8 results about "Error floor" patented technology

The application provides a joint coding method and device under a relay channel model, a storage medium, and an apparatus. The method adjusts a sending scheme according to the characteristics of a joint coding matrix, increases original bit information, reduces compressed bit information, and reduces the error floor level of the overall system. The decoding and forwarding of the relay node provides the compressed bit information reduced in the sending node, so that the destination node can have more information for decoding, and the performance of the waterfall region of the system is improved. In the case that the total energy of the sending node and the relay node is constant, the optimal adaptive joint coding sending strategy is selected by optimizing different energy allocation conditions. The scheme uses the same joint coding matrix in the sending node, the relay node, and the destination node, does not increase the complexity of coding and decoding, and has the characteristics of low complexity.

The present application provides a coding method and a communication apparatus. A sub-matrix of a core check region of a base graph of LDPC is designed, such that the sub-matrix of the core check region meets certain characteristics, and the minimum cycle length of the base graph corresponding to the core check region can be increased to the maximum value, thereby preventing the problem whereby when a core check sub-matrix of a base graph uses an IRA structure, numerous small-scale trapping sets are present and error floors are likely to occur at a plurality of lifting values. In addition, for the design of a core check sub-matrix, a corresponding coding method is further provided, so as to reduce the coding complexity when the core check sub-matrix provided in the present application is applied to coding.

The present application provides an encoding or decoding method and a communication apparatus. A base matrix applied to LDPC provided in the method is different from a base matrix in an existing solution. Compared with two columns in the base matrix in the existing solution that have a relatively large absolute value of the difference between column weights, in the design of the base matrix provided in the present application, the two columns have more regular column weights. In addition, elements of the two columns in a row region other than a given row region are the same. When the two columns are from a column region of the base matrix that satisfies corresponding characteristics, and the given row region is from a row region of the base matrix that satisfies corresponding characteristics, the base matrix can generally reduce the error floor under the application of different code lengths and code rates in a wireless system, so that the base matrix can be applied to a high-reliability communication scenario.

This disclosure describes techniques regarding improving the decoding performance of a code word, such as an LDPC code word. In an example, the error correction capability of a decoding layer is improved, where the improvement can include lowering the error floor. To this end, high order information is used in the decoding. High order information refers to information used during the decoding of a variable node that has an error, which is not limited to that variable node and the check nodes connected to it, but includes information about variable nodes that also have an error and are connected to the variable node via satisfied check nodes, and about unsatisfied check nodes connected to these variable nodes.

This disclosure relates to techniques related to improving error floor performance of a belief flip (BF) decoder. In some examples, the error floor performance is improved by determining a set of unreliable check nodes (CNs) and using information about the set of unreliable CNs to compute flip energies of variable nodes (VNs). In this way, flip energies can be more accurately computed, thereby reducing the error floor. The set of unreliable CNs can be constructed by applying various criteria, such as criteria related to path length to unsatisfied CNs, degree of VNs in paths to unsatisfied CNs, and / or check sum values. Path length and VN degree can be used as selection criteria to determine which CNs qualify to join the set of unreliable CNs. Check sum values can be used as a trigger condition for constructing and / or using the set of unreliable CNs.

The invention provides a coding or decoding method and a communication device. A basis matrix applied to LDPC (Low Density Parity Check) provided in the method is different from a basis matrix in an existing scheme. Compared with two columns with larger absolute values of the difference value of the column weight in the basis matrix of the existing scheme, the column weight of the two columns is more regular in the design of the basis matrix provided by the invention. In addition, the elements of the two columns in other row areas except the given row area are the same. When the two columns are from the column area, meeting the corresponding characteristics, of the basis matrix and the given row area is from the row area, meeting the corresponding characteristics, of the basis matrix, the basis matrix can generally reduce the error floor under the application of different code lengths and code rates of a wireless system, so that the method can be applied to a high-reliability communication scene.

The invention relates to a local decoding method of a coding modulation system adopting a constant weight former, and belongs to the technical field of information theory and coding. The method comprises the following steps: in a low density parity check (LDPC) coding modulation system adopting a constant weight shaper (CCDM), when decoding of an original minimum sum (MS) algorithm fails, performing double expansion on a connection relation of a Tanner graph based on an LDPC code on a check node UCNs which is not satisfied and a CNs connected with a variable node VNs corresponding to an unreliable bit in a CCDM code word; vNs connected with the CNs are selected through double expansion, values of corresponding positions in the original confidence vectors are locally corrected through candidate VNs, and a candidate input information vector list is generated; and re-decoding the vectors in the list one by one to obtain a decoding output result. According to the method disclosed by the invention, the error platform of the LDPC code in the coding modulation system can be reduced without remarkably increasing the calculation complexity, the error diffusion in the inverse forming process of the system is reduced, and the transmission reliability of the LDPC coding modulation system is improved.

The invention provides a joint coding method, device and equipment under a relay channel model and a storage medium, a sending scheme is adjusted at a sending node according to the characteristics of a joint coding matrix, original bit information is increased, compressed bit information is reduced at the same time, and the error leveling level of a whole system is reduced. And meanwhile, reduced compressed bit information is provided at the sending node by utilizing decoding and forwarding of the relay node, so that the destination node can have more information for decoding, and the waterfall zone performance of the system is improved. Under the condition that the total energy of a sending node and a relay node is fixed, the optimal self-adaptive joint coding sending strategy is selected by optimizing different energy distribution conditions. According to the scheme, the same joint coding matrix is used at the sending node, the relay node and the destination node, the coding and decoding complexity is not increased, and the method has the characteristic of low complexity.