclosure identify the various portions, or bytes, of an incoming packet in a Reed-Solomon (RS) encoded packet as either data bytes, RS parity bytes, or trellis reset synchronization bytes. The data bytes are passed through without change. The trellis reset bytes are provided to a trellis encoder to determine new byte reset values. These new values are then stored and later retrieved when needed and used to modify the appropriate incoming parity bytes. The new incoming parity bytes are computed using the new trellis reset byte values multiplied by, or added to, a weighting value retrieved from a table stored in memory based on a location of the parity byte and a location of the trellis reset byte in the RS encoded packet.