Patent application number | Description | Published |
20100189207 | RECOVERING DATA SAMPLES - An apparatus recovers synchronous data samples from an asynchronously over-sampled stream of data samples derived from an input signal the spectral characteristic of which is subject to variation. The apparatus comprises an FIR filter having an input for receiving the asynchronously over-sampled stream of data samples and for producing equalised asynchronous samples. A signal sample reconstruction means reconstructs the synchronous data samples from the equalised asynchronous data samples. An automatic gain control loop is responsive to the reconstructed data samples to apply gain control for producing gain controlled reconstructed samples. A timing recovery means is responsive to the gain controlled reconstructed samples to provide timing information to the signal sample reconstruction means. A coefficient adaptation control loop is responsive to equalised reconstructed asynchronous data samples substantially unaffected by the automatic gain control for adapting the FIR filter coefficients to the variations in the spectral characteristics of the input signal. | 07-29-2010 |
20120047328 | DATA DE-DUPLICATION FOR SERIAL-ACCESS STORAGE MEDIA - Data storage and retrieval methods and apparatus are provided for facilitating data de-duplication for serial-access storage media such as tape. During data storage, input data is divided into a succession of chunks and, for each chunk, a corresponding data item is written to the storage media. The data item comprises the chunk data itself where it is the first occurrence of that data, and otherwise comprises a chunk-data identifier identifying that chunk of subject data. To facilitate reconstruction of the original data on read-back from the storage media a cache ( | 02-23-2012 |
20130285720 | MULTIPLE CHANNEL PHASE DETECTION - A signal processing device to utilize multiple channel phase detection includes a first phase detector for a first Phase Locked Loop (PLL) of a first channel, the first phase detector to generate phase error information from an input of the first channel. The device also includes a second phase detector of a second PLL of a second channel, the second phase detector to generate phase error information from an input of the second channel. Both the first PLL and the second PLL are to receive phase error information from both the first phase detector and the second phase detector. | 10-31-2013 |
20130286497 | MULTI-RATE OVERSAMPLING OF ANALOG SIGNALS IN STORAGE DEVICES - Multi-rate oversampling of analog signals in storage devices is described. A method of processing an analog signal derived from a storage medium in a storage device includes: filtering the analog signal with an anti-alias filter having a fixed cut-off frequency related to a target sampling rate; sampling the analog signal using an over-sampling rate of a plurality of over-sampling rates provided by a variable-rate analog-to-digital converter (ADC) to produce an over-sampled digital signal; and filtering the over-sampled digital signal using a decimation filter of a plurality of decimation filters provided by a digital signal processor (DSP) to produce a digital signal having the target sampling rate. | 10-31-2013 |
20160005434 | WRITING DATA TO A TAPE - A method of writing data to a tape on which during a write operation successive data unit groups that comprise a plurality N of data units are written across the tape as N track portions to form N data tracks that extend in a lengthways direction of the tape. The method includes identifying data units written during the write operation that need to be rewritten and writing a rewrite data unit group that contains data units identified as needing to be rewritten. The rewrite data unit group has N track portions written across the tape to form a part of the data tracks. The N track portions contain N-n data units identified as needing to be rewritten and data unit identifier information comprising respective data unit identifiers for the N-n data units contained in at least one list of data unit identifiers. N and n are positive integers. | 01-07-2016 |