Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided. The interleaving and mapping method comprises: performing first bit interleaving on a parity bits part of the LDPC codeword to obtain interleaved parity bits; splicing an information bit part of the codeword and the interleaved parity bits into a codeword after the first bit interleaving; dividing the codeword after the first bit interleaving into multiple consecutive bit subblocks in a predetermined length, and changing the order of the bit subblocks according to a corresponding permutation order (bit-swapping pattern) to form a codeword after second bit interleaving; dividing the codeword after the second bit interleaving into two parts, and writing the two parts into storage space in a column order respectively and reading the two parts from the storage space in a row order respectively to obtain a codeword after third bit interleaving.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and relevant device. The generated preamble symbol contains: a time-domain symbol with a first three-segment structure; or a time-domain symbol with a second three-segment structure; or a free combination of several time-domain symbols with the first three-segment structure and/or several time-domain symbols with the second three-segment structure arranged in any order.

Abstract: A media content-based adaptive method, device and system for Forward Error Correction (FEC) coding and decoding of a systematic code, and a medium are provided. The method includes: dividing, according to the importance of media content, source data into N types of source data packets according to priorities; generating N types of intermediate codes according to the N types of source data packets and the priorities thereof; setting, according to the N types of intermediate codes, recovery data of N types of source data according to a channel condition, and generating coded symbols of N types of systematic codes; receiving the coded symbols, and arranging and sorting the coded symbols according to decoding requirements; and decoding, according to the number of received coded symbols, intermediate codewords according to different situations, and recovering the corresponding source data packets according to the intermediate codewords.

Abstract: The invention provides an FEC (Forward error correction) mechanism based on media content. The mechanism classifies the media content, and endows it with different importance, and then changes the coding scheme according to the packets belonging to frames of different importance in combination with channel conditions and user experience, to conduct protection according to the importance of corresponding frames. By using the technical scheme of the invention, for the data congestion caused by excessive coding in the current FEC system, the media content is able to be classified and endowed with different importance, and controlled by signaling and indicating bit; different FEC coding strengths is able to be adopted; the duplication-expanding window fountain code with the unequal error protection performance is able to be further adopted, to achieve the maximum guarantee of media content quality and reduce the large amount of data caused by FEC.

Abstract: Provided are a preamble symbol receiving method and a receiving device, characterized in that: the received preamble symbol contains a time-domain symbol which is generated from a single three-segment structure by a transmitting end according to a predefined generation rule, the single three-segment structure containing: a time-domain main body signal, a prefix generated based on the entirety or a portion of the time-domain main body signal, and a postfix or a hyper prefix generated based on the entirety or a portion of the time-domain main body signal. Therefore, using the entirety or a portion of a certain length of a time-domain main body signal as a prefix, it is possible to implement coherent detection, which solves the issues of performance degradation with non-coherent detection and differential decoding failure under complex frequency selective fading channels.

Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided. The interleaving and mapping method comprises: performing first bit interleaving on a parity bits part of the LDPC codeword to obtain interleaved parity bits; splicing an information bit part of the codeword and the interleaved parity bits into a codeword after the first bit interleaving; dividing the codeword after the first bit interleaving into multiple consecutive bit subblocks in a predetermined length, and changing the order of the bit subblocks according to a corresponding permutation order (bit-swapping pattern) to form a codeword after second bit interleaving; dividing the codeword after the second bit interleaving into two parts, and writing the two parts into storage space in a column order respectively and reading the two parts from the storage space in a row order respectively to obtain a codeword after third bit interleaving.

Abstract: A dynamic time window and cache method under the heterogeneous network transmission is provided, including adding Available_Time and Asset_Size attributes of the media content in the signaling or other places for the existing signaling at a MMT, so that the client terminal gets the time when the corresponding media content is available and the size of the media content; at the same time determining the network bandwidth and the network delay of the content from the broadband to the client under the current broadband network by the client; wherein the client terminal calculates the time interval for transmitting a request for caching in advance and the size of a cache window required by the terminal through the available time of the content of a broadband source and the delay of a broadband channel.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and a relevant device, characterized in that the method comprises: generating a cyclic prefix according to a partial time-domain main body signal truncated from a time-domain main body signal; generating a modulation signal based on a portion or the entirety of the partial time-domain main body signal; and generating time-domain symbols based on at least one of the cyclic prefix, the time-domain main body signal and the modulation signal, wherein the preamble symbol contains at least one of the time-domain symbols.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and a relevant device, characterized in that the method comprises: generating a cyclic prefix according to a partial time-domain main body signal truncated from a time-domain main body signal; generating a modulation signal based on a portion or the entirety of the partial time-domain main body signal; and generating time-domain symbols based on at least one of the cyclic prefix, the time-domain main body signal and the modulation signal, wherein the preamble symbol contains at least one of the time-domain symbols.

Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided. The interleaving and mapping method comprises: performing first bit interleaving on a parity bits part of the LDPC codeword to obtain interleaved parity bits; splicing an information bit part of the codeword and the interleaved parity bits into a codeword after the first bit interleaving; dividing the codeword after the first bit interleaving into multiple consecutive bit subblocks in a predetermined length, and changing the order of the bit subblocks according to a corresponding permutation order (bit-swapping pattern) to form a codeword after second bit interleaving; dividing the codeword after the second bit interleaving into two parts, and writing the two parts into storage space in a column order respectively and reading the two parts from the storage space in a row order respectively to obtain a codeword after third bit interleaving.

Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided. The interleaving and mapping method comprises: performing first bit interleaving on a parity bits part of the LDPC codeword to obtain interleaved parity bits; splicing an information bit part of the codeword and the interleaved parity bits into a codeword after the first bit interleaving; dividing the codeword after the first bit interleaving into multiple consecutive bit subblocks in a predetermined length, and changing the order of the bit subblocks according to a corresponding permutation order (bit-swapping pattern) to form a codeword after second bit interleaving; dividing the codeword after the second bit interleaving into two parts, and writing the two parts into storage space in a column order respectively and reading the two parts from the storage space in a row order respectively to obtain a codeword after third bit interleaving.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and a relevant device, characterized in that the method comprises: generating a cyclic prefix according to a partial time-domain main body signal truncated from a time-domain main body signal; generating a modulation signal based on a portion or the entirety of the partial time-domain main body signal; and generating time-domain symbols based on at least one of the cyclic prefix, the time-domain main body signal and the modulation signal, wherein the preamble symbol contains at least one of the time-domain symbols.

Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided.

Abstract: A dynamic time window and cache method under the heterogeneous network transmission is provided, including adding Available_Time and Asset_Size attributes of the media content in the signaling or other places for the existing signaling at a MMT, so that the client terminal gets the time when the corresponding media content is available and the size of the media content; at the same time determining the network bandwidth and the network delay of the content from the broadband to the client under the current broadband network by the client; wherein the client terminal calculates the time interval for transmitting a request for caching in advance and the size of a cache window required by the terminal through the available time of the content of a broadband source and the delay of a broadband channel.

Abstract: The invention provides an FEC (Forward error correction) mechanism based on media content. The mechanism classifies the media content, and endows it with different importance, and then changes the coding scheme according to the packets belonging to frames of different importance in combination with channel conditions and user experience, to conduct protection according to the importance of corresponding frames. By using the technical scheme of the invention, for the data congestion caused by excessive coding in the current FEC system, the media content is able to be classified and endowed with different importance, and controlled by signaling and indicating bit; different FEC coding strengths is able to be adopted; the duplication-expanding window fountain code with the unequal error protection performance is able to be further adopted, to achieve the maximum guarantee of media content quality and reduce the large amount of data caused by FEC.

Abstract: This invention discloses a digital TV broadcast system coordinated with a broadband communication network, an information transmission network in which the broadcast system is applied, a digital TV heterogeneous network architecture, and a client terminal used in each of the above network systems. The various broadcast system architectures of the invention adopt the design concept of heterogeneous network which integrates a broadcast network with other networks, for example, a communication network, the Internet and the like, to form a heterogeneous network architecture coordinating various networks. Meanwhile, the usage in bad conditions are taken into account, and a broadcast TV system which enables uplink transmission by using a broadcast link is designed. The terminal of the invention is a terminal applicable in these heterogeneous network architectures, is capable of receiving signals transmitted from various networks, and can enable flexible receiving and access modes with a series of control means.

Abstract: An interleaving and mapping method and a deinterleaving and demapping method for an LDPC codeword are provided.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and a relevant device, characterized in that the method comprises: generating a cyclic prefix according to a partial time-domain main body signal truncated from a time-domain main body signal; generating a modulation signal based on a portion or the entirety of the partial time-domain main body signal; and generating time-domain symbols based on at least one of the cyclic prefix, the time-domain main body signal and the modulation signal, wherein the preamble symbol contains at least one of the time-domain symbols.

Abstract: Provided are a preamble symbol receiving method and a relevant device, characterized in that: the received preamble symbol contains a time-domain symbol which is generated from a single three-segment structure by a transmitting end according to a predefined generation rule, the single three-segment structure containing: a time-domain main body signal, a prefix generated based on the entirety or a portion of the time-domain main body signal, and a postfix or a hyper prefix generated based on the entirety or a portion of the time-domain main body signal.

Abstract: Provided are a preamble symbol generation method and receiving method, and a relevant frequency-domain symbol generation method and relevant device. The generated preamble symbol contains: a time-domain symbol with a first three-segment structure; or a time-domain symbol with a second three-segment structure; or a free combination of several time-domain symbols with the first three-segment structure and/or several time-domain symbols with the second three-segment structure arranged in any order.