Maximum-Likelihood Timing Adjustment in Magnetic Signal Playback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing signal processing devices for magnetic information playback face challenges in balancing high precision extraction of decoding target signals with suppression of delays in adjusting extraction timing, particularly when using the decoding target signal or final decoding result for timing adjustment, leading to inefficiencies and reduced reliability.
Innovation Solution
A signal processing device that includes an extraction section, a decoding section using maximum likelihood decoding, and an adjustment section that calculates and applies a likelihood-based adjustment to the extraction timing, allowing for precise timing adjustment while minimizing delays and ensuring high reliability, even with fluctuations in the decoding target signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the final decoding result is used to adjust the extraction timing, then the precision of timing adjustment is improved, but the delay time increases
Solution Approach 1:
The patent applies preliminary action by using the decoding result of a previous frame (past data) to adjust the extraction timing of the current frame. This allows timing adjustment to be performed in advance using already-available decoding information, rather than waiting for the current frame's complete decoding. The adjustment section uses the likelihood from the previous frame's decoding result to pre-adjust timing, reducing the overall delay while maintaining adjustment precision.
2Loss of time
If the decoding target signal itself is used to adjust the extraction timing, then the delay is reduced, but the reliability of timing adjustment deteriorates
Solution Approach 1:
The patent implements feedback by using the decoding result (specifically the likelihood information) to feed back and adjust the extraction timing. The adjustment section receives the likelihood from the decoding section and uses it to correct timing errors. This feedback mechanism ensures that timing adjustments are based on reliable decoded information rather than raw signals, improving adjustment reliability while maintaining timely response.
3Loss of time
If multiple phase adjustment circuits and buffer memories are installed to reduce delays, then the immediacy of timing adjustment is improved, but the device complexity increases enormously
Solution Approach 1:
The patent applies universality by designing a single phase adjustment circuit that can handle multiple decoding patterns through software or configurable logic, rather than requiring separate hardware circuits for each pattern. The decoding section processes different patterns using the same underlying circuitry, and the adjustment section universally applies timing corrections based on the decoded likelihood, regardless of the specific pattern. This multi-functional approach maintains timing immediacy without multiplying hardware complexity.
Data Source
AI summary
The invention provides a signal processing device, including: an extraction section that extracts, from an input digital signal, a decoding target signal at an extraction timing that has been determined as a timing for extracting the decoding target signal; a decoding section that decodes the decoding target signal by estimating, by a maximum likelihood decoding, a candidate for a decoding result of the decoding target signal extracted by the extraction section and detecting a maximum likelihood decoding result; and an adjustment section that adjusts the extraction timing using a likelihood of the candidate for the decoding result estimated by the decoding section.