| Patent application number | Description | Published |
|---|
| 20080294968 | Ultra High-Speed Optical Transmission Based on LDPC-Coded Modulation and Coherent Detection for All-Optical Network - An optical communication system includes a bit-interleaved coded modulation (BICM) coder; and a low-density parity-check (LDPC) coder coupled to the BICM coder to generate codes used as component codes and in combination with a coherent detector. | 11-27-2008 |
| 20090052907 | WAVELENGTH TRANSMISSION SYSTEM AND METHOD USING 3-DIMENSIONAL LDPC-CODED MODULATION - A transmitter and method include a LDPC encoder configured to encode source data, and a mapper configured to generate three coordinates in accordance with a | 02-26-2009 |
| 20090177945 | POLARIZATION MODE DISPERSION COMPENSATION USING BCJR EQUALIZER AND ITERATIVE LDPC DECODING - A turbo equalizer includes a Bahl-Cocke-Jelinek-Raviv (BCJR) equalizer configured to receive a transmitted signal and partially cancel inter-symbol interference (ISI) due to polarization-mode dispersion (PMD). A low-density parity check (LDPC) decoder is coupled to the BCJR equalizer to receive channel bit reliabilities therefrom. The LDPC decoder iteratively provides extrinsic soft information feedback to the BCJR equalizer to compensate for PMD. | 07-09-2009 |
| 20090199065 | GLDPC ENCODING WITH REED-MULLER COMPONENT CODES FOR OPTICAL COMMUNICATIONS - A method of encoding for optical transmission of information includes encoding information with a generalized low-density parity-check (GLDPC) code for providing coding gains, and constructing the GLDPC code with a Reed-Muller RM code as a component code, the component code being decodable using a maximum posterior probability (MAP) decoding. In a preferred embodiment, the GLDPC code includes a codeword length of substantially 4096, an information word length of substantially 3201, a lower-bound on minimum distance of substantially greater than or equal to 16, a code rate of substantially 0.78 and the RM component code includes an order of substantially 4 and an r parameter of substantially 6. | 08-06-2009 |
| 20090259912 | LDPC CODES AND STOCHASTIC DECODING FOR OPTICAL TRANSMISSION - A method for error correction and a decoder using low density parity check (LDPC) codes includes initializing extrinsic probability information between variable nodes and check nodes in a bipartite graph including generating a Bernoulli sequence according to a probability of a bit having a value one. Parity checking is performed in accordance with a parity check equation. If the parity check equation is not satisfied, then extrinsic information is updated in check nodes from variable nodes using a parity node update logic circuit in a first half iteration, extrinsic information is updated in variable nodes from check nodes using a variable node update logic circuit in a second half iteration, and the variable nodes are updated with a probability based upon the extrinsic information passed between check nodes and variable nodes wherein the probability represents a likelihood that an ith bit is a one. Information bits are passed when the parity check equation is satisfied or a predetermined number of iterations has been reached. | 10-15-2009 |
| 20090282314 | MULTIDIMENSIONAL TURBO PRODUCT CODES AND GENERALIZED LOW-DENSITY PARITY-CHECK CODES WITH COMPONENT REED-SOLOMON CODES FOR OPTICAL TRANSMISSION - A transmitter, a receiver, and corresponding methods are provided. The transmitter includes encoders configured to encode source bit streams from L information sources into bytes of codewords. Each encoder includes different (n, k) multidimensional turbo-product codes of code rate R=k/n, where k is a number of information bytes, and n is code word length. The encoders operate in at least two phases. A first phase involves operating k | 11-12-2009 |
| 20100050048 | MITIGATION OF FIBER NONLINEARITIES IN MULTILEVEL CODED-MODULATION SCHEMES - A receiver and method are provided for mitigation of finer non-linearities in multilevel coded-modulation schemes. The receiver includes a multilevel Bahl-Cocke-Jelinek-Raviv (BCJR) equalizer configured to receive channel samples of an input signal, partially mitigate fiber non-linearities, and provide symbol reliabilities. The receiver further includes a bit probabilities module coupled to the BCJR equalizer configured to calculate soft bit reliabilities from the symbol reliabilities. The receiver also includes one or more low-density parity-check (LDPC) decoders coupled to the bit probabilities module and the BCJR equalizer, configured to receive the soft bit reliabilities and output code words. The one or more LDPC decoders iteratively provide extrinsic soft information feedback to the BCJR equalizer to compensate for the fiber non-linearities. | 02-25-2010 |
| 20100211849 | MULTI-DIMENSIONAL LDPC CODED MODULATION FOR HIGH-SPEED OPTICAL TRANSMISSION SYSTEMS - Arbitrarily high data transmission rates may be achieved by the use of N-dimensional, LDPC-coded modulation. N orthonormal basis functions are employed using coherent reception, resulting in a proportional increase in transmission rate with only a modest increase in bit-error ratio. | 08-19-2010 |
| 20100232804 | METHODS AND SYSTEMS FOR POLARIZATION MULTIPLEXED MULTILEVEL MODULATION FOR OPTICAL COMMUNICATION - Multilevel soft-equalizer detectors, such as a maximum a posteriori probability (MAP) detector, suitable for use in polarization multiplexed optical communications using multilevel modulations and coherent detection are disclosed. Detection systems and methods may consider two symbols transmitted over two orthogonal polarization states as a two-component symbol, which is effective in eliminating the bit error ratio (BER) floor phenomenon introduced by conventional soft equalizers. | 09-16-2010 |
| 20110085624 | CODED POLARIZATION-MULTIPLEXED ITERATIVE POLAR MODULATION - Systems and methods for optical communication that use a transmitter/receiver. The systems and methods include receiving a modulated, encoded input stream. Channel memory is reduced using coarse digital backpropagation and other channel impairments are removed using turbo equalization. Symbols are detected in the input stream that conform to a non-uniform, polar constellation having a Gaussian source distribution to produce a stream of encoded data. The stream of encoded data is decoded with one or more low density parity check (LDPC) decoders. | 04-14-2011 |
