Class / Patent application number | Description | Number of patent applications / Date published |
714771000 | Tape | 13 |
20090287982 | CORRECTING ERRORS IN LONGITUDINAL POSITION (LPOS) WORDS - The invention includes a method for longitudinal position (LPOS) detection in a magnetic tape storage system for storing data upon linear tape open (LTO) magnetic storage tape, which data includes odd and even 36-bit LPOS words with error correcting ability. The method includes steps of encoding positional information onto the magnetic storage tape within the odd and even 36-bit LPOS words using each LPOS word's 8-bit sync mark field, Sy, and six of each LPOS word's 4-bit symbol fields, L | 11-19-2009 |
20100180180 | ECC INTERLEAVING FOR MULTI-TRACK RECORDING ON MAGNETIC TAPE - Conventional C2 coding and interleaving for multi-track data tape in LTO-¾ do not support recording data onto a number of concurrent tracks which is not a power of two. Higher-rate longer C2 codes, which do not degrade error rate performance, are provided. An adjustable format and interleaving scheme accommodates future tape drives in which the number of concurrent tracks is not necessarily a power of two. A data set is segmented into a plurality of unencoded subdata sets and parity bytes are generated for each row and column. The parameters of the C2 code include N | 07-15-2010 |
20110029843 | CYCLE SLIP DETECTION AND CORRECTION - A method of writing data to and reading data from a storage medium includes cycle slip detection and correction. An LDPC matrix includes a first area for cycle slip detection and correction. The first area satisfies a set of conditions such that a cycle slip at a particular position creates a pattern of parity check errors indicative of the position and polarity of the cycle slip. Writing user data to the storage medium includes encoding the user data with parity data according to the LDPC matrix. Reading the user data and the parity data from the storage medium includes decoding the user data and the parity data according to the LDPC matrix. Decoding includes, upon detecting a pattern of parity check errors indicative of the position and polarity of a detected cycle slip, correcting the detected cycle slip. | 02-03-2011 |
20110107187 | High Density Tape Drive Multi-Channel Low Density Parity Check Coding Control - An LDPC coding system includes a number of LDPC encoders and a number of LDPC decoders. The number of encoders/decoders is between one and one fewer than the total number of tracks on the high density tape are provided. The LDPC encoders are operable to break data from an incoming data sector into the data blocks to be written to the high density tape. The LDPC decoders are operable to assemble the data blocks into data sectors. | 05-05-2011 |
20110252290 | INTEGRATED DATA AND HEADER PROTECTION FOR TAPE DRIVES - A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein. | 10-13-2011 |
20120144271 | DECODING ENCODED DATA CONTAINING INTEGRATED DATA AND HEADER PROTECTION - A method for decoding encoded data comprising integrated data and header protection is disclosed herein. In one embodiment, such a method includes receiving an extended data array. The extended data array includes a data array organized into rows and columns, headers appended to the rows of the data array, column ECC parity protecting the columns of the data array, and row ECC parity protecting the rows and headers combined. The method then decodes the extended data array. Among other operations, this decoding step includes checking the header associated with each row to determine whether the header is legal. If the header is legal, the method determines the contribution of the header to the corresponding row ECC parity. The method then reverses the contribution of the header to the corresponding row ECC parity. A corresponding apparatus (i.e., a tape drive configured to implement the above-described method) is also disclosed herein. | 06-07-2012 |
20120210194 | INTEGRATED DATA AND HEADER PROTECTION FOR TAPE DRIVES - A method for integrating data and header protection in tape drives includes receiving an array of data organized into rows and columns. The array is extended to include one or more headers for each row of data in the array. The method provides two dimensions of error correction code (ECC) protection for the data in the array and a single dimension of ECC protection for the headers in the array. A corresponding apparatus is also disclosed herein. | 08-16-2012 |
20130139034 | ERROR CORRECTION IN A STORAGE ELEMENT ARRAY - An apparatus and associated method provided for a plurality of storage elements arranged and concurrently accessible in an array. A controller executes programming instructions stored in memory to append an error correction code (ECC) block to a first data block and to store the first data block with appended ECC block in a first storage element of the plurality, the appended ECC block associated with a second data block other than the first data block. | 05-30-2013 |
20130283127 | COMBINED SOFT DETECTION/SOFT DECODING IN TAPE DRIVE STORAGE CHANNELS - In one embodiment, a method includes executing a first forward loop of a detection algorithm on a block of signal samples during a first time interval, executing a first reverse loop of the detection algorithm on the block during a second time interval to produce first soft information, executing a decoding algorithm on the block during a third time interval using the first soft information to produce second soft information, executing a second forward loop of the detection algorithm on the block during a fourth time interval using the second soft information, executing a second reverse loop of the detection algorithm on the block during a fifth time interval to produce third soft information, executing the decoding algorithm on the block during a sixth time interval using the third soft information to produce a decoded block of signal samples, and outputting the decoded block of signal samples. | 10-24-2013 |
20130326311 | MAGNETIC TAPE RECORDING IN DATA FORMAT USING AN EFFICIENT REVERSE CONCATENATED MODULATION CODE - In one embodiment, a method for writing data to a magnetic tape utilizing a rate-(232/234) reverse concatenated modulation code includes receiving a data stream comprising one or more data sets, separating each data set into a plurality of sub data sets, encoding each sub data set with a C2 encoding, encoding each C2-encoded sub data set with the modulation code, encoding each modulated sub data set with a C1 encoding, and simultaneously writing the encoded modulated sub data sets to data tracks of the magnetic tape. Other methods for writing data to a magnetic tape utilizing a rate-(232/234) reverse concatenated modulation code are described according to various other embodiments. | 12-05-2013 |
20150058696 | TAPE HEADER FORMAT HAVING EFFICIENT AND ROBUST CODEWORD INTERLEAVE DESIGNATION (CWID) PROTECTION - In one embodiment, a system for providing header protection in magnetic tape recording is adapted to write a codeword interleave (CWI) set on a magnetic tape including a plurality of CWIs equal to a number of tracks, wherein a data set includes a plurality of CWI sets, provide a CWI set header for the CWI set, the CWI set header including a CWI header for each CWI in the CWI set, each CWI header including at least a CWI Designation (CWID) which indicates a location of the CWI within the data set, calculate or obtain CWID parity for all CWIDs in the CWI set header, the CWID parity including error correction coding (ECC) parity, and store the CWID parity to one or more fields which are repeated for each CWI header in the CWI set header without using reserved bits in the CWI set header to store the CWID parity. | 02-26-2015 |
20160117222 | TIME MULTIPLEXED REDUNDANT ARRAY OF INDEPENDENT TAPES - Embodiments relate to a computer system for storing data on a time multiplexed redundant array of independent tapes. An aspect includes a memory device that buffers data received by the computer system to be written to a set of tape data storage devices. The data is written to the set of tape data storage devices in blocks that form parity stripes across the set of tape data storage device. Aspects further includes a tape drive that writes data to one of the set of tape data storage devices at a time in a tape-sequential manner and a processor that computes a parity value for each of the parity stripes. The tape drive writes the parity values for each of the parity stripes to a last subset of tapes of the set of tape data storage devices. | 04-28-2016 |
20160124811 | SIGNAL PROCESSING DEVICE, MAGNETIC INFORMATION PLAYBACK DEVICE, AND SIGNAL PROCESSING METHOD - 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. | 05-05-2016 |