97results about How to "Reduce bit error rate" patented technology

An apparatus, system, and method are disclosed for storage space recovery after reaching a read count limit. A read module reads data in a storage division of solid-state storage. A read counter module then increments a read counter corresponding to the storage division. A read counter limit module determines if the read count exceeds a maximum read threshold, and if so, a storage division selection module selects the corresponding storage division for recovery. A data recovery module reads valid data packets from the selected storage division, stores the valid data packets in another storage division of the solid-state storage, and updates a logical index with a new physical address of the valid data.

The invention discloses a polarization compensation implementation method of a continuous variable quantum key distribution system. The polarization compensation implementation method comprises the following detailed steps that: a transmitting end transmits signal light and local oscillator light through one optical fiber by adopting a polarization multiplexing manner, and a receiving end separates the signal light and the local oscillator light by a polarization beam splitter, wherein a polarization feedback control method is divided into two stages, to be specific, in the light splitting detection stage, the receiving end for distribution of continuous variable quantum keys separate a part of local oscillator light out and covers the local oscillator light into a DC feedback voltage signal through a conversion circuit; and in the polarization correction stage, the receiving end controls a dynamic polarization controller by a feedback algorithm according to the DC feedback voltage to finish polarization correction. The brand-new polarization feedback control implementation method of the continuous variable quantum key distribution system, provided by the invention, has the advantages of effectively preventing the polarization state of continuous variable quantum signals from being subjected to environment interference in the optical fiber communication process, improving the system stability and promoting the practicability of the continuous variable quantum keys.

The invention discloses a method for compensating delay difference among cells in a cooperative multi-point transmission system, mainly solving the problems that the traditional method can not naturally combine signals at air interfaces and not fully develop the potential of CoMP. The realization process comprises the following steps: (1) a user calculates out the delay difference among the cellsand delayed sampling points according to CSI-RS; (2) the user calculates out a phase rotation factor according to the delayed sampling points, and the phase rotation factor is fed back to a serving cell which shares the phase rotation factor with a cooperative cell; (3) the cooperative cell compensates the phase rotation of a signal according to the phase rotation factor; (4) the user calculates out the carrier phase deviation factor of the cooperative cell according to the delay difference, and the phase deviation factor is fed back to the serving cell which shares the phase deviation factorwith the cooperative cell; and (5) the cooperative cell compensates the phase deviation of the signal according to the phase deviation factor. The method can naturally combine signals received by theuser at the air interfaces, thereby obtaining extra array gain.

The invention discloses a hydroacoustic communicating method of shallow sea remote level channel, which is characterized by the following: adopting the modulating pattern of continuous phase frequency shift keying (CPFSK) to modulate highest utility rate MSK pattern to solve envelope constant and phase mutation problem; fitting for remote shallow sea level channel; adopting coherent deexpanding pattern for communicating end to realize high-property transmission; displaying good spread-spectrum communication on the multi-path for hydroacoustic channel.

The invention discloses a hybrid automatic retransmission method, which is used for improving transmission reliability and comprises that: a transmitting end performs sub-carrier mapping of a pilot frequency according to a first pilot frequency pattern, performs sub-carrier mapping of data and transmits the mapped pilot frequency and data; after receiving an error receiving identifier, the transmitting end performs the sub-carrier mapping of the pilot frequency according to a second pilot frequency pattern, performs the sub-carrier mapping of the data, transmits the mapped pilot frequency and retransmits the mapped data; a receiving end performs channel estimation and decoding on received data stream according to the first pilot frequency pattern; in case of a decoding failure, the receiving end sends an error receiving identifier to the transmitting end; and the receiving end performs the channel estimation and decoding of the data steam retransmitted by the transmitting end according to the second pilot frequency pattern. The invention also discloses a device for implementing the method.

The invention provides a control method and control system for NAND flash memory data in a solid state disk. Storage space of the solid state disk comprises multiple flash memories, wherein one memory is taken as first storage space, and the rest flash memories are taken as second storage space. The invention is characterized in that the control method comprises the steps that whether to-be-written data is important data is judged, wherein the to-be-written data will be written to a corresponding position in the second storage space if the data is not the important data, and the to-be-written data will be written to a corresponding position in the first storage space and the to-be-written data will be written to the corresponding position in the second storage space if the data is the important data; and whether new to-be-written data exists is judged, wherein the step of judging whether the to-be-written data is the important data will be started if the new to-be-written data exists, and the step will be ended if the new to-be-written data does not exist. The technical scheme provided by the invention has the advantages that a bit error rate of NAND FLASH can be effectively reduced; and data reliability of the storage system can be effectively enhanced.

This invention relates to a coherent receiver and a signal receiving method used in a super-broadband-radio communication system utilizing the ML calculation algorithm to reform local sample signals, so that it can match with the received singles even better. It is tested that the local sample signal got from ML calculation should be the mean value to the received signals in Causs white noise channel, which reduces the error code rate of the received signals effectively, solves the diffusion problem of differential coherent receivers and saves the calculation circuit necessary for RAKE receiving.

A method of auto-I/Q calibration in modulator and demodulator, including DC cancellation, gain imbalance and phase error calibration is provided for implementation in a front-end circuit without the use of baseband processing signal. In modulator auto-I/Q calibration, the gain amplifier, peak detector, DC gain cell and comparator and auto-I/Q calibration control logic form a calibration loop between modulator output and input buffer. The DC test vectors for their corresponding calibrations are applied to modulator to determine I/Q mismatch. In the calibration loop, the peak detector convert the carrier leakage, differential signal power level caused by the I/Q path gain mismatch and by the local quadrature mismatch into DC signal power level. The comparator is used to measure the DC different on peak deter output under different input test vector. According to the comparing result, the auto-I/Q calibration control logic can get a set of appropriate control code to adjust the inphase and quadrature path gain, phase of LO buffer to minimize the resulting mismatch between corresponding carrier signals presented at modulator output. In demodulator auto-I/Q calibration, a baseband signal generated by dividing a reference clock is utilized as test tone to sense which path has less gain between I/Q for gain imbalance calibration. A down-conversion mixer, low pass filter, unity gain buffer and comparator form the phase calibration loop in demodulator. The mixer mixes the I/Q signal to result a DC offset used to determine which path has phase error when there is quadrature mismatch, and then the extra delay generated by delay cell is added on it.

The invention relates to an optical fiber nonlinearity and dispersion effect compensating device with a resonant cavity. The optical fiber nonlinearity and dispersion effect compensating device with the resonant cavity comprises an optical fiber and further comprises a circulator, an optical fiber-waveguide coupler, a silicon waveguide, a waveguide coupler, the resonant cavity and a chirp grating. The optical fiber, the circulator, the optical fiber-waveguide coupler, the silicon waveguide and the chirp grating are connected in sequence. The waveguide coupler is arranged between the silicon waveguide and the resonant cavity. The resonant cavity generates nonlinear phase shift through the nonlinear optical characteristics of the resonant cavity so as to compensate for the nonlinear effect of the optical fiber. The grating period of the chirp grating changes in the axial direction and enables incident light with different wavelengths to be reflected at different positions, so that a large group delay slope is generated, and the dispersion effect of the optical fiber is compensated for. Compared with the prior art, the optical fiber nonlinearity and dispersion effect compensating device with the resonant cavity has the advantages of real-time compensation, a small size, easy expansion and the like.

The invention discloses a method for constructing an LDPC code check matrix. The pairwise inner product among any three column vectors in the check matrix is computed, then, whether six-membered rings exist in the check matrix and the number of the six-membered rings can be determined, and therefore the six-membered rings can be eliminated or the number of the six-membered rings can be limited. According to the method for constructing the LDPC code check matrix, the problem that an existing method for constructing an LDPC code check matrix randomly can not eliminate the six-membered rings or limit the number of the six-membered rings in the check matrix, and the embodiment shows that the method is effective and good in error rate performance.

The invention discloses a communication system of an intrinsic safety high-speed integrated channel for a mine, which is mainly used for the real-time underground and ground information exchange of a coal mine. The communication system comprises a channel ground optical transmitter and receiver and an underground optical transmitter and receiver, wherein the channel ground optical transmitter and receiver respectively comprises a transmitter and a receiver; the transmitter comprises a signal input unit, a signal output processing unit, a signal multiplexing unit, a string absorbing data interface circuit and an optical fiber receiving and transmitting module which are sequentially connected; the receiver comprises a optical fiber receiving and transmitting module, a series-to-parallel data interface circuit, a signal shunting unit, a signal receiving and processing unit and a signal output unit which are sequentially connected; and optical fiber transmission is realized through the optical fiber receiving and transmitting module between the transmitter and the receiver. The invention has the advantages of low transmission cost, high communication efficiency, simultaneously integrated transmission of the video, voice and data information of the coal mine, information sharing, high system reliability, good openness and high interference resisting capacity.

The invention discloses a sub-carrier remaining method for reducing a peak-to-average power ratio and a bit error rate in a combined way. The sub-carrier remaining method is characterized in that a closed mathematical expression is used for providing an optimum wave-shearing threshold and reducing the peak-to-average power ratio by linear operation in a transmitter, thereby operating a wave-shearing noise sequence by a linear mapping function to generate a sending sequence with the low peak-to-average ratio, and furthermore, a simple expression of the optimum wave-shearing threshold required when generating the wave-shearing noise sequence is provided; and a nonlinear distortion counteracting method for reducing a peak value and assistings a subcarrier wave sequence is introduced in a receiver so as to reduce the bit error rate of a system. The sub-carrier remaining method overcomes the defect that the existing method requires complex nonlinear operation to generate the sending sequence with the low peak-to-average power ratio and needs complex software simulation to generate the optimum wave-shearing threshold and the nonlinear distortion, so that the bit error rate is high. By adopting the sub-carrier remaining method, the peak-to-average power ratio can be reduced only by linear operation, and the bit error rate of the system can be reduced obviously, so that the calculation complexity is reduced greatly, and the performance of the system is improved.

The invention discloses a method for self-elimination of inter-subcarrier interference of a differential OFDM (orthogonal frequency division multiplexing) system. In comparison with a primal differential OFDM system, a zero insertion algorithm and a displacement offsetting algorithm are added, wherein the zero insertion algorithm enables adjacent carriers of a subcarrier carrying information to return to zero, so that, the interference of the adjacent carriers on the information carrying carrier is effectively reduced. In a process of transmitting the information to a receiving terminal through a wireless channel, orthogonality cannot be completely formed under influence of Doppler frequency shift caused by carrier synchronous error and movement, and the subcarriers generate mutual interference; and by the displacement offsetting algorithm, the subcarriers carrying the information are amplified, a signal-to-noise ratio of the subcarrier to the adjacent subcarriers is increased, and the adjacent subcarriers are further subtracted, so that the inter-subcarrier interference is effectively eliminated.

The present invention relates to a quantum coder and decoder with phase modulated polarization state and their application method in the quantum secure communication. Four-state quantum coder or decoder is formed from a phase-polarization controller and a ture random generator, and can implement quantum secure communication using "two linear polarization states and two circular polarization states" four-state coded BB84 protocol; and six-state quantum coder or decoder is formed from two phase-polarization controllers and a synchronous trigger, and can implement six-state coded quantum secure communication.

The invention discloses a simultaneous wireless information and power transfer system and method for transmitting signals and energy at the same time, and simultaneously carrying out information interaction with wireless equipment and providing the energy for the wireless equipment. A spread spectrum communication technology is applied to the simultaneous wireless information and power transfer system, spread spectrum and modulation processing can be carried out on a simultaneous wireless information and power transfer signal before wireless transmission and then demodulation and despreading are carried out on the signal in a receiver sub-system, so that an error rate of the whole system can be effectively reduced, and meanwhile, the influence of various interference signals on the simultaneous wireless information and power transfer signal subjected to spread spectrum processing is small, so that the requirements for a signal-to-noise ratio of the system can be reduced by adopting a spread spectrum modulation mode.

The present disclosure discloses methods and devices for an optical signal encoding and decoding. The optical signal encoding method includes: reading N-ary data bit by bit, and encoding the data into electric signal units: encoding each different digit in the N-ary data into a different electric signal unit, where high level duration and low level duration in the electric signal unit are Ti1, Ti2, . . . , and Tij respectively, i, j, and N are natural numbers, and the different electric signal units are separated by delimiters; and combining the electric signal units corresponding to the N-ary data into a drive signal, where the drive signal is used for being output in a light form. Instable flashing of emitted light of a terminal device is overcome effectively, and information transmission reliability is further improved.

The invention relates to the technical field of data bus communication, and particularly relates to a bus system and a data transmission method based on a combination of polling and uniform time slots. The bus system includes a bus, bus adapters and electronic equipment, wherein the bus performs two-way communication with multiple bus adapters, and each of the bus adapters performs two-way or one-way communication with multiple sets of electronic equipment; and the communication between the bus and the bus adapters adopts the combination of polling and uniform time slots. According to the scheme of the invention, a combination of polling and competitive time slots is adopted, burst services can be processed in time through the uniform distribution of the competitive time slots, the mean waiting time can be reduced, the real-time response characteristics of the system can be improved, and meanwhile, by setting the polling time slots, congestion data caused by competitive collisions canbe effectively eliminated, the network congestion rate can be reduced, the system throughput can be guaranteed, and the polling and competitive time slots can be customized.

The invention relates to a satellite cross-layer joint optimal power allocation method based on a non-cooperative game. The method comprises the following steps: counting real-time information of each user on a synchronous broadband satellite physical layer; considering a satellite as a power limited system and modeling a power allocation problem as a multi-user static non-cooperative game model according to the QoS (Quality of Service) needs of different services; allocating power for the different services according to solutions and adopting corresponding encoding modes on an application layer aiming at the different services; repeating the steps at regular intervals. According to the cross-layer optimal power allocation method provided by the invention, a satellite network control center can be enabled to feed back information according to a channel state provided by a physical layer, and the QoS needs of the different services are considered; the power allocation problem is modeled as the multi-user static non-cooperative game model; meanwhile, the corresponding encoding modes are adopted on the application layer aiming at the different services according to the different cross-layer solutions, so that the communication quality of a user in a mobile communication system can be comprehensively improved, and the system performance can be improved.

A semiconductor optical amplifier device includes an active layer, an n-type InP substrate, an n-type InP clad layer, a p-type InP clad layer, p-electrodes and n-electrodes. The active layer is made of, e.g., InGaAsP, and includes a saturable absorption region and optical amplification regions. A common modulated current is injected into each optical amplification region through the p-electrode. A modulated current is injected into the saturable absorption region through the p-electrode independently of the optical amplification region. The active layer receives injection light produced by adding additional noise light to an externally applied light signal, and emits output light produced by amplifying the injection light.

The invention discloses a method and a device for tracking a precoding matrix. The method comprises the following steps: using a matrix Euclidean distance as a measure to determine an adjacent precoding matrix group for each precoding matrix in a preset precoding codebook; and using the adjacent precoding matrix group corresponding to an optimized precoding matrix selected last time in the domainas a current alternative codebook space, and selecting an optimized precoding matrix for the time from the current alternative codebook space. The device for tracking the precoding matrix comprises acodebook determining module and a tracking module. The precoding tracking proposal of the invention can effectively improve the performance of a system while lower precoding feedback information content is maintained.

A semiconductor inspecting apparatus includes: a buffer memory whose width is matched to the greater of parallel bus width and the width of the number of serial lanes; a preceding stage bus switching unit that fills the buffer memory with input data without making a free space; equivalent transmission capacity conversion including a following stage bus switching unit that fills read data to the width of an arbitrary number of serial lanes without making a free space; a preceding stage bus switching unit that fills a buffer memory with input data without making a free space; and equivalent transmission capacity inverse conversion including a following stage bus switching unit that fills a parallel bus of arbitrary width with data read from a buffer memory without making a free space.

The invention relates to a wireless parallel transmission method for an energy and signal shared channel and belongs to the field of radio energy transmission. The wireless parallel transmission method is used for solving the problem that the implementation of synchronous transmission of wireless energy and information needs two channels. According to the wireless parallel transmission method for the energy and signal shared channel, provided by the invention, a system primary side circuit and a system secondary side circuit adopt a pair of coils as a shared channel and achieve the parallel synchronous transmission of the information and the energy by adopting the same frequency; the system primary side circuit achieves the forward transmission of the information in a variable frequency manner, and the system secondary side circuit achieves the reverse transmission of the information in a controllable rectifying manner. The method is applied to wireless radio energy transmission.

The invention discloses a space modulation transmission method. The method comprises steps: M transmitting antennas are selected from Nt transmitting antennas, wherein 0</=M</=Nt, M is the power of 2, space modulation mapping is carried out on data loaded in the M transmitting antennas; if M<Nt, data loaded in Nt-M transmitting antennas except the M transmitting antennas and data loaded in min{M,(Nt-M)} in the M transmitting antennas are subjected to space-time coding; and data after coding are transmitted. The invention also discloses a space modulation transmission device. When the technical scheme disclosed by the invention is applied, power-of-two constraints of the transmitting antenna number in the traditional system can be broken through, flexible antenna configuration is supported, and the performance of the system is effectively enhanced.

The invention discloses a phase-locked loop, a microwave modem and a phase jump suppressing method, belonging to the field of circuit control. The phase-locked loop comprises an error correcting module, a phase discriminator, a parameter selecting module, a time delay adjusting module, a filter and a control oscillator, wherein the parameter selecting module is used for selecting corresponding loop bandwidth parameters according to a current modulation mode; the time delay adjusting module is used for delaying the time for phase discriminator errors or the loop bandwidth parameters; and the filter is used for carrying out the filtering processing on the phase discriminator errors obtained by the phase discriminator according to the loop bandwidth parameters selected by the parameter selecting module. By selecting the loop bandwidth parameters according to the current modulation mode and carrying out time delay processing on the loop bandwidth parameters or the phase discriminator errors at the same time, the problem that the loop bandwidth parameters have response time delay when the modulation mode is changed is solved, and the effects of reducing the bit error ratio of the modern and reducing the risks on performance are achieved.

The invention provides a remote online upgrading method of a vehicle-mounted control terminal. The remote online upgrading method of the vehicle-mounted control terminal comprises the following steps of obtaining updating code data from an FTP server and writing the updating code data into an upgrading code file; and reading the value of an updating mark in the upgrading code file, writing code data in an updating code zone appointed by an updating code index into a user code zone in a flash memory when the value of the updating mark is equal to a preset value 3, and running a program in the user code zone after the updating code index points to another updating code zone. The invention also provides a remote online upgrading device of the vehicle-mounted control terminal. The remote online upgrading device of the vehicle-mounted control terminal comprises a control chip, a GPRS/3G/4G communication module and a storage module. The remote online upgrading method and device of the vehicle-mounted control terminal can upgrade software embedded in the vehicle-mounted control terminal, not only can reduce the bit error rate of software upgrading, but also solve the technical problem of running collapse after software upgrading failure of the vehicle-mounted control terminal and improve running stability and reliability of the vehicle-mounted control terminal.

Provided is a wireless communication apparatus for a non-orthogonal multiple access communication system. The apparatus comprises: a power adjustment unit which is used, for at least some of user equipment included in the communication system, dynamically adjusting the sending power of each of the at least some of the user equipment for each sub-carrier according to channel state information about the communication system, in order that the at least some of the user equipment perform uplink data transmission on corresponding sub-carriers with the adjusted sending power. According to the disclosed apparatus, method and system, at least one of the following technical benefits could be obtained: increasing the channel capacity of the communication system; reducing the bit error rate during the communication; and reducing the interference between corresponding user equipment in the communication system.

The invention discloses an OFDM peak-to-average ratio suppression method based on an alternating direction multiplier method for solving the problem that the existing optimization method for reducingthe OFDM peak-to-average ratio has high computational complexity. The implementation scheme comprises: taking frequency domain OFDM signal data carrier interference as an objective function, taking the peak-to-average ratio and the free carrier power as constraint conditions, establishing a non-convex optimization model; using the alternating direction multiplier ADMM to participate in the optimization process, and seeking the optimal solution, wherein the optimization process consists of two schemes, the ADMM method is directly used for solving in scheme 1, and a KKT point of an optimizationmodel can be guaranteed to be converged in the case of convergence. In the scheme 2, the optimization model is relaxed to obtain a relaxation model to guarantee the convergence, and the KKT point of the optimization model is infinitely approached in the case that the parameters are properly selected. Compared with the existing peak-to-average ratio suppression method, the OFDM peak-to-average ratio suppression method has the advantages of being able to obtain a smaller and more constant peak-to-average ratio, improving the system error rate performance and reducing the computational complexity, and the OFDM peak-to-average ratio suppression method is applied to the technical field of communication to improve the transmission quality of the communication system quality.

The invention discloses a free space optical receiving system based on a few-mode multi-core optical fiber. The receiving system is characterized by comprising a receiving antenna, a few-mode multi-core optical fiber, a mode demultiplexer, a detector and a receiver. The invention aims to further develop a free space optical receiving system, and provides the free space optical receiving system based on the few-mode multi-core optical fiber. The system is characterized in that the characteristic of high tolerance of the few-mode multi-core optical fiber is fully utilized when the received lightbeams are not aligned. According to the invention, the coupling efficiency of free space light can be improved, and the influence caused by atmospheric turbulence disturbance is reduced, so that thebit error rate during signal demodulation is reduced. In addition, the requirement on the aiming tracking precision of the received light beam can be reduced, and the method has very important significance for free space optical receiving systems such as long-distance free space optical communication and laser radar.

The invention discloses a single bus communication signal isolation circuit, wherein a first pull-up resistor is connected to a host interface end; the in-phase input end of a first comparison unit isconnected to the host interface end, and the inverting input end of the first comparison unit is connected to a first reference voltage; the control end of a first optocoupler is connected to the output end of the first comparison unit; a second pull-up resistor is connected to a slave interface end, the collector of the first optocoupler is connected to the slave interface end, and the emitter of the first optocoupler is connected to the ground at the slave interface end; the in-phase input end of a second comparison unit is connected to the slave interface end, and the inverting input end of the second comparison unit is connected to a second reference voltage; the control end of a second optocoupler is connected to the output end of the second comparison unit, the collector of the second optocoupler is connected to the host interface end, and the emitter of the second optocoupler is connected to the ground at the host interface end. The circuit solves the technical problem that thehost end and the slave end cannot be effectively isolated in the single bus communication process.

The invention relates to a digital wireless transmission technique in geotechnical engineering. It comprises data sampling instrument, communication controller, GPRS IP Moden, public telephone net, Moden, TDRemote, major control computer sequentially connected to form on site equipment, partially realizing communication, control and data transmission through public telephone net and indoor major control composed of major control computer, TDRemote and Moden. It is simple, high in precision, stable in performance, low in error rate, easy for operation. It can fit for complex working environment, like poisonous, emitting, and contaminated and so on.