# US 2014/0157089 A1 · Forward error correction with parallel error detection for flash memories > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0157089 A1 - Document ID: US20140157089A1 - Status: Published application - Kind: A1 - Application number: 14/086,807 - Filed: 2013-11-21 - Published: 2014-06-05 - Earliest claimed: 2009-08-18 - Assignees: ViaSat, Inc. - Applicants: Viasat, Inc. - Inventors: SAMEEP DAVE; RUSSELL FUERST; MARK KOHOOT; JIM KESZENHEIMER; WILLIAM H THESLING - Web page: https://patentgrep.com/patent/US20140157089A1 ## CPC - G06F 11/1068: {in sector programmable memories, e.g. flash disk (G06F11/1072 takes precedence)} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Methods, systems, and devices are described for forward error correction for flash memory. Encoded data from flash memory may be used to generate a number of data streams. At each of a number of error detection sub-modules operating in parallel, a different one of the data streams is processed. Each error detection sub-module may detect whether a portion of the respective received stream contains an error, and forward the portion to an error correction module. The error correction module, physically separate from the error detection sub-modules, may correct the forwarded portions of the respective received streams containing an error. The age and error rate associated with the flash memory may be monitored, and a coding rate or other aspects may be dynamically adapted to account for these factors. ## Claims ### Claim at position 1 1-25. (canceled) ### Claim 26 A method comprising: encoding data using forward error correction coding; storing the encoded data in a flash memory; retrieving the encoded data stored in the flash memory to generate a data stream; processing the data stream to correct errors in the data stream associated with the flash memory; monitoring a metric of the flash memory while repeating the encoding, the storing, the retrieving and the processing, wherein the metric represents memory performance degradation of the flash memory; determining that the monitored metric exceeds a threshold; and in response to the determination, modifying the forward error correction coding for use in subsequently encoding data for storage in the flash memory. ### Claim 27 (depends on 26) The method of claim 26, wherein the modifying comprises changing a coding rate of the forward error correction coding. ### Claim 28 (depends on 26) The method of claim 26, wherein the modifying comprises implementing more robust forward error correction coding. ### Claim 29 (depends on 26) The method of claim 26, wherein the metric is based at least in part on an aging of the flash memory. ### Claim 30 (depends on 29) The method of claim 29, wherein the metric is based on one or more of a time since manufacture of the flash memory, a time since first use of the flash memory, and an amount of use of the flash memory. ### Claim 31 (depends on 26) The method of claim 26, wherein the metric is based at least in part on an amount of errors corrected during the processing. ### Claim 32 (depends on 31) The method of claim 31, wherein the metric is based on the amount of errors corrected over a period of time. ### Claim 33 (depends on 26) The method of claim 26, wherein the retrieving, the processing and the monitoring are performed on a sector-by-sector basis of the flash memory. ### Claim 34 (depends on 26) The method of claim 26, further comprising: subsequently encoding data using the modified forward error correction coding; and storing the subsequently encoded data in the flash memory. ### Claim 35 (depends on 34) The method of claim 34, wherein the subsequently encoded data is stored in a sector of the flash memory different than that of said encoded data. ### Claim 36 (depends on 26) The method of claim 26, wherein the threshold is based at least in part on an amount of available memory within the flash memory. ### Claim 37 (depends on 26) The method of claim 26, further comprising powering-up, from an inactive mode, one more error correction sub-modules for processing the data stream in response to the determination. ### Claim 38 A system comprising: an encoder to encode data using forward error correction coding; a flash memory to store the encoded data; a decoder to retrieve the encoded data stored in the flash memory to generate a data stream, and to process the data stream to correct errors in the data stream associated with the flash memory; and a controller to: monitor a metric of the flash memory while repeating the encoding, the storing, the retrieving and the processing, wherein the metric represents memory performance degradation of the flash memory; determine that the monitored metric exceeds a threshold; and in response to the determination, modify the forward error correction coding for use by the encoder in subsequently encoding data for storage in the flash memory. ### Claim 39 (depends on 38) The system of claim 38, wherein the controller changes a coding rate of the forward error correction coding to modify the forward error correction coding. ### Claim 40 (depends on 38) The system of claim 38, wherein the controller implements more robust forward error correction coding to modify the forward error correction coding. ### Claim 41 (depends on 38) The system of claim 38, wherein the metric is based at least in part on an aging of the flash memory. ### Claim 42 (depends on 41) The system of claim 41, wherein the metric is based on one or more of a time since manufacture of the flash memory, a time since first use of the flash memory, and an amount of use of the flash memory. ### Claim 43 (depends on 38) The system of claim 38, wherein the metric is based at least in part on an amount of errors corrected during the processing. ### Claim 44 (depends on 43) The system of claim 43, wherein the metric is based on the amount of errors corrected over a period of time. ### Claim 45 (depends on 38) The system of claim 38, wherein the decoder retrieves the encoded data and processes the data stream on a sector-by-sector basis of the flash memory, and the controller monitors the metric on a sector-by-sector basis of the flash memory. ### Claim 46 (depends on 38) The system of claim 38, wherein: the encoder subsequently encodes data using the modified forward error correction coding; and the flash memory stores the subsequently encoded data in the flash memory. ### Claim 47 (depends on 46) The system of claim 46, wherein the flash memory stores the subsequently encoded data in a sector different than that of said encoded data. ### Claim 48 (depends on 38) The system of claim 38, wherein the threshold is based at least in part on an amount of available memory within the flash memory. ### Claim 49 (depends on 38) The system of claim 38, further comprising powering-up, from an inactive mode, one more error correction sub-modules for processing the data stream in response to the determination.