49results about How to "Improve bit error resistance performance" patented technology

This invention relates to earth digital television broadcast coding method in digital information transmission technique field, which comprises the following steps: diving transmission flow into 752 bit set and adding 261 zeros to get 1013 bit for BCH coding and removing front 261 bit to get BCH(762,752); forming one set of BCH(762,752) with certain number to generate matrix of LDPC(7493,3048),LDPC(7493,4572) or LDPC(7493,6096); deleting output 7493 bit front five correction bit to get final 7488 output bit.

The invention provides a streaming media transmission method and system. The streaming media transmission method comprises the steps of, by a transmitting terminal, determining a coding parameter of acurrent frame based on a communication bandwidth of a current network, and performing SVC video coding on video source data based on the coding parameter to obtain video coding frame data; by the transmitting terminal, performing RTP packaging on the video coding frame data to obtain a RTP media package and copying the RTP media package to a media package buffering queue; by the transmitting terminal, judging whether transmission of an FEC error correction package is needed; if so, performing FEC coding on the RTP media package in the media package buffering queue to generate an FEC error correction package and sending the FEC error correction package to a receiving terminal by the transmitting terminal; judging whether a package loss condition occurs based on the received RTP media package; and if so, performing lost package recovery on the lost RTP media package based on the FEC error correction package which corresponds to the lost RTP media package. The system provides execution modules for the method. By adoption of the invention, the risk that the subsequent video frame cannot be decoded caused by reference frame data loss can be reduced, and a video playing fluency is improved.

The invention relates to a fiber channel sectionalized cyclic redundancy check (CRC) method for longitudinal protection. The method comprises that: when data is transmitted, a transmitter divides data information to be transmitted into a plurality of data sections, wherein a CRC code with a bit length equal to that of an information code is appended in each data section; and after receiving the data, a receiver performs conversion check on each data section according to the CRC code, discards data sections with errors when detecting the errors, and continues using data without any error. By the sectionalized CRC method, the CRC code and the information code have the equal bit length, so error codes of any form can be detected and an error detection rate is 100 percent. The transmission can be ensured to be absolutely reliable, so longitudinal fiber distance protection and remote tripping protection can act after a frame of signal is received, and the acting speed of the protection is further increased. Simultaneously, due to the adoption of the sectionalized CRC method, when a certain data section has the errors, the usage of the other data sections is not influenced, so the error resilience of a fiber channel can be greatly improved, and the acting speed of the protection can be increased.

The invention relates to a short-wave communication system based on fountain codes and single carrier frequency domain equalization and a transmission method thereof, and belongs to the technical field related to wireless communication systems, communication signal processing and channel encoding and decoding. Fountain codes are employed in the short-wave data transmission system, and source encoding-channel encoding-modulation combined optimized technology is used, thereby effectively shortening the file transmission time delay in short-wave unidirectional non-feedback channels, enhancing the reliability of a communication system under severe channel environment, improving file transmission efficiency, and effectively ensuring data reliability. Single carrier frequency domain equalization technology based on time-frequency mixed channel estimation is employed to greatly reduce the complexity of a receiver of a single carrier system, and greatly increase the capability of the system to resist frequency domain selectivity fading due caused by multipath transmission of short-wave channels.

A parameter channel error code resisting method of vocoder line spectrum includes carrying out odd-even calibration on parameter and writing calibration bit into most non-important parameter bit of vocoder at coding end, picking light voiced sound parameters and integrating said parameters with maximum post verification probability algorithm to carry out recovery estimation for raising parameter recovery accuracy by line spectrum then picking line spectrum to make relevant odd-even calibration on parameters at decoding end.

The invention discloses a coding method that consists of: obtaining input information; filling information is arranged at the tail of the input information; encode the input information that is provided with filling information according to the matrix generated by the LDPC code so as to obtain corresponding code word. The invention also provides a decoding method. Correspondingly, the invention provides an encoder and a decoder. The invention can obtain higher coding benefits, improve the anti error code capacity of the system.

The invention discloses a totally blind recognition method for a coding parameter of a convolutional code, which mainly solves the problems of incapability of realizing totally blind recognition and high calculation complexity existing in the prior art. The technical scheme provided by the invention is that: (1) the code length n, the input information bit length k and the register length m are solved according to the mutual check relationship between a convolutional code coder and an information code word; (2) when the code rate k / n is 1 / n, two adjacent bits of the code word in the convolutional code bit stream are taken in sequence to construct an analysis matrix C, and fast Walsh-Hadamard transformation is used for the analysis matrix C to solve a generator matrix G; and (3) when the code rate k / n is (n-1) / n, the first to (n+1)th bits of the code word in the convolutional code bit stream are taken to construct an analysis matrix C, and fast Walsh-Hadamard transformation is used for the analysis matrix G to solve a basic check matrix H; and thus, the totally blind recognition for the coding parameter of the convolutional code is finished. According to the totally blind recognition method, the problem of totally blind recognition for the coding parameter of the convolutional code under the conditions of knowing no priori knowledge and containing an error code are solved well, and the operation complexity is simplified; and the totally blind recognition method can be used for multi-cast communication and intelligent communication.

The invention discloses a spacecraft image decomposition and transmission method. In the method, a high-resolution image on a spacecraft is decomposed into a plurality of non-overlapped sub-images containing overall information of the original image; the sub-images are synthesized by using different encoding and encrypting modes and then transmitted; error codes do not have great influence on the overall image during the transmission; and data is distributed to K-class users with different requirements on image quality on ground, so that the images received by different users have different qualities, namely the users of high authority class acquire the images with high qualities, and the users of low authority class acquire the images with low qualities. Certain compression effect can be achieved by the method instead of conventional image compression modes, so the complexity of processing and transmission equipment on the spacecraft is greatly reduced; and meanwhile, the complexity of the ground image processing and restoring equipment is not changed, so the efficiency and the safety of image transmission of the spacecraft are improved and the images with different qualities are distributed as required.

The invention belongs to the technical field of coding parameter identification and discloses a punctured Turbo code blind identification method under an error code condition. Lower triangular transformation is carried out for a matrix at a galois field GF2; compared with a traditional matrix rank-solving method, the punctured Turbo code blind identification method under the error code condition can remove influences from the error codes to the identification of the code length and the interlacing length to a great extent. Confidence coefficient evaluation is carried out for a verification relationship obtained through Hadamard Transform when punctured Turbo code blind identification method is used for identifying the start point of a group and the length of a register, the identification rate of the start point of the group and the length of the register is increased greatly. The provided method of identifying an interlaced mapping relationship has strong anti-error-code performance as identification is carried out after removal of the error code; and the solving method for the interlacing relationship has the characteristics of low complexity and easy implementation.

The invention discloses a coder and decoder method, a coder decoder and electronic equipment of a picture layer and a sharding layer. The coder and decoder method includes: selecting different limitation loop filtering model (CLF) and / or limitation intra-frame predicdion model (CIP) control manner for the following one of three objects: I, different image sequences; II, images in the same image sequence in different time intervals; III, different shardings in the same image according to network transmission states and video content features by an encoder; encoding CIF and / or CIP control zone bits in picture layer parameter sets and sharding layer parameter sets according to the selected CIF and / or CIP control manner; analyzing sharding layer information code stream, and the picture layer parameter sets and / or the sharding layer parameter sets by a decoder according to the obtained CIF and / or CIP control zone bits, using the corresponding CLF and / or CIP control manner to decode images and shardings. Good compromises between code efficiencies and error-code-resistant performances can be obtained through the coder and decoder method, the coder decoder and the electronic equipment of the picture layer and the sharding layer.

The invention discloses a distributed hyperspectral image coding and decoding method based on three-dimensional wavelet transform. After spectrum wave filtering is carried out for a hyperspectral image at the coding end, information transformed by wavelet is divided into two parts of a high frequency part and a low frequency part. The low frequency part and the high frequency part are respectively as a keyframe and a W-Z frame to carry out independent set partitioning in hierarchical trees (SPIHT) coding. A Wyner-Ziv coder improves code-error-resistance property by adopting a Turbo coding mechanism. At the decoding end, low frequency information is used for predicting the high frequency part and side information is formed, and the combined decoding is carried out with the high frequency part. The high and low frequency parts which are carried out spectrum wave filtering are respectively encoded, and lower computation complexity of a coding end is guaranteed. Due to the fact that combined decoding of the low frequency part and the high frequency part is carried out at the decoding end, spectrum relevancy of the hyperspectral image is fully played. Due to the fact that turbo channel coding is adopted, robustness of coding code stream to channel noise is strengthened, and gradability and flexibility are provided.

The invention relates to a network transmission protocol, and discloses a method and a device for receiving and transmitting description of a scene in a rich media TV, which enables a rich media scene code stream to be efficiently transmitted and cut in randomly in a streaming media mode and other streaming media modes, such as audio frequency and video, and the like. The scene is divided into sections, each section generates a scene group, the first scene unit of each scene group can be independently analyzed, and other scene units can be updated in turn. Parameters shared by the scene units in one scene group or a plurality of scene groups are put in a scene parameter group to be loaded by the independent scene unit. The scene unit is directly mapped to a transmitting layer. A time stamp is set for each scene unit on the transmitting layer to specify process time of each scene and be used for carrying out synchronization with other streaming media, such as video frequency, audio frequency, and the like.

The invention belongs to the technical field of wireless communication, and discloses a blind identification method for non-system convolutional code coding parameters under high error codes, which comprises the following steps: arranging convolutional code bit streams into an L * l analysis matrix, and identifying the code length n; constructing an analysis matrix for the convolutional code bit stream according to the code length n, and identifying the information bit length k; constructing an analysis matrix by using the convolutional code bit stream according to the code length n, and identifying a check vector by using a linear constraint relationship with the check vector; for the system convolutional code, traversing the length m of the register, rearranging the check sequence, carrying out convolution operation on the check sequence and an m + 1-dimensional vector space, and carrying out Gaussian transformation to obtain a generation matrix of the system convolutional code and the length m of the register; and for the non-system code, establishing an equation set by utilizing the check matrix, solving the equation set, and screening to obtain an optimal generation matrix anda register length m of the non-system code. The method well overcomes the blind recognition problem of the convolutional code coding parameters under the condition of high error codes, and can be applied to the fields of intelligent communication, communication investigation, communication countermeasure and the like.

The invention provides a video data self-adapting dividing device in an encoder, wherein, the encoder receives channel data; the video data self-adapting dividing device divides M video frames; one or a plurality of video units are obtained after respectively dividing each video frame; each video unit comprises a plurality of macro blocks; the video units are then used for filling data blocks of physical layers, and each physical layer is guaranteed to comprise a plurality of video units. The video data self-adapting dividing device of the invention is combined with the characteristics of physical channels through self-adapting dividing video data units and by full utilization of data dividing method of information sources and meets as possible the requirement that an image strip or a subdivision is filled in a physical data package, thereby video errors are isolated in the image strip or the subdivision under the condition of abnormality of channels, consequently the invention has the advantages of effective avoidance of expansion of image flaws, improvement of image subjective quality and obvious improvement of anti-error capacity of video data.

The invention discloses a method for encoding a wavelet image. The method comprises the following steps of: classifying corresponding wavelet coefficients, which are obtained by wavelet decomposition, of each subband by using a pyramid structure; performing corresponding encoding operation on the classified wavelet coefficients to acquire a compressed code stream of each subband; according to a rate distortion characteristic of the compressed code stream of each subband, optimally allocating a target code rate between the compressed code streams of each subband; and according to the allocatedcode rate of each subband, cutting off the code stream of each subband to acquire the code stream for encoding the wavelet image. The invention also discloses a device for encoding the wavelet image.By the method and the device, the error-code-resisting capability of the code stream acquired by encoding can be enhanced and the code stream is decoded to obtain images of multiple spatial resolutions.

The invention discloses a block verification and acknowledgement-based satellite network TCP (Transmission Control Protocol) performance enhancement method, and relates to a TCP performance enhancement technology in a satellite communication field. According to the block verification and acknowledgement-based satellite network TCP performance enhancement method, the transmission performance of a TCP in a high error code environment is improved on the premise of not obviously increasing the cost of a TCP by utilizing expansion options of the TCP and introducing a new mechanism of data block verification and block acknowledgement based on ideas of combined transmission and block retransmission on the basis of the compatibility of basic mechanisms, such as TCP flow control, error control and congestion control. The method disclosed by the invention has the advantages of standard TCP compatibility, high error code resistance and low information verification cost, and is particularly suitable for a satellite communication system which performs data transmission by utilizing the TCP.

The invention provides a distributed compression sensing-based hyperspectral image compression method. The method comprises the steps of based on correlation of each band spectrum and information entropy of each band spectrum in a hyperspectral image, dividing all bands into a low correlation band group and multiple high correlation band groups, wherein each high correlation band group comprises a reference band and multiple non-reference bands; determining a region of interest and a background region in the reference band; for each non-reference band, performing differential processing on the region of interest and background region in the reference band, so as to acquire corresponding residual images; sequentially compressing residual images and low correlation band images of the region of interest and background region of each high correlation band group and each non-reference band; and sending code streams of all compression codes. According to the method, different distributed compression processing is performed on different bands and different regions, so that important information of the hyperspectral image is fully protected, and the compression rate of the hyperspectral image is improved.

The invention discloses a method for detecting a bit error rate of a channel which comprises: the filling data of an audio and video signal is obtained; the filling data and the prescient filling data are compared and the bit error rate of the current channel is confirmed according to a comparing result. The invention also discloses a device for detecting the bit error rate of the channel; besides, the invention also discloses a method and device for treating an audio and video signal based on the method and the device. The invention can be utilized to confirm the bit error rate of the current channel by calculating the bit error rate of the filling data; thereby being able to adjust the coding parameter of the audio and video signal to be transmitted according to the bit error rate situation of the current channel so as to lead the capacity of anti-bit error rate of the audio and video signal to be improved, thus avoiding the situation of serious mosaics on an image from appearing.

The invention discloses an anti-error method based on cyclic redundancy check and erasure correction coding, which belongs to the technical field of wireless link digital measurement and control communication with random or burst errors. Add the fast cyclic redundancy check to the length of the code stream, and add the error correction supervision code to the cyclic redundancy check code, and then perform fast Vandermonde erasure coding on the bytes of a certain length by column, and finally send the encoded data to the The input channel is transmitted, and the decoding end decodes and restores the original data in a corresponding manner. The method can be applied to fields such as high compression ratio video code streams that are particularly sensitive to channel code errors, important data protection transmitted in wireless channels with high code error rates, and the like. The invention enables the decoding end to quickly and timely discover and correct data that generates bit errors, has the advantages of large coding gain, small delay, and low algorithm complexity, and provides a real-time processing basis for further reducing the impact of bit errors on video image quality.

The invention discloses a CORS (continuously operating reference system) data coding and transmitting method applicable to long-distance communication. The CORS data coding and transmitting method includes steps of receiving data by the aid of Beidou receivers on Beidou CORS vehicles and transmitting the data to CORS service systems; grouping differential data information in the CORS data; respectively coding two groups of information in an anti-interference manner; transmitting the coded data to high-power ultra-short wave radio sets via ultra-short wave interfaces by the aid of industrial control computers; transmitting the data to long-distance receiving-side radio sets by the aid of the high-power ultra-short wave radio sets to completely transmit the data; transmitting the received data to the industrial control computers by the aid of the receiving-side radio sets and decoding the received data by the aid of the industrial control computers; transmitting the decoded CORS data to background servers to completely transmit the CORS data. The CORS data coding and transmitting method has the advantages that CORS differential data are extracted and coded by the aid of the Beidou CORS vehicles and the high-power ultra-short wave radio sets, so that the CORS data can be credibly transmitted over long distances, the bit error rate of CORS data long-distance communication can be reduced, the communication quality can be improved, and the CORS data coding and transmitting method is particularly applicable to conditions where communication facilities are destructed or communication signals are unavailable.

The invention discloses a lossless compression method for a large-format remote sensing image, and belongs to the field of image processing. The method comprises the following steps: dividing a large-format remote sensing image into independent coding regions which are not overlapped with each other; identifying the dynamic range of the pixel of each independent coding area, and determining the quantized bit number of the pixel; calculating a lossless compression parameter of each independent coding region according to the quantization bit number of each independent coding region; and according to the lossless compression parameter of each independent coding region, carrying out lossless compression on the independent coding region until lossless compression of the large-format remote sensing image is completed. According to the invention, a large-format remote sensing image is divided into a plurality of independent coding areas which are not overlapped with one another; the dynamic range of each independent coding area is identified as the local dynamic range of the large-format remote sensing image, the characteristic that the local dynamic range of the large-format remote sensing image is lower than the fixed dynamic range of the camera is effectively used, the overall lossless compression ratio is increased, compression parameters can be adjusted according to the local dynamic range, and lossless compression of the large-format remote sensing image is achieved.

A gradation-inequality protective method of irregular LDPC code to MPEG-2TS includes address protective processing circuit at emitting end of communication system for storing node adding with high irregular LDPC code degree to let MPEG-2TS code stream packet head and adaptive domain map on node with high irregular LDPC code degree , adding protective counter processing circuit at receiving end of communication system for storing MPEG-2TS stream packet head and adaptive domain address to utilize this address to restore normal order of MPEG-2TS code stream.

The invention discloses a totally blind recognition method for a coding parameter of a convolutional code, which mainly solves the problems of incapability of realizing totally blind recognition and high calculation complexity existing in the prior art. The technical scheme provided by the invention is that: (1) the code length n, the input information bit length k and the register length m are solved according to the mutual check relationship between a convolutional code coder and an information code word; (2) when the code rate k / n is 1 / n, two adjacent bits of the code word in the convolutional code bit stream are taken in sequence to construct an analysis matrix C, and fast Walsh-Hadamard transformation is used for the analysis matrix C to solve a generator matrix G; and (3) when the code rate k / n is (n-1) / n, the first to (n+1)th bits of the code word in the convolutional code bit stream are taken to construct an analysis matrix C, and fast Walsh-Hadamard transformation is used for the analysis matrix G to solve a basic check matrix H; and thus, the totally blind recognition for the coding parameter of the convolutional code is finished. According to the totally blind recognition method, the problem of totally blind recognition for the coding parameter of the convolutional code under the conditions of knowing no priori knowledge and containing an error code are solved well, and the operation complexity is simplified; and the totally blind recognition method can be used for multi-cast communication and intelligent communication.

The invention discloses a CORS data coding transmission system applicable to long-distance communication. The system comprises a mobile big dipper CORS vehicle used for receiving data through a big dipper receiver on the vehicle and sending the data to a CORS service system; a CORS service system used for grouping difference data information in CORS data; a coding module used for performing anti-interference coding on high broadcasting frequency information and low broadcasting frequency information; a high-power ultra-shortwave radio station used for receiving the data coded by the CORS service system through an ultra-shortwave interface, sending the coded data to a long distance receiving end radio station, and accomplishing data transmission; and a decoding module used for decoding the code received by the receiving end radio station, sending the decoded CORS data to a background server, and accomplishing transmission of the CORS data. According to the system, by employing the big dipper CORS vehicle and the high-power ultra-shortwave radio station, long-distance credible transmission of the CORS data is realized through extraction and coding of the CORS difference data, the error rate of long-distance communication of the CORS data is reduced, and the communication quality is improved.