69 results about "Short Code" 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.

A receiver that receives a long pseudonoise (PN) code signal composed of two shorter codes interleaved with one another, includes a correlator unit that correlates the received signal with one or more reference codes corresponding to the two interleaved codes, respectively, and generates correlation signals. The receiver also includes an even code detector coupled to the correlator unit, for detecting from the correlation signals one of the two shorter codes, and an odd code detector coupled to the correlator unit, for detecting from the correlation signals the short code that is not detected by the even detector. A delay unit is coupled to the even and odd code detectors, and delays the even or the odd correlation signals so as to align the correlation signals. The aligned signals are combined and evaluated by a merit function. If the combined signals exceed a threshold value the short codes are determined to be aligned, the phase of each code can be determined, and the phase of the longer code can be determined from the determined phases of the shorter codes. The receiver can detect two short PN codes that have been combined, such as by interleaving the short codes, to create a long PN code. Hence, the receiver can inexpensively detect the two short codes which allows the receiver to detect the long code with high gain.

An interleaved coding method can be used in a transmitter, in which the two or more pseudonoise (PN) codes are interleaved to form a longer interleaved code. The method can be used in a transmitter that includes a first code generator generating a first code of n symbols, and a second code generator generating a second code of m symbols, where n and m can be mutually prime, such as m=n+1. An interleave unit is coupled to the first and second code generators, and interleaves the symbols of the first code with the symbols of the second code to output an interleaved code. The interleaved code has a period longer than either of the constituent PN codes, providing for much increased noise tolerance over using the short codes alone, and can be detected at a much lower hardware and time cost than if using a single PN code of equal length.

According to this invention, encoded data of a target data amount can be generated by one image input operation while both lossless encoding and lossy encoding are adopted. For this purpose, a first encoding unit which generates lossy encoded data, a second encoding unit which generates lossless encoded data, and an attribute determination unit which detects the number of colors in a pixel block to be encoded parallel-process the same pixel block. When the number of colors in the pixel block of interest is equal to or smaller than a predetermined number, an encoding sequence control unit stores lossless encoded data in a first memory. When the number of colors exceeds the predetermined number, the encoding sequence control unit stores encoded data of a shorter code length among lossy encoded data and lossless encoded data in the first memory.

A detector receives a signal and detects from it a long code composed from shorter codes, where the shorter codes are dithered according to a non-repeating dither pattern. The received signal is correlated with a reference code, the correlation sums are ranked, and short codes detected from the ranked sums. Because of a high jamming to signal (J / S) ratio, all the transmitted short codes may not be detected. A dither matching algorithm determines an interval between the detected codes and matches it with a previously stored dither pattern. If there is a strong match, the correlation sums and respective receive times are stored in a hypothesis data structure. If enough subsequent correlation pair have similar matches to exceed a threshold, the match is declared correct and the results are output. The time difference between received and matched pairs can be a measure of a pseudorange between transmitter and receiver.

System and method for decoding variable-length codes. A variable-length decoder includes an address generator and a local memory unit. The local memory stores a variable-length code look-up table. The local memory can be programmed to include a look-up table supporting substantially any decoding algorithm. In one embodiment, a decoder memory unit and a system memory unit are employed together with the local memory to store a codeword look-up table. The shortest codes are stored in local memory, the next shortest in decoder memory, and the longest codes are stored in system memory. A multistage search algorithm is employed to search for the longest codes. The address generator generates the address of the code table to be searched by adding the value of the bits to be searched to a base address.

The invention provides a signaling coding method and a signaling coding system based on BCH code and short LDPC code cascading. The method comprises the following steps: establishing a zero padding group table of the correspondence between the sequences of zero padding groups divided in turn and the positions of the zero padding groups based on a default LDPC code check matrix and establishing a punching group table of the correspondence between the sequences of punching groups divided in turn and the positions of the punching groups based on the default LDPC code check matrix; zero-padding an input signaling after scrambling treatment according to the zero padding group; sequentially calculating the BCH code check bit and the LPDC code check bit corresponding to the signaling after zero padding based on preset BCH code and LPDC code error correction coding parameters; and determining the number of punching bits of the LPDC code check bit based on the preset linear relationship between the code length of the signaling and the number of punching bits, and punching the LDPC code check bit according to the number and according to the punching group table.

The invention discloses a carrier synchronization method based on coding and pilot frequency joint assistance. The method comprises the steps that: first, an LDPC-Hadamard code with a short code length and low code rate is designed, an optimal pilot frequency structure is designed based on a valuation theory, a carried rough synchronization method is designed based on correlation functions and ideas, and the valuation precision can reach a Cramer-Rao bound (CRB); and then soft demodulation and decoding operation are carried out on a roughly synchronized signal, soft modulation is carried out on soft information which is output after decoding, and the fine synchronization of carrier is carried out with the soft modulation signal based on expectation maximum algorithm. Simulation shows that the high-order QAM carrier synchronization method based on coding and pilot frequency joint assistance can greatly improve the carrier synchronization accuracy and scope, reduce the decoding times of a decoder, and work in deep space, a satellite and other communication systems with low signal-to-noise ratio.

Disclosed is a method of compressing data contained in variable length or universal variable length code words to be carried in a digital bitstream. The method includes formatting a first set of code words for data and then constructing a second set of code words containing code words from the first set as well as concatenations of code words from the first set. Code words from the second set are to carry data in compressed form in the digital bitstream. One way in which the concatenation is accomplished includes selecting a code word from said first set of code words and applying it as a prefix to itself and to all of the other words in the first set, thereby constructing the second set. The code word selected from the first set for application as a prefix may be the shortest code word of the first set.

The present invention provides a data lossless remote code updating method and apparatus. The method comprises: S1, a server side sends a ProcessAppInfoMsg frame, the frame transmits a total byte number and a total packet number of a code to a controller, the controller writes the total byte number and the total packet number of the code into a designated position of an SD card for a checking frame to check, and the controller returns the ProcessAppInfoMsg frame; S2, the server side sends the ProcessAppInfoMsg frame, a controller side checks the frame according to a check code of the frame and if the frame is correct, the codes are written into corresponding addresses of the SD card according to a record format of the SD card; S3, the server side sends the ProcessAppInfoMsg frame, the frame is sent after code frames are sent, a 32-bit total checksums of all the codes is recorded in the frame, checking is successfully carried out if a 32-bit total checksum of all the code frames read from the SD card is equal to that of all the codes, or error information is carried by a return frame of the frame and a server is requested to resend the frame; and S4, the server side sends the ProcessAppInfoMsg frame, a user application skips to the position of a bootloader after receiving the frame, and the bootloader completes the code updating operation. The data lossless remote code updating method and apparatus have the advantages of short code updating time and lossless data.

A generator generates a composite code from dithered copies of a reference code to form an optimal stationary dither code. The generator either dithers the length of the reference code to generate a boundary dither code composed of a series varying length short codes, or it dithers the phase of the reference code to generate rotation dither code composed of a series of fixed length short codes that vary in phase. The generator dithers the reference code according to a dither pattern. The composite code is an optimal dither code, having an optimal autocorrelation properties, by generating a dither pattern in which phase vectors for the constituent code are not repeated within the code.

The invention relates to the field of artificial intelligence, in particular to an oil and gas well liquid level intelligent monitoring method and device. Characteristic data in the oil and gas well in the current time period are collected; calculating the abnormal degree of the feature data at each moment; calculating the transmission urgent degree of the feature data; grading the feature data in the current time period, and calculating an adjustment coefficient of the feature data of each grade; constructing an adjustment coefficient sequence of each level of feature data; performing Huffman coding according to the adjustment coefficient sequence of the feature data of each level in the current time period, correcting the duration of the next acquisition time period to obtain a coding result of each time period, and transmitting the coding result; and decoding the coding result to obtain oil and gas well characteristic data, and regulating and controlling oil and gas well parameters according to the abnormal degree of the characteristic data. According to the method, the problem that the abnormal data is not the shortest code value in the traditional Huffman coding is solved by calculating the adjustment coefficient, and the rapid and accurate transmission of the abnormal data can be realized.

The disclosure relates to a method, apparatus, and recording medium for encoding an intra-prediction mode of an image using variable length codes, including: determining an intra prediction mode of a current block; determining an intra prediction mode having smallest mode number among intra prediction modes of encoded adjacent blocks as Most Probable Mode; generating and allocating variable length codes in ascending order from shorter code with higher similarity for directivity with MPM for all intra-prediction modes; and encoding intra prediction mode of current block based on allocated variable length codes, and thereby generates efficient variable length codes in consideration of high correlation in the intra-prediction modes of current block and peripheral blocks even if intra-prediction mode of current block does not match MPM derived with reference to peripheral blocks, and efficiently compressing information on intra-prediction mode of current block using variable length codes, thereby improving intra video encoding performance.

The invention belongs to the technical field of signal processing, and particularly relates to an aperiodic long-code direct sequence spread spectrum signal time delay estimation method and system based on norm fitting, and the method comprises the steps: carrying out the carrier synchronization and timing synchronization of a received signal, and obtaining an aperiodic long-code direct sequence spread spectrum CDMA baseband waveform; modeling the long code direct sequence spread spectrum signal into a short code direct sequence spread spectrum signal containing missing observation, rearranging the baseband waveform into a missing data matrix according to the code element width of the information code, and obtaining an F norm curve of the missing data matrix; setting an equivalent period,representing the missing data matrix as cyclic repeat representation of a cellular matrix, and obtaining a user signal F norm curve square template according to the cellular matrix and the screening matrix; and modeling the multi-user signal F norm curve as cyclic convolution of a template curve, and solving the model by using a least square method to obtain an out-of-step time parameter of each user. According to the method, the time delay estimation of the high-capacity asynchronous NPLCDSSSCDMA system under the non-cooperative receiving condition can be realized, and the operation complexity of the system is effectively reduced while the good estimation precision is ensured.

The invention relates to a Chinese character input method, in particular to a computer type code Chinese character keyboard technology. The computer type code Chinese character keyboard technology has the main characteristics of few code elements, short code strings, no repeated codes, code-character one-to-one correspondence, touch typing, difficulty in forgetting, and high in regularity. The computer type code Chinese character keyboard technology adopts a design principle that basic unit strokes which composite Chinese characters serve as unique coding elements; on the basis of essential attributes, the strokes are divided into three classes, namely horizontal strokes, vertical strokes and slant strokes; on the basis of structural attributes, the strokes are divided into single strokes, composite strokes and crossed strokes; and on the basis of dimension and coupling attributes, the strokes are divided into main strokes, auxiliary strokes and body strokes. Coding is performed according to the natural state of the strokes in a character, Chinese characters can be input on keyboards with various key orders by using a set of codes, and the codes are true universal codes for the Chinese characters.

The present invention discloses the method of inputting Chinese characters via ten digital keys form 0 to 9. The five basic Chinese character strokes of horizontal, vertical, slant, point and bend are designated to the five digital keys from 1 to 5 separately and 1-3 Chinese character radicals are designated to the other fiver digital keys separately. Each Chinese character is input via its radicals and / or basic strokes in at most four codes, and each Chinese character word is input via the first or all codes of the first Chinese character and the first and last codes of the rest Chinese characters. The said input method is intuitive, simple, low in duplication code rate, short code length and suitable for use in cellphone, computer, etc.

The invention provides a QKD post-processing system and method based on a CRC-SCL decoding algorithm, the system comprises a sender and a receiver, the sender comprises an information interaction unit, a parameter estimation unit, an error correction unit and a confidential amplification unit; the receiver comprises an information interaction unit, a parameter estimation unit, an error correction unit and an amplification unit. According to the continuous variable quantum key distribution characteristic, performance characteristics of error correction codes with different code lengths are combined, on the basis of classical multilateral LDPC code multidimensional negotiation, the polarization codes are introduced for cascade decoding, the excellent error correction performance of the polarization codes based on the CRC-SCL decoding algorithm in medium and short code lengths is fully utilized, and finally decoding is completed. According to the method, the data coordination efficiency is improved, the error correction efficiency is guaranteed, the quantum key generation rate of the QKD system is further improved, and the overall performance of the system is guaranteed.

A microcomputer bit addition verifying coded lock comprises the verifying process that a code M with a certain length is set; the code M is segmented: N1, N2, N3, N4...... Ni are set as the lengths of code segments, and meanwhile N1 & lt; N2 & lt; N3 & lt; N4...... & lt; Ni; the code segments at the first bit to the N1th bit of the code are named as M1, the code segments at the first bit to the N2th bit of the code are named as M2, the code segments at the first bit to the N3th bit of the code are named as M3,...... the code segments at the first bit to the Nith bit of the code are named as Mi; the code M1 is input during authentication, the authentication is passed if the input code is correct, if not, the code M2 is input, the authentication is passed if the input code M2 is correct, if not, the code M3 is input,...... till the final code segment Mi is input. The probability of mistakenly inputting code bit addition of a code possessor is very low for short codes, and the probability of mistakenly inputting code bit addition of a codebreaker is very high for long codes.

The invention discloses a polar code fast serial cancellation list decoding algorithm based on bit flipping. According to the algorithm, the decoding rate is increased by adding identification of fourspecial nodes; meanwhile, a critical set is constructed, error propagation caused by previous decoding errors is avoided; a turnover position is judged and determined by respectively calculating loglikelihood ratio (LLR) values of two special nodes, namely an information bit R1 node and a single parity check (SPC) node; when the parity check bit does not meet the requirement, only the information bit corresponding to the most unreliable input LLR needs to be overturned, so that the overturning frequency is reduced, and the complexity is reduced. Simulation results show that when the block error rate is 10 <-5 >, the signal-to-noise ratio of the improved fast SCL decoding algorithm based on bit flipping is improved by 0.09 dB compared with that of an original SCL decoding algorithm basedon bit flipping, so that the improved decoding algorithm provides a reference algorithm under the condition of medium and short code lengths.

The present invention provides a rapid keyboard input method of computer Pinyin codes. The theory of the method is as follows: initials, finals and tones are defined on the key elements of a keyboard; for a fixed final in a Pinyin scheme, the fixed final is inputted by double-clicking the key element belonging to the final, and other initials and finals can be inputted by clicking respective key elements. The method has the following outstanding characteristics of: a simple input rule, straightforwardness, convenient operation, a high input speed, no need to dismantle character patterns, no need to remember, a large code capacity, a short code length and a good word-building effect.

The invention discloses an encoding method of a Turbo code and a decoding method. The encoding method comprises: on the one hand, directly carrying out low-order modulation on externally input information bits x(k), currently outputting information bits, and marking the same as x''(k); sending the information bits x(k) into a first sub-encoder at the same time; firstly receiving the information bits x(k) by the first sub-encoder, and outputting check bits y(k); appending zeroing bits at the tail part of the x(k) at the same time to enable the first sub-encoder to be in a zero state after encoding is completed; marking the x(k) and the zeroing bits as x'(k); using an interleaver to scramble the order of the x'(k), then sending the same to a second sub-encoder, and outputting check bits z(k); directly carrying out high-order modulation on the check bits y(k) and z(k), carrying out combining to form a symbol yz(k), and outputting the same at the same time; and carrying out alternate switching of a multiplexing module mux on the x''(k) and the yz(k), then alternately outputting the x''(k) and the yz(k), and obtaining a data stream Rx(k) with a code rate as 1 / 2. The method achieves gooderror correction capability of the Turbo code under a short code condition; and uses the code rate of 1 / 2 to achieve performance better than that of an existing code rate of 1 / 3. The method is suitable for use in the field of digital communication.

The invention provides a method and device for generating an aperiodic long-code spreading code, equipment and storage medium, and a storage medium. The method comprises the following steps: determining a primitive polynomial and an initial phase of a local short-period spreading code according to a PRN number, a weekly count and an intra-weekly day count of a satellite; generating a period short code according to the primitive polynomial and the initial phase; capturing a burst frame according to the periodic short code, and performing frame synchronization; generating a first m sequence according to the primitive polynomial and the initial phase; processing the m1 sequence to obtain a decoding result of the user address; obtaining a second m sequence according to the primitive polynomial and the decoding result of the user address; and generating a spreading code of the data segment according to the m1 sequence and the m2 sequence. According to the invention, the aperiodic long-code spreading code with the variable initial phase can be generated, and the interference of illegal users is effectively avoided.

The invention provides a coding and decoding method and device based on LDPC cascading. The method comprises the steps: cascading a long code (LDPC code) and a short code (RM code), wherein error bits which are not completely corrected by an inner code LDPC code can be corrected by an outer code RM code, and due to cascaded joint iterative decoding, more error bits can be corrected. Therefore, the cascade code can realize a lower error code platform; Multiple code rates are supported, and when the code length and the code rate of a long code (LDPC code) are fixed, flexible multiple code rates can be supported by using RM codes with different code rates; the implementation complexity is low, the hardware complexity mainly focuses on the encoding and decoding of LDPC codes and RM codes, and the encoding and decoding are relatively simple, so the effects of reducing the error code platform and supporting multiple code rates can be realized under the condition that a small amount of complexity is increased.

Systems, methods, apparatus, and computer program products are provided for facilitating immediate activation of a promotion. One example embodiment may include an apparatus for facilitating immediate activation of a promotion, the apparatus comprising registration circuitry configured to receive promotion component information, the promotion component information comprising one or more products or services and a price, generate a promotion comprising the promotion component information, and assign promotion identification information to the promotion; and activation circuitry configured to receive information provided in a text message, the text message comprising at least the promotion identification information, a command, the text message addressed to a short code, the command indicative of an instruction to perform with regard to the promotion identified by the promotion identification information.

The invention relates to the field of communication security. The invention discloses a cascade decoding method suitable for CV-QKD system data post-processing. The method comprises: by using a mode of combining long-code-length coding and medium-short-code-length coding, firstly performing error correction by using long-code-length coding so that the number of errors can be quickly reduced to a preset threshold value within a small number of iterations; then reducing the length of the error correction code, regrouping all bits, verifying the code words of the groups of the receiving party andthe transmitting party based on a verification function, performing error correction on the code word groups with inconsistent verification results by adopting medium-short code length coding, and finally correcting all errors to finish decoding. According to the method, the advantages of coding technologies with different code lengths are fully combined, and the error correction rate is increased while the error correction success rate is ensured, so that the overall performance of a CV-QKD system is ensured.

The present invention discloses a coding and decoding optimization method suitable for fountain codes with a short code length. The method can effectively improve the fountain code coding efficiency and performances of decodable codes and can reduce the decoding cost in a condition of a short code length. When coding is performed at a sending end, based on a statistical original information grouping sending probability, and approximate and uniform sending of each original information group is taken as a target for coding. When a belief propagation decoding algorithm is employed at a receivingend, the coding and decoding optimization method employs residual available information in a stopping set to design a multi-layer decoding optimization algorithm, the number of layers can be determined as required to achieve compromising of the decoding algorithm and performances. Through design of the coding and decoding algorithm at a transmit-receive end, the coding and decoding optimization method can improve the fountain code coding and decoding efficiency in a condition of the short code length.