35 results about "Successive cancellation list" patented technology

The invention discloses a polarization code and multi-bit even parity check code cascaded error correction coding method. The method comprises the steps: a transmitting end encoder utilizes a multi-bit even parity check code as an outer code, and utilizes a polarization code as an inner code; a receiving end decoder decodes by utilizing a modified successive cancellation list (SCL) decoding algorithm. On the aspect of error correction performance, comparing with the prior art utilizing middle-short code length non-cascaded polarization codes of the SCL decoding algorithm, the polarization code and multi-bit even parity check code cascaded error correction coding method has the advantages that frame error rate performance of a system can be remarkably improved, and a maximum likelihood bound (ML Bound), which cannot be broken through by the SCL decoding algorithm, can be remarkably broken through. On the aspect of engineering realization, according to the polarization code and multi-bit even parity check code cascaded error correction coding method, the outer code utilizes the multi-bit even parity check code, which is simple to code; the modified SCL decoding algorithm is utilized to decode, bit decision and even parity check are combined to be carried out in a decoding process, and compared with the original SCL decoding algorithm, the method provided by the invention does not increase the decoding complexity, and facilitates the engineering realization.

Various embodiments are described of a system and method for improved SCL decoder operation. In particular, various embodiments are described which improve the efficiency of the buffer management based on updated path metric statistics. In some embodiments, the SCL decoder may perform selective replacement to limit the extent of LLR updates per row only to the statistics that have changed since the previous update cycle. In some embodiments, the SCL decoder may perform deferred updates, which may involves in-place calculation of both û_φ=0 and û_φ=1 bit estimate (LLR) updates based on the row from which the updated row will be derived.

The invention discloses a Polar code efficient adaptive decoding method based on Gaussian structure. Gaussian judgment is introduced based on the Gaussian structure to carry on path splitting and an effective adaptive decoding algorithm is combined. The method calculates the posteriori probability of each information bit by using the Gaussian structure under a Gaussian channel, and uses the posteriori probability as the decoding reliability of each information bit, and applies the decoding reliability of each information bit to a successive cancellation list (SCL) decoding. If the decoding (decoded as 0 or 1) reliability of a current bit is greater than the reliability of correct decoding, decoding is directly performed or if it is not satisfied, the path splitting is maintained. Decoding is performed by obtaining all effective paths of the current bit after the path splitting based on bit reliability in combination with the effective adaptive decoding algorithm. Numerical simulations show that under the same conditions, the method has lower complexity in the case of maintaining the same performance.

The invention discloses a polarization code decoding method based on a bit flipping serial elimination list algorithm, and solves the problem that an existing SCL (Successive Cancellation List) algorithm has higher time complexity. The method comprises the following steps: step (1), receiving a sequence to be decoded by a communication terminal; step (2), performing SC (Successive Cancellation) decoding on the received sequence to be decoded; step (3), judging whether an SC decoded sequence passes CRC (Cyclic Redundancy Check); step (4), initializing the list width and the number of bit flipping; step (5), selecting a judgment error position set; step (6), selecting one element from the judgment error position set; step (7), decoding by using the bit flipping serial elimination list algorithm; step (8), judging whether elements in the judgment error position set are all selected or not; step (9), the decoding is successful; and step (10), the decoding fails. According to the polarization code decoding method based on the bit flipping serial elimination list algorithm provided by the invention, the SC decoding is carried out firstly, and when the decoding fails, bit flipping and list decoding are combined for re-decoding, thus the decoding performance is improved, and the time complexity of a decoding algorithm is reduced.

The present invention discloses a polar code-repeat code cascade error correction coding method. At a transmit end, the repeat code is used as an outside code, and the polar code is used as an inside code; and a decoder of a receive end uses a correction successive cancellation list (SCL) decoding algorithm to decode. In terms of correction performance, the frame error rate performance of the coding method provided in the present invention is highly stronger than the polar code frame error rate performance of the SCL decoding algorithm or a cyclical redundancy check (CRC)-aided SCL decoding algorithm, and the frame error rate far exceeds the unsurpassed maximum likelihood limit of the SCL decoding algorithm. In terms of engineering implementation, the outside code uses the repeat code, the storage complexity of the outside code coder is very low, the coding is simple, the correction SCL decoding algorithm is adopted for decoding, bit determining of the inside code-polar code and bit determining of the outside code-repeat code are performed jointly, and the decoding complexity is not increased compared with that of the original SCL decoding algorithm and the CRC-aided SCL decoding algorithm, so that the engineering is easy to implement.

The present invention provides a serial offset list bit flip decoding method for a polarization code, which comprises the following steps: a first step of constructing a bit flip index set; a second step of decoding the received signal formula with a CRC-SCL decoder; and a third step of performing SCLF decoding. The serial offset list bit flip (Successive cancellation list flip, SCLF) decoding method for THE polarization code proposed by the present invention is an improved method for the existing SCF and CRC-SCL decoding methods, the SCLF method introduces the concept of bit flipping into theCRC-SCL decoder, thereby further improving the performance of the CRC-SCL decoder. That is, the CRC-SCL decoder can still take remedial measures after finding a decoding failure, so that the currentdecoding is successful.

The invention discloses a successive cancellation list polarization code decoding algorithm with effective low complexity based on random binary data flows and a decoding structural frame thereof. The algorithm comprises the steps of converting received vectors to be decoded into corresponding input probability values through a channel message scaling algorithm; generating corresponding random binary data flows from the computed input probability values, and respectively inputting the data flows into two basic disk-type decoding frames; obtaining the conditional probability values of decoding through computing the data flows by the mixed node of the two basic disk-type decoding frames; working out the conditional probability random data flows of four paths by a phase inverter; obtaining the final judgment of the path probabilities through allowing the four condition probabilities to pass through an AND gate; through the computation of a feedback module, integrating signals, feeding back into the basic disk-type frames, allowing the data flows to pass through the basic disk-type decoding frames for the second time, and thereby obtaining the conditional probability values; and obtaining the optimal path decoding result. According to the algorithm provided by the invention, the complexity of the system is reduced, and meanwhile the random data flow decoding performance is improved.

The invention discloses a high-performance polar code decoding algorithm. When polar code decoding is completed on the basis of standard successive cancellation list (SCL), decoding results are directly output if decoding is correct; and if decoding fails, a bit-flip mechanism is started. Firstly, by means of calculated flip metrics of various information subchannels, position indexes of the various information subchannels are arranged according to the flip metrics from large to small, and the first T position indexes are selected and stored into a flip list; and then T times of new decoding attempts are started, one information position (starting from the information position with the largest flip measurement value) in the flip list is selected every time, and when SCL decoding is conducted at the selected information position, decoding bits currently obtained by the standard SCL decoding algorithm in all paths are all flipped to attempt to recover a correct decoding path to a candidate path. According to the algorithm, in a high signal to noise ratio, the polar code decoding performance can be greatly improved while the decoding complexity is not increased.

A method of low complexity SCL decoding for polar codes is disclosed. The method comprises receiving a codeword vector generated using polar encoding, and sequentially decoding multiple bits included in a source vector from the received codeword vector based on the successive cancellation list (SCL) decoding, wherein the decoding is configured not to perform a comparison of reliability between candidate decoding paths for at least one partial bit among information bits included in the source vector, but to determine value of the partial bits based on a reliability of the corresponding bit. Therefore, it is possible to have a complexity of about 57% while having a performance degradation of about 0.03 dB or less, that is approximately the same as that of the conventional art.

The invention discloses a piecewise polar code encoding/decoding method based on RC-SSCL, and belongs to the field of the communication channel encoding/decoding, and mainly relates to a polar code decoding method based on CRC-SSCL (CRC aided Simplified Successive Cancellation List), and a piecewise encoding/decoding algorithm based on the CRC-SSCL decoding algorithm, wherein the piecewise encoding/decoding algorithm is proposed for further reducing the storage unit, the computation complexity and the decoding delay of the CRC-SSCL. For further reducing the computation complexity and the pathstorage unit of the CRC-SSCL decoding algorithm, a new piecewise principle suitable for CRC-SSCL algorithm is proposed for an information sequence based on the thought of the literature [3]; the CRC is added at each section of information sequence to perform checking, a path is selected for pruning by using the CRC after completely decoding a section of information sequence every time in the decoding process. Therefore, the Multi-CRC SSCL can further reduce the complexity and the storage unit in comparison with the SSCL decoding algorithm proposed by the literature [2]. And meanwhile, the invention further discloses a Multi-CRC ADSSCL algorithm for self-adaptively adjusting the list L size on this basis.

An apparatus and a method. The apparatus includes a receiver to receive a polar codeword of length m^j; a processor configured to determine a decoding node tree structure with m^j leaf nodes for the received codeword, and receive i indicating a level at which parallelism of order m is applied to the decoding node tree structure, wherein i indicates levels of the decoding node tree structure, and wherein the m^j leaf nodes are at level j; and m successive cancellation list decoders (SCLDs) applied to each child node of each node in the decoding node tree structure at level i−1, wherein each of the m SCLDs executes in parallel to determine log likelihood ratios (LLRs) for a codeword of length m^j−i, and wherein each of the m SCLDs uses LLRs of an associated parent node without using a hard decision or a soft reliability estimate of any other node of the other m SCLDs.

The invention provides a low-time-delay polar code decoder combined with deep learning, and particularly, compared with a simplified Successive cancellation list (SSCL) decoder, the low-time-delay polar code decoder has the advantage that the number of calculation times is smaller. The decoder comprises five modules, namely a normal SCL calculation module, a Rate-0 calculation module, a Rep calculation module, a Rate-1 calculation module, and a DNN calculation module of a common node. The SSCL decoder combined with the deep neural network retains the original low decoding delay characteristicof Rate-0, Rate-1 and Rep nodes, a deep neural network is used for decoding common nodes to reduce the decoding delay, and finally the purpose of reducing the overall decoding delay is achieved. Experimental calculation shows that when the code length is 64 and the code rate is 1/2, the decoding delay is reduced by about 27% compared with the decoding delay of the SSCL.

The disclosure is related to a pre-5^th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4^th-Generation (4G) communication system such as Long Term Evolution (LTE).

A method for operating a first device in a wireless communication system includes receiving information bits and distributed cyclic redundancy check (CRC) bits from a second device, and decoding the information bits and the distributed CRC bits, wherein the information bits and the distributed CRC bits are decoded by using a successive cancellation list decoding scheme that uses a parity check matrix determined based on a linear combination of rows of a predetermined parity check matrix, or by using a successive cancellation flip decoding scheme that uses the distributed CRC bits.

The invention discloses an information encoding and decoding methods and devices and an information processing system, and relates to the field of mobile communications. The information encoding device divides an information symbol sequence into m sections of equal-length sub-sequences, m being a positive integer power of 2, performs CRC (Cyclic Redundancy Check) operation on the ith section of sub-sequence Di by using a corresponding CRC generator polynomial to obtain a corresponding CRC check code CCi, i being more than or equal to 1 and less than or equal to m, calculates a check code CCDiof Di by using the corresponding CRC check code, performs polarization encoding on a code word [Ti], Ti being equal to [Di|CCDi], and sends a polarization encoding result to a receiving end for decoding. According to the information encoding device, missed detection in a CRC-SCL (Successive Cancellation List) decoding algorithm is avoided by using double CRC check codes without changing the numberL of standby paths, and the decoding performance is improved.

The invention provides a decoding method for a polar code and a decoder. The decoding method comprises the following steps: acquiring to-be-decoded data; performing SCL (Successive Cancellation List)decoding and SC (Successive Cancellation) decoding on the data; obtaining a decoding result of the SC decoding; stopping the SCL decoding under a condition of determining that the decoding result of the SC is correct; and outputting the decoding result of the SC decoding. The decoding method for the polar code, provided by the invention, can perform the SCL decoding and the SC decoding on the to-be-decoded data, output the result of the SC decoding when the decoding result of the SC decoding is determined to be correct, take the decoding result as a final decoding result of the data and stop the SCL decoding on the data, so that the decoding of the polar code reduces a decoding time delay and improves the decoding efficiency on the premise of guaranteeing the decoding accuracy.

The invention discloses a polarized channel coding method for a measurement while drilling transmission system. The method comprises: a channel coding module of an underground instrument first calculates a cyclic redundancy check (CRC) code of transmitted data, adds the CRC code to a specific position of an information bit or a fixed bit, and then codes the transmitted data and the CRC code thereof by adopting a coding method for a Polar code; and a decoding module of a ground instrument performs coding by adopting a CRC-assisted successive cancellation List (CA-SCL) algorithm to restore the underground transmitted data. The method has the advantages that the specific CRC code position is selected by Gaussian approximation, the Polar code is constructed, and a certain coding gain can be obtained at a receiving end after CA-SCL decoding, so that the bit error rate of the measurement while transmitting transmission system is effectively reduced.

A method is performed by an information decoder. The method comprises obtaining (S102) an encoded sequence having been encoded using a polar code. The method comprises successively decoding (S104) theencoded sequence into the successive bits of the decoded sequence. Successively decoding the encoded sequence comprises performing a threshold check (S106) for evaluating a bit uncertainty criterion.Successively decoding the encoded sequence comprises branching (S108) the decoded sequence into two candidate decoded sequences whenever the threshold check fails.