| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 714794000 | Maximum likelihood | 15 |
| 20080263430 | Data readout device and data readout method - A data readout device generates decoded data based on a decided data bit decided by performing a hard-decision on likelihood data, wherein the likelihood data is generated in accordance with an iterative decoding method corresponding to a turbo-coding process. The iterative decoding process is performed on a sampled value obtained by sampling a signal read out from a magneto-optical disk at a predetermined sampling period. The data readout device is made up of a reliability determination part and an error correcting decoder. The reliability determination part detects whether each obtained data bit was obtained from likelihood data within a predetermined range defined with respect to a histogram of log likelihood ratios. When it is detected that a data bit was obtained by a hard-decision on likelihood data within the predetermined range, the data bit is regarded as being obtained by a hard-decision whose reliability is not sufficient. In this way, the error correcting decoder can perform ECC-based decoding operations including loss-correction processes depending on respective reliability-determination results that distinguish reliabilities among respective data bits. Thus, the accuracy of decoded data is increased. The data transfer rate of transferring decoded data when reading out of the MO medium is also improved to the utmost. | 10-23-2008 |
| 20090044084 | Combined DC restoration double detection and loops - A method of double detection in a perpendicular magnetic read channel is disclosed. The method generally includes the steps of (A) generating an intermediate signal by performing a first detection on an input signal of the perpendicular read channel, the first detection having a first error rate, (B) generating a statistics signal based on the intermediate signal, the statistics signal conveying noise statistics that depend on data in the input signal and (C) generating an output signal by performing a second detection on the input signal using the noise statistics to reduce a second error rate of the second detection compared with the first error rate, wherein the first detection is independent of the second detection. | 02-12-2009 |
| 20090125793 | WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD - The invention is embodied for solving a problem of occurrence of degradation of the reception characteristic caused by the interference signal component if a symbol making a determination error is contained or if an error factor caused by a propagation channel estimation error or a hardware error (carrier frequency error, sampling frequency error) is contained at the interference canceling time in a wireless communication apparatus for iteratively decoding and receiving a spatial multiplex signal. A wireless communication apparatus | 05-14-2009 |
| 20090254797 | Iterative Signal Receiving Method and Related Iterative Receiver - Considering both performance and cost of an iterative receiver, the present invention provides an iterative signal receiving method for a wireless communications system. The iterative signal receiving method includes utilizing a channel estimating (CE) process to perform channel estimation for a received signal according to first log-likelihood ratio (LLR) data to generate second LLR data, and then generating the first LLR data according to an error correction code (ECC) decoding process and the second LLR data. When the ECC decoding process is a convolutional decoding process, the CE process is a zero-forcing process, a minimum mean square error (MMSE) process or an interpolation-based process. When the ECC decoding process is a low density parity check code (LDPC) decoding process, the CE process is a maximum likelihood (ML) process or a maximum a posteriori (MAP) process. | 10-08-2009 |
| 20090287984 | Blind Transport Format Detection Based on Decoder Metric - The present invention relates to a receiver device and method of detecting a block length of a data block in a data network, wherein a respective theoretical maximum value for a metric of a decoding operation is calculated for each of a plurality of candidate block lengths, and the calculated respective theoretical maximum value is compared to a respective actual value of the metric obtained for each of the plurality of candidate block lengths by the decoding operation. The candidate block length with the highest ratio between the respective actual value and the respective theoretical maximum value is then selected from the plurality of candidate block lengths to determine the block length of the data block. | 11-19-2009 |
| 20090307567 | WIRELESS COMMUNICATION SYSTEM, RECEIVER AND SIGNAL PROCESSING METHOD FOR RECEIVED SIGNAL - The error correction capability for wireless communication carried out involving propagation path fluctuation in time and frequency selectivity can be improved. A soft decision likelihood value inputted to an error correction decoder is multiplied by a weight determined according to the distance between the data symbol and pilot symbol corresponding to the soft decision likelihood value. Namely, the soft decision bit likelihood value corresponding to the data symbol is weighted according to the distances in time or frequency between the pilot symbol and data symbol. The weight is made smaller when the distance in time or frequency is larger. | 12-10-2009 |
| 20090319876 | MAXIMUM LIKELIHOOD DECODER AND DECODING METHOD THEREFOR - According to one embodiment, a maximum likelihood decoder includes a branch metric calculator, a processor configured to perform addition, comparison, and selection of an output from the branch metric calculator and a path metric memory, and outputs a selection signal for identifying a selection result, a path memory configured to store a time variation of the selection signal, and a path detection module configured to detect a decoding signal based on the time variation of the stored selection signal. A decoding method includes selecting operation modes of at least one of the branch metric calculator, the processor, and the path memory between a first operation mode in which an operation is performed at a channel rate frequency and a second operation mode in which an operation is performed at a specific frequency lower than the channel rate frequency. | 12-24-2009 |
| 20100095189 | METHODS AND SYSTEMS FOR MODIFIED MAXIMUM-LIKELIHOOD BASED TBCC DECODING - A method and apparatus for decoding of tailbiting convolutional codes (TBCC) are disclosed. The proposed modified maximum-likelihood TBCC decoding technique preserves error correction performance of optimal maximum-likelihood based TBCC decoding, while the computational complexity is substantially decreased since a reduced number of decoding states has been evaluated. Compare to other sub-optimal TBCC decoding algorithms, modified maximum-likelihood TBCC decoding achieves improved packet error rate performance with similar computational complexity. | 04-15-2010 |
| 20100281347 | VITERBI DETECTOR THAT ASSOCIATES MULTIPLE DATA DEPENDENT NOISE PREDICTION FILTERS WITH EACH POSSIBLE BIT PATTERN - A Viterbi detector includes a plurality of possible bit patterns that correspond to branches of a detector trellis and a plurality of data dependent noise prediction filters, with multiple filters of different orders being associated with a given bit pattern. A method of decoding includes applying observables to a Viterbi detector that associates a plurality of data dependent noise filters with a given possible bit pattern that corresponds to a branch of the detector trellis, calculating the composite maximum likelihood branch metric by incorporating the results of filtering the observables through the associated plurality of filters, calculating the composite maximum likelihood branch metrics in the same manner for other possible bit patterns, and so forth, and associating soft output values with detected bits in the observables based on the calculated branch metrics. | 11-04-2010 |
| 20110041044 | ENCODER, DECODER, AND ENCODING METHOD - An encoder and decoder using LDPC-CC (Low Density Parity Check-Convolutional Codes) is disclosed. The encoder exhibits encoding rates realized with a small circuit-scale and a high data reception quality. In the encoder ( | 02-17-2011 |
| 20110173518 | APPARATUS AND METHOD FOR DETERMINING RELIABIILTY OF DECODED DATA IN COMMUNICATION SYSTEM - A method and apparatus for determining the reliability of decoded data in a communication system. The method includes calculating a total sum of absolute values corresponding to Log Likelihood Ratio (LLR) values of received data, generating a first value obtained by multiplying the total sum of the absolute values by a predetermined threshold value, performing iterative decoding with respect to the LLR values of the received data, generating a survived path metric value having a maximum value among all path metric values as a decoded result and generating decoded data, comparing the first value with the survived path metric value, and determining whether the decoded data has suitable reliability according to the compared result. | 07-14-2011 |
| 20130219251 | ELECTRONIC APPARATUS, RECEIVING APPARATUS, AND ERROR CORRECTION METHOD - In an electronic apparatus, a soft decision likelihood value is generated and subject to a decoding process supporting a convolutional code; and a data series is interleaved, subjected to an error correction process, and decoded data is generated. A detecting unit, based on information concerning the position of a symbol for which an error has been corrected successfully by the error correction process, estimates whether an error occurs in a symbol for which the error correction process failed and detects the position of a symbol estimated to have an error. A setting unit sets based on the decoded data and information concerning the position of the symbol estimated to have an error, a correction value of the soft decision likelihood value. The electronic device interleaves the order of a correction value series of the soft decision likelihood value and feeds the resulting correction value series back to the decoding process. | 08-22-2013 |
| 20130283134 | COMMUNICATION SYSTEM WITH BLIND DECODING MECHANISM AND METHOD OF OPERATION THEREOF - A communication system includes: a decoding-probability module for calculating a decoding likelihood with a control unit for characterizing an alternative hypothesis regarding an arriving communication; a null-probability module, coupled to the decoding-probability module, for calculating a null likelihood for characterizing a null hypothesis regarding the arriving communication; a weight-calculation module, coupled to the decoding-probability module, for generating a decision weight corresponding to the decoding likelihood, the null likelihood, or a combination thereof; a reliability calculation module, coupled to the decoding-probability module, for calculating a decoding reliability with the decision weight, the decoding likelihood, and the null likelihood, the decoding reliability corresponding to a decoded-result; and a decoding module, coupled to the reliability calculation module, for decoding the arriving communication with a decoding parameter based on the decoding reliability for communicating with a device. | 10-24-2013 |
| 20140013191 | Method and Apparatus for Decoding and Checking Tail-Biting Convolutional Code - The disclosure discloses a method and apparatus for decoding and checking a tail-biting convolutional code, so as to solve the problem of reducing a processing time delay in decoding and checking the tail-biting convolutional code in the prior art. The disclosure fully utilizes structural features of the tail-biting convolutional code to re-sort Log-Likelihood Ratio (LLR) values input into a decoder, and by reconstructing a derivative generator polynomial of a convolutional code, allows the decoder to output in serial according to a normal ordering of information bits during backtracking, that is, a first bit of an information sequence is first decoded successfully. Thus, CRC checking may be activated as soon as possible, so that part of the backtracking process and the CRC checking may be performed in parallel, thereby achieving the objective of reducing a processing time delay in decoding and checking the tail-biting convolutional code. The disclosure does not increase any hardware expense, belongs to an improvement of low cost, and does not cause any decoding performance downgrade. | 01-09-2014 |
| 20160191080 | COMMUNICATION PATH DECODING METHOD AND COMMUNICATION DECODING DEVICE - This method and device makes it possible to implement maximum likelihood decoding of a sparse graph code at low computational complexity in the maximum likelihood decoding of the sparse graph code. This is, in the maximum likelihood of decoding of the sparse graph code, a lost data decoding process by a trivial decoding method and a lost data decoding process by a Gauss elimination method are performed repeatedly and alternately. | 06-30-2016 |
