Defect Detector and Data-Recovery Circuit for Storage Media
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Defects in data-storage media degrade the performance of high-code-rate error-correcting codes, reducing their error-correction capability and limiting the storage capacity of data-storage devices.
Innovation Solution
A data-read path that includes a defect detector and a data-recovery circuit, which identifies defective regions on the storage medium and recovers data using a LDPC decoder and channel detector, allowing for effective error correction without additional coding overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If high-code-rate error-correcting codes are used to increase storage capacity, then the storage capacity is improved, but the error-correction capability deteriorates in the presence of defects
Solution Approach 1:
The defect detector performs preliminary detection of defective regions on the storage medium before data retrieval operations. By identifying defects in advance and providing this information to the data-recovery circuit, the system can prepare appropriate recovery strategies beforehand, enabling high-code-rate codes to maintain error-correction capability even when defects are present.
2Reliability
If defect detection and data recovery mechanisms are added, then the error-correction capability is maintained, but the device complexity increases
Solution Approach 1:
The defect detector and data-recovery circuit are integrated into the existing read path of the data-storage device, merging defect detection and data recovery functions with the standard data reading operations. This integration allows the system to maintain error-correction capability without adding separate, standalone complex systems, thereby limiting the increase in device complexity.
3Reliability
If additional coding overhead is used to protect against defects, then the error-correction capability is improved, but the storage capacity is reduced
Solution Approach 1:
The system uses the existing high-code-rate error-correcting codes' own decoding information and the defect detector's identification of defective regions to enable self-recovery of data. The data-recovery circuit utilizes the syndrome information already generated during normal decoding operations, combined with defect location data, to correct errors without requiring additional coding overhead, thus preserving storage capacity while maintaining error-correction capability.
Data Source
AI summary
An embodiment of a data-read path includes a defect detector and a data-recovery circuit. The defect detector is operable to identify a defective region of a data-storage medium, and the data-recovery circuit is operable to recover data from the data-storage medium in response to the defect detector. For example, such an embodiment may allow identifying a defective region of a data-storage disk caused, e.g., by a scratch or contamination, and may allow recovering data that was written to the defective region.