100results about How to "High bit rate" patented technology

To perform link adaptation at radio interfaces of an enhanced packet data cellular network the system behavior is simulated for different C / I conditions. Two sets of tables are obtained, each table including upgrade and downgrade thresholds expressed in terms of Block Error Rate (BLER). The tables are specialized for taking into account EGPRS type II hybrid ARQ, Incremental Redundancy (IR). Transmitted blocks are checked for FEC and results are sent to the network that continuously updates BLER. A reliability filter output is used to decide the weight between new and old measurements. IR efficiency is tested for each incoming block and an indicative variable IR_status is filtered. Each threshold of BLER to be used is obtained by linear interpolation between the tabulated threshold without IR and with perfect IR, both weighed with filtered IR_status. Filtered BLER is compared with interpolated thresholds for testing the incoming of a MCS switching condition.

Methods and apparatus for encoding an arbitrary digital message, e.g., a watermark, into a speech signal are provided. In one aspect of the invention, a method of embedding digital information in a speech signal comprises the steps of: (i) generating a spread spectrum signal, wherein the spread spectrum signal is representative of the digital information and further wherein the spread spectrum signal is within a frequency bandwidth corresponding to speech; and (ii) embedding the spread spectrum signal in the speech signal. By making use of spread spectrum technology and speech analysis techniques in the signal generation and embedding operations, respectively, significantly higher bit rates can be embedded into the speech signal without effecting the perceived quality of the recording. The invention also provides methods and apparatus for recovering the digital information embedded in the speech signal.

The invention discloses an all-optical true random number generator, which comprises an all-optical true random number entropy source, wherein the all-optical true random number entropy source injects output light of a continuous laser device I into a two-section semiconductor laser device through a 3dB optical fiber coupler I and a light attenuator, produces a high-speed chaos self-pulse signal and controls the repeated frequency of the chaos self-pulse signal by adjusting the light injection intensity and the frequency detuning amount. Sampling and subsequent processing are not required; the additional problem caused by signal distortion because of sampling in the prior art is solved; the complexity of a system is greatly reduced; a code rate can be tuned in a large range by changing the light injection intensity and the frequency detuning amount; and the code rate is up to Gbps and can be directly compatible with a light network.

The method includes following steps: (1) based on inputted K bits information packet, encoder for low-density parity check code crates code word in NFIR bits LDPC HARQ parent code; the code word includes bit information packet, expanded check bit packet, and remaining check bit packet after deletion; the created code word is sent to HARQ buffer; (2) rearranging bits of code word of LDPC HARQ parent code in HARQ buffer, and keeping sequence of information bits and expanded check bits unchanged, and changing sequence of remaining check bits; (3) selecting bits code word in sequence from rearranged code word of HARQ parent code, i.e. first transmission starts up from first system bits, and then, start position of each transmission follows close to position of ending the previous transmission so as to generate binary sequence of HARQ packet.

A method and apparatus for increasing the capacity of a multiple-input and / or multiple-output system. Each sub-stream of a primary data stream is stratified to produce a processed sub-stream whose strata can be separated out and decoded with an acceptable error rate. A sub-stream can be stratified by dividing it into a plurality of sub-stream-components that are processed to obtain strata, with each stratum representing one of the sub-stream-components. The strata are then combined to obtain the processed sub-stream. Stratifying allows a particular processed sub-stream's strata have different transmit features from each other, such as different bit rates, or different power levels, or both. This reduces the interference for some of the strata of each processed sub-stream since as stratum are separated out and decoded they are no longer interference for the other strata. Thus, allowing for a higher overall bit rate for the processed sub-streams.

The embodiment of the invention discloses a live broadcasting control method and anchor equipment. The method needing to be realized comprises the steps of collecting live broadcasting data, coding and sending to a server; in the process of sending the coded live broadcasting data, acquiring the transmission condition of the live broadcasting data and determining the current usable code rate according to the transmission condition of the live broadcasting data; coding the live broadcasting data depending on the usable code rate and sending to the server. The transmission condition of the live broadcasting data is acquired in the process that the live broadcasting data is coded and sent to the server, the current usable code rate is determined, and then the live broadcasting data is coded by using the current usable code rate, so the transmission smoothness of the live broadcasting data can be ensured, the code rate adaptive to the possibly consistently changed network environment can be obtained in the live broadcasting process, the live broadcasting can be realized by better code rates and a better live broadcasting effect can be obtained.

A method for estimating a Signal to Noise Ratio (SNR) in a received signal including, for a fixed first set of a plurality of samples from the received signal, providing an initial noise estimate, starting with the initial noise estimate, iteratively improving the noise estimate, and estimating SNR based, at least partly, on the fixed first set of samples from the received signal and the noise estimate. Additional related apparatus and methods are also described.

A method and apparatus for encoding a sequence of 32 bit digital data words into a sequence of 33 bit code words in consonance with predetermined minimum zero run length (d) and predetermined maximum zero run length (k) for recording upon a magnetic medium within a magnetic recording channel is disclosed. The method comprises steps of dividing each data word into eight data nibbles, determining whether any data nibble contains all zeros. If no code violation, mapping the eight data nibbles to seven code nibbles and to four bits of a five bit code sub-word and setting a fifth control bit to one. If one or more code violations are present, embedding code violation locations within at least the five bit code sub-word and other code nibbles if necessary and remapping data nibbles ordinarily directed to the code sub-word and nibble locations to code locations otherwise containing the data nibbles determined to be code violations.

The invention provides a quantum key distribution method and system based on orbital angular momentum encoding. An orbital angular momentum entangled state is used as an information encoding carrier at a quantum key encoding transmitting terminal; orbital angular momentum is dynamically modulated through a spatial light modulator, and stable quantum codes are output; received quantum information can be stably and quickly measured at a receiving terminal through the spatial light modulator and a coincidence counting measurer, and by comparing encoding bases and measuring bases on a public channel, quantum bit code information is accurately decoded. The quantum key modulating and demodulating process is highly functionally integrated, information can be conveniently transmitted and received in real time, the system is efficient and stable, tapping behaviors of tappers can be judged in real time by violation verification of a Bell-CHSH inequation, and high-security quantum key distribution is guaranteed.

The invention discloses a device for improving spatially coherent light communication quality based on an adaptive optical technology. The device comprises a telescope module, a wavefront corrector, a light slitting element, coherent receiving module, a wavefront detector, a wavefront processor, a digital-to-analog converter and a high-voltage amplifier. According to the device, the influence of atmospheric turbulences is corrected by use of the adaptive optical technology so that a larger-caliber receiving telescope can be applied to a laser communication receiving end without increasing a wavefront error, and therefore, the receiving power can be improved. An adaptive optical system is capable of effectively improving the degree of phase matching of signal laser and local oscillating laser by compensating random dynamic wavefront aberration caused by the atmospheric turbulences and the inherent static wavefront aberration of the system, and therefore, the frequency mixing efficiency is improved, and finally, the purposes of increasing the signal to noise ratio and reducing the bit error rate are achieved.

Embodiments of decoders supporting multiple code rates and code lengths for data storage systems are disclosed. The decoders can provide for flexible and scalable decoding, particularly when quasi-cyclic low-density parity-check code (QC-LDPC) decoding is used. The decoder can be scaled in size based on, for example, the desired decoding throughput and / or computational cycle duration. In one embodiment, a rotate-left / right shifter is configured to support data having processing units of one of multiple matrix sizes and independently shift portions of the data. In another embodiment, one or more decoding modules are configured to share with one or more other decoding modules an output value from a layer decoding operation. This sharing can facilitate parallel decoding of data by the decoding modules. As a result, decoding speed, efficiency, and system performance can be improved.

The invention relates to an LDPC (Low Density Parity Code)-based method for encoding and decoding two dimensional bar codes, comprising the following steps of: obtaining input information according to encoding type process of the input binary data information; carrying out lengthening compression or fixed-length compression on the input information; calculating an information length required for storing according to a compressed result, obtaining the information to be encoded according to the encoding type and the compression type; carrying out LDPC encoding compression on the information to be encoded; integrating the compressed result and the version information to obtain the compressed information; and setting a flag bit and generating a two dimensional bar code image. The encoding method has large information capacity and strong error correction capability; the aspect ratio can be optionally set; and various types of encoding are supported and the locating is easier.

The invention belongs to the field of multi-media communication, and in particular relates to a state machine based dynamic adaptive video transmission code rate switching method. The state machine based dynamic adaptive video transmission code rate switching method comprises the steps that: a server side slices a stored video; each video clip has K code rate grades; a client side calculates the average code rate, the mean square deviation and the average bandwidth of N video clips according to the newly downloaded N video clips; the code rate offset rate and the playing cache of the client side when downloading of the kth video clip is completed are obtained; and, due to different ranges of the playing cache and different ranges of the code rate offset rate, code rate switching is carriedout according to a code rate state switching formula. According to the state machine based dynamic adaptive video transmission code rate switching method disclosed by the invention, the contact between the video code rate and the numerical value change of an influence factor is used as a state transition condition; on the premise that the playing cache and the code rate offset rate are a certainthreshold value, the code rate is switched to the code rate grade that the whole performances of the video quality and the playing fluency are relatively best; and thus, better user viewing experienceis realized.

The present invention discloses a movement compensation time domain filtering method based on interested area. The method adopts a video diving technique for obtaining the interested region ROI. The method adopts the movement technique of interested region ROI for obtaining the movement vector tree of foreground and background. The method adopts a movement estimation technique of boundary determination for obtaining the movement patch of each pixel. The method adopts a boundary transferring technique of interested region for obtaining the boundary of each stage of low-frequency frame. The method adopts a movement compensation time domain filtering technique of interested region ROI for eliminating time domain redundancy. The former video is divided into two independent regions. Each part can be singly processed. The extensible video coding of content based on interested content is realized through the method. When the code rate is lower, the content region which is interested to the people can be allocated with more code rate. The content of foreground area is clearer for obtaining a better viewing effect.

The invention discloses a wireless intelligent monitoring system and method for a photovoltaic power station. The wireless intelligent monitoring system for the photovoltaic power station comprises a server layer, a gateway layer, a repeater layer and a monitoring module layer, wherein the server layer is the top layer; the monitoring module layer is the bottom layer; bidirectional communication is performed between each two adjacent layers; the server layer consists of multiple servers; the gateway layer consists of multiple gateways; the repeater layer consists of multiple repeater modules; the wireless intelligent monitoring system is characterized in that the monitoring module layer consists of a1-am grouping sequences, wherein m is less than or equal to 65536; each grouping sequence is divided into b1-bm groups, wherein n is a natural number less than or equal to 255; each group consists of i intelligent monitoring modules, wherein i is a natural number less than or equal to 183; each repeater performs wireless communication with all the intelligent monitoring modules in each grouping sequence; the repeaters and the gateways are in wireless communication; and the intelligent monitoring modules are used for detecting information of photovoltaic modules, and perform wireless communication with the repeaters. According to the wireless intelligent monitoring system and method for the photovoltaic power station, the electric energy utilization rate of the photovoltaic power station can be improved, and the wireless intelligent monitoring system and method are wide in application prospects.

The invention relates to a system for generating unpredictable pseudorandom numbers in a chaotic manner, comprising discrete chaotic map processing means and an XOR gate for generating unpredictable pseudorandom numbers. The method is based on introducing a high degree of entropy in the system by cyclically shifting chaotic maps to the right.

A portable electronic device comprises a first wireless interface and a second wireless interface. The first wireless interface is controlled to perform a control signaling with a further device over the first wireless interface. The second wireless interface is selectively activated to transmit data traffic to the further device and / or to receive the data traffic from the further device over the second wireless interface. The first wireless interface is maintained in an activated state to control the data traffic over the second wireless interface by the control signaling over the first wireless interface while the second wireless interface is activated.

A rate 7 / 8 MTR code encoding / decoding method and apparatus. The encoding method includes: generating a rate-7 / 8 MTR code for inputting 7-bit data and outputting a predetermined 8-bit codeword; checking whether codewords satisfy a predetermined constraint condition by connecting the 8-bit codeword and a subsequent 8-bit codeword; and if the codewords do not violate the constraint condition, not converting the codewords. The decoding method includes: checking whether the codewords satisfy a predetermined MTR constraint condition by connecting a current 8-bit codeword c(k) and a subsequent 8-bit codeword c(k+1); if the codewords violate the constraint condition, converting the codewords, and if the codewords do not violate the constraint condition, not converting the codewords; and decoding each converted 8-bit codeword into 7-bit data using a predetermined MTR code. Data is reliably reproduced with high write density, and large amounts of data are stored in and reproduced from a magnetic recording information storage medium.

The invention provides a data checking and correcting method for correcting fixed errors, comprising the following steps of: detecting error image samples to obtain positions and types of the fixed errors; generating a pseudo information sequence; generating a characteristic sequence by an encoder according to the error image samples and the pseudo information sequence; encoding data to generate code words; recovering the characteristic sequence and recovering the corresponding characteristic sequence by a decoder according to redundant data of the output code words; and decoding the data to recover an original information sequence. According to the invention, the complexity and an encoding / decoding time delay are very low when the fixed errors of a bit are corrected by the method provided by the invention; particularly, the lower encoding / decoding time delay can be obtained when a parallel encoding / decoding strategy is utilized; with the adoption of the data checking and correcting method provided by the invention, the errors in a phase change random access memory and the like can be detected; and meanwhile, the method can be used for an application scene with the low time relay, so that the practical value of the method is very great. Meanwhile, a code length can be subjected to self-adaptive adjustment according to an actually needed error rate, so as to obtain the optimal encoding efficiency.

The present invention relates to coding method and coding device that allow Rate-Compatible LDPC (low-density parity-check) codes to have favorable BER performance both with a low code rate and with a high code rate. In coding of LDPC codes that have plural code rates and whose all parity check matrices are composed of plural cyclic matrices, a coder 121 performs the coding in such a way that 1<w0 and w1<w0 are satisfied when the maximum column weight of the cyclic matrices in the check matrix of a certain code whose code rate is not the minimum value among the LDPC codes is defined as w0 and the maximum column weight of the cyclic matrices in the check matrix of a code having a code rate lower than that of the certain code is defined as w1.

The invention discloses an M-ary quadrature amplitude modulation (MQAM)-mode-based physical-layer network coding wireless communication method, and relates to the field of wireless communication. The problem of low system performance caused by three timeslots and four timeslots required by the conventional transmission mode in a two-way relaying channel is solved. The method specifically comprises the following steps of: performing MQAM on the coded bit information S1 and S2 of users N1 and N2 to obtain modulated signals s1(t) and s2(t), simultaneously transmitting the signals s1(t) and s2(t) to a relay node NR, directly adding the signals s1(t) and s2(t) by using the relay node NR to obtain a sum signal rR(t), judging the rR(t), and further mapping a judgment result into the network coding information SR of the S1 and the S2; and performing MQAM on the SR again by using the relay node NR, broadcasting the modulated signal sR(t) to the users N1 and N2, demodulating the received sR(t) by the N1 and the N2 respectively, and performing by-the-bit XOR operation on the obtained network coding information SR and transmitted information stored in a local cache of one user to obtain the bit information of the other user, so that an information exchange process is implemented. The method is applied to the wireless communication.

The invention relates to the field of quantum secret communication. The invention discloses a high-speed local oscillator continuous variable quantum key distribution system and method. The system comprises an Alice terminal and a Bob terminal, wherein the Alice end is connected with the Bob end through an optical fiber channel, the Alice end comprises a first continuous laser module, an optical beam splitter, a quantum key modulation module, an optical attenuator, an optical frequency shift module and an optical beam combiner; and the Bob end comprises a second continuous laser module, an optical coupler, a balance detection module, an analog-to-digital conversion module, a digital signal processing module and a post-processing module. According to the invention, low-noise coherent detection of quantum signal light and high saturation of classic reference light can be flexibly realized, the system is simple, the cost is low, the repetition frequency and the safety code rate of the CVQKD system are greatly improved, and the practical process of the high-speed CVQKD system is further promoted.

A method and apparatus for data coding for high-density recording channels exhibiting low frequency contents is disclosed. Coding is used that satisfies both Running Digital Sum (RDS) and Maximum Transition Run (MTR) properties, which are desirable for achieving high-density recording for recording channels exhibiting low frequency components such as perpendicular magnetic recording channel.

The invention relates to a short wave speed change communication system and a multipath estimation and separation method used by the short wave speed change communication system. The short wave speed change communication system comprises a communication terminal A and a communication terminal B which communicate through a short wave channel, wherein the communication terminal A comprises a modulator A and a demodulator A, and the communication terminal B comprises a modulator B, a demodulator B and a multipath estimation and separation module; the multipath estimation and separation module is connected with the modulator B and used for calculating a code element period value required in the multipath separation, sending the code element period value into the modulator B, and finally transmitting the code element period value to the communication terminal A through the short wave channel; and the demodulator B comprises an analog-digital converter, the analog-digital converter is connected with a shock filter, the shock filter is connected with a detection judgment module, and the detection judgment module is connected with a bit synchronization module which is used for outputting an information sequence. According to the short wave speed change communication system and a multipath estimation and separation method used by the short wave speed change communication system, the multipath interference can be separated without complex channel equalization, the transmission efficiency and the demodulation performance are improved, and the cost and the complexity for realizing communication system hardware are reduced.

The invention discloses an error correction method by using a quasi-cyclic LDPC code based on a Latin square, mainly solving a problem that in the prior art a simple method of finding a Latin square totally satisfying a row column constraint relation is lacked. The method comprises the following steps: (1) searching a position set Psi of elements which are free in value selection in a second row of the Latin square; (2) constructing the second row of the Latin square; (3) constructing a whole Latin square W; (4) generating a verification matrix H of a quasi-cyclic LDPC code; (5) obtaining a generation matrix G according to the verification matrix H; (6) at a sending terminal, coding information with the generation matrix G and sending the information to a channel; (7) at a receiving terminal, carrying out decoding according to the verification matrix H, and recovering information from noise. Simulation shows that, error correction performance of constructed quasi-cyclic LDPC code based on the Latin square is excellent, and the method can be used for carrying out error correction in a communication or digital storage system needing high reliability.

A virtual concatenation method for optical channels in WDM networks. In transmission, the method includes providing for a plurality of frames, each frame including a byte reserved for a concatenation flag; writing the same predefined value in the concatenation byte of n frames (n=1, 2, 3, . . . ); and transmitting the n frames via n respective channels (λ1, λ2, . . . λn). In reception, it includes receiving the first reference frame at one instant; reading the concatenation byte value of the reference frame; receiving the remaining signal frames after a respective determined time; reading the value of the concatenation byte of the remaining signal frames; and identifying and aligning all the signal frames with the same concatenation byte value compensating the reception times.

This invention discloses a bit-stuffing method for crosstalk avoidance in high-speed buses, which comprises the steps of inputting a plurality of data bit streams in parallel to a data input buffer; the data input buffer sequentially inputting data bits of the data bit streams to a bit-switching unit, and the bit-switching unit switching the data bits to generate bit-switched data; parallelly inputting the bit-switched data to a bit-stuffing encoding unit; the bit-stuffing encoding unit performing bit-stuffing encoding on the bit-switched data to generate encoded data bits and inputting the encoded data bits to an encoded data buffer; and the encoded data buffer outputting the encoded data to a high-speed bus. The encoded data bits passed through the high-speed bus are decoded using a bit-removing method to recover the data bit streams.

The present invention discloses an optimized coding method for an omnidirectional video, computer readable storage medium and computer device to solve the technical problem that the video quality cannot be guaranteed under a low code rate in the prior art. The method includes: obtaining attribute information of each coding unit of an omnidirectional video file, wherein each coding unit is a storage and coding unit of the omnidirectional video file; determining a coding mode corresponding to each coding unit according to the attribute information of each coding unit; and coding each coding unit according to the coding mode corresponding to each coding unit.