163 results about "Carrier synchronization" patented technology

The invention relates to the technical field of high-frequency signal modulation, and discloses a high-frequency carrier synchronization signal modulation system. A carrier distortion compensation module of the system constructs a model based on a historical transmission data set, captures a phase jitter parameter, a spectrum leakage component and a modulation pulse sequence of a transmitting end carrier in real time, and outputs a reconstructed baseband parameter; the multi-dimensional distortion analysis module compares the reconstructed baseband parameter with a receiving end demodulation baseband parameter through composite difference detection, and generates a channel-level distortion coefficient tensor; the topological positioning network module is used for positioning signal out-of-step physical nodes and generating a probability distribution thermodynamic diagram by combining impedance characteristics of transmission nodes and signal path delay information; and the adaptive modulation strategy module starts a multi-band carrier injection mode for the high-probability out-of-step nodes according to the abnormal probability gradient of the thermodynamic diagram, and applies a phase disturbance test to adjacent transmission links. The system can improve the adaptability and accuracy of high-frequency carrier signal synchronous modulation.

The invention relates to the technical field of wireless communication, and discloses a communication equipment command and dispatch system based on artificial intelligence, the system maps the state of communication equipment into a standardized carrier phase disturbance mode, and after the disturbance mode is adaptively adjusted in combination with channel noise perception and conflict arbitration logic, the communication equipment is commanded and dispatched. Controlling the radio frequency front end to carry out injection; the adjacent communication equipment directly detects the disturbance mode to trigger the cooperative scheduling action by monitoring the physical error signal of the carrier synchronization loop of the adjacent communication equipment, and the implicit cooperative mode based on the physical layer beacon is constructed, so that the complex high-level signaling interaction required by the traditional scheduling is avoided, and the scheduling efficiency is improved. According to the method, the millisecond level, determined by a software protocol, of the collaborative response time between the devices is substituted into the microsecond level determined by the hardware physical layer response entscheid, the system can still maintain reliable transmission of scheduling instructions when facing high-density concurrent conflicts and strong channel noise, and a technical implementation path is provided for ultra-low-delay and high-reliability communication.

The invention discloses a time division duplex multi-carrier synchronous transmission method based on 5G, which relates to the technical field of communication, and comprises the following steps of: establishing a carrier mapping table, respectively mapping a plurality of logic carriers to predefined physical resource blocks, and marking uplink and downlink switching time slots according to a time division mode; after a user terminal receives a synchronization signal, alignment is carried out through a high-precision local clock and the reference time of a main base station, and a synchronization reference point is recorded with a nanosecond-level time resolution. According to the invention, through the dynamic synchronization control and frequency domain interference suppression technology, the synchronization stability and the data transmission reliability in a high-speed scene are significantly improved; a synchronous load scoring mechanism is introduced to realize efficient scheduling and conflict avoidance of synchronous resources in a multi-user concurrent environment; and in combination with interference weight estimation and an adaptive filtering strategy, the anti-interference capability and environment adaptability of the system are effectively enhanced, and the requirements of key services such as the Internet of Vehicles and industrial control on low-delay and high-reliability communication are comprehensively met.

The invention discloses a communication-detection integrated sonar signal design method and device based on multi-pulse composite modulation, and the method comprises the steps: dividing a total frame period into a detection sub-frame and a communication sub-frame, enabling the detection sub-frame to achieve the high-resolution distance measurement through employing a bidirectional linear frequency modulation (BILFM) signal, a communication sub-frame adopts a multi-frequency multi-phase composite modulation (MTPM) signal to realize high-bit-rate data transmission; after band filtering, orthogonal demodulation, low-pass filtering and down-sampling preprocessing are carried out on detection sub-frame echoes, distance and speed information is extracted by adopting fast-time low-sampling two-dimensional fast Fourier transform (2D-FFT), unambiguous Doppler frequency is recovered by utilizing the Chinese remainder theorem (CRT), and accurate speed measurement of long-distance and high-speed targets is realized; a communication subframe receiving signal is subjected to IQ demodulation after down-conversion, Costas loop carrier synchronization and matched filtering, and multi-frequency multi-phase coded data are extracted. According to the method, the time-frequency collaborative design of detection and communication is realized, the distance resolution and the speed measurement range are considered, and the signal bandwidth utilization rate and the underwater information transmission reliability are remarkably improved while the system complexity is kept low. The device comprises a processor and a memory, and an executable program for implementing the method is stored in the memory. The technology can be widely applied to the fields of unmanned underwater vehicles, ocean monitoring, underwater sensing networks and the like.

The invention discloses a carrier signal processing method and device based on an OFDM (Orthogonal Frequency Division Multiplexing) system and electronic equipment, and belongs to the technical field of communication. The carrier signal processing method comprises the following steps: acquiring signal energy of a current sampling point in a current signal segment in a digital signal; performing amplitude suppression processing on the signal energy of the current sampling point based on a comparison result of the signal energy of the current sampling point and reference energy; the reference energy is determined based on average signal energy of historical sampling points respectively corresponding to a plurality of historical signal segments in the digital signal, and the number of the sampling points of each signal segment in the digital signal is the same; and executing carrier synchronization processing based on the signal energy of the current sampling point after the amplitude suppression processing. According to the invention, filtering of impulse or impulse noise sampling points is realized, the accuracy of signal synchronization is improved, and the reliability of an OFDM system is improved.

The invention discloses a short burst SOQPSK carrier synchronization method based on an RPT-Net network. The short burst SOQPSK carrier synchronization method comprises the following steps: preprocessing a signal, and merging time domain data of the signal and quartic data into input data; a multi-level residual convolutional network is adopted to extract cross-symbol local phase features, fine phase changes in SOQPSK signals are captured through layer-by-layer stacked convolution operation, the gradient degradation problem of a deep network is relieved in combination with a residual connection mechanism, and the local characterization capacity for phase jump and frequency offset disturbance is enhanced; through a phase perception position coding module, the time domain signal is converted into a complex number form, an instantaneous phase is extracted, orthogonal basis coding is constructed to represent phase change, and deep fusion with position coding is carried out; a Transform coding layer is introduced, a multi-head self-attention mechanism is utilized to capture a long-distance symbol dependency relationship, global phase consistency constraint is optimized, long-term influence of frequency offset on signals is captured, and time sequence error propagation is effectively inhibited.

The invention discloses a parallel receiving method and system for high-speed 16 QAM (Quadrature Amplitude Modulation) data demodulation, and the method comprises the following steps: S1, carrying out the sampling of received intermediate-frequency 16 QAM data through a high-speed ADC (Analog to Digital Converter), and obtaining four paths of signals through the serial-to-parallel conversion function of the ADC; s2, converting the four paths of signals into 32 paths of parallel signals at a conversion rate of 1: 8 by using a serial-to-parallel converter special for the FPGA; and S3, carrying out digital orthogonal down-conversion on the 32 paths of parallel signals to obtain 16 paths of baseband signals of an I path and a Q path, and then sequentially carrying out matched filtering, timing synchronization, blind equalization, carrier synchronization, frame synchronization and 16QAM judgment decoding to complete parallel receiving. According to the invention, the requirement of high bit rate is met based on three key technologies of timing synchronization, blind equalization and carrier synchronization, and the receiving and demodulation recovery functions of high-speed data in a 16 QAM modulation mode can be effectively completed.

The invention discloses a dynamic environment distributed coherent communication carrier synchronization method and device, and relates to a distributed coherent communication technology, and the method comprises the steps: dividing system time resources according to time slots after time synchronization; in the synchronous time slot Ti, 1, the master node sends synchronous reference signals to all the slave nodes; each slave node Sn measures a phase change value between two same pilot symbol sequences in the received signal, estimates to obtain frequency deviation, and calculates phase and amplitude estimated values; each slave node Sn analyzes a data symbol in the received synchronous reference waveform signal to obtain a coherent cooperative micro time slot; each slave node Sn respectively measures the frequency, the phase and the amplitude of the reference signal in each time slot Ti; and performing distributed coherent cooperative communication from the plurality of slave nodes Sn to the master node M within the time interval of the synchronous time slot Ti, 1 and the coherent cooperative time slot Ti, j. According to the invention, the problem of distributed carrier synchronization caused by a dynamic environment can be solved, and the adaptive capacity of a system to channel state change is improved.

This application provides an inverter carrier synchronization system, belonging to the field of inverter control technology. The system includes multiple inverter devices connected via cascaded communication. Each inverter device includes a CPLD unit, a drive unit connected to the CPLD unit, a fault output unit, and a fault identification unit. The CPLD unit generates or forwards a carrier synchronization signal. The first contact of the relay in the fault output unit outputs a fault status signal to the next-level inverter device. The first-level inverter device acts as the master, and the fault status signal output by any normal inverter device is low. When any inverter device loses power or malfunctions, its relay disconnects, causing the output fault status signal to be high. Upon detecting the high-level fault status signal, the next-level inverter device automatically switches to become the master of the downstream inverter device. This system effectively suppresses high-frequency circulating currents in the system, improving system operating efficiency and stability.

The invention discloses a communication physical link multi-protocol sharing method during parallel operation of energy storage converters. The method is based on two general physical links, and efficient sharing of multiple protocols is achieved through the steps of hardware standardization integration, protocol intelligent adaptation, automatic switching of a drive circuit and the links, protocol signal two-way transmission, real-time state monitoring and the like. A unified adaptation platform is built on the hardware level, a multi-protocol special drive circuit and a high-performance MCU are integrated, the protocol level supports dynamic switching and parallel work of multiple protocols such as CAN, I2C, RS485, RJ45 and carrier synchronization signals, and scene changes can be responded without changing hardware. And during operation, through a full-dimension state monitoring and redundancy protection mechanism, transmission stability and rapid fault recovery are guaranteed. Redundant configuration of a special link and a driving circuit is reduced, the space utilization rate of a circuit board and the flexibility of the system are improved, and the diversified communication requirements of large-scale parallel connection of the energy storage converter can be quickly met.

The invention discloses an encryption burst communication receiving method based on an FPGA, and belongs to the technical field of burst communication. According to the invention, the problems of poor synchronization performance and poor anti-interference capability at the receiving end in the existing method are solved. According to the method, the carrier synchronization range is expanded by introducing the pilot frequency to enable the synchronization heads to be '1', the limitation that a conventional frequency offset estimation algorithm can only work under the condition that the Doppler frequency shift is smaller than 0.5 times of the symbol rate is broken through, and the capacity of the system for adapting to the high-dynamic environment is improved. A spreading code continuous tracking working mode is designed, coarse estimation and synchronization are carried out in a frame header part, spreading codes are still adopted in an information part, and continuous tracking is carried out, so that the system can adjust the phase of the spreading codes in real time in the whole frame to solve the problem of phase error accumulation caused by adopting a low-precision clock; the problems that when one frame of data at the sending end is long, the synchronization performance is reduced when a low-precision clock is adopted, and even effective synchronization cannot be achieved are solved. The method can be applied to the field of burst communication.

The invention provides a signal-to-noise ratio estimation method and device suitable for PSK (Phase Shift Keying) modulation. The method comprises the following steps: calculating the average power of an input signal sequence; estimating the average power of the pilot frequency sequence; and calculating a signal-to-noise ratio. According to the method, the influence degree of noise on the distance between the PSK modulation signal and the original point in the constellation diagram is estimated, a traditional method for calculating the signal-to-noise ratio by estimating the deviation degree of the actual signal from the ideal signal due to the influence of noise is replaced, high accuracy can still be kept when the signal is influenced by Doppler frequency deviation and sampling deviation, the method is more suitable for an actual communication system, and compared with the prior art, the method has the advantages of simple operation and low cost. In an actual communication system, signal-to-noise ratio estimation is usually carried out after signal timing synchronization and carrier synchronization processing, however, the signal-to-noise ratio calculation method provided by the invention can be used for estimating the signal-to-noise ratio after synchronization before synchronization according to PSK modulation characteristics, and has certain application advantages in scenes such as switching modulation waveforms according to the signal-to-noise ratio.

The invention belongs to the technical field of inverter parallel carrier synchronization, and relates to an inverter multi-machine parallel wireless carrier synchronization method, a control device and a system. The method is applied to a control device of each inverter in a multi-inverter parallel wireless carrier synchronization system, and comprises the following steps of: acquiring a power grid voltage, and calculating a zero-crossing signal period based on a difference between timestamps of two continuous zero-crossing moments of the power grid voltage so as to obtain a carrier reference period; calculating the cycle ratio of the carrier reference cycle to the current carrier cycle of the inverter, and rounding off the cycle ratio to obtain the number of carrier cycles which should be generated by the inverter in the carrier reference cycle; calculating a single theoretical carrier period of the inverter based on the carrier reference period and the number of carrier periods which should be generated by the inverter in the carrier reference period, and rounding off the single theoretical carrier period to obtain a target carrier period of the inverter; and carrying out phase modulation on the carrier wave of the inverter based on the target carrier wave period, so that the carrier wave of the inverter is synchronized with the power grid reference.

The invention discloses an interference communication integrated waveform generation method based on spectrum dispersion-multi-system phase shift keying. The problems of difficult communication information demodulation and high hardware implementation complexity in interference communication integration research are mainly solved. According to the scheme of the invention, the SMSP interference signal is formed by periodically expanding the chirp signal on the time domain, the communication information is modulated on the phase of the chirp signal, and the plurality of chirp signals carrying the communication information can cause dense false target interference at random positions on the radar, so that the interference and communication integrated signal is generated. At a communication receiving end, a first linear frequency modulation signal is adopted to perform carrier synchronization, so that the synchronization effect can be improved by using the high time width-bandwidth product characteristic of the linear frequency modulation signal, and communication information can be demodulated directly by using a coherent demodulation mode; at a radar receiving end, the signal can generate a radar interference effect with dense false target characteristics.

This invention discloses a power line carrier-synchronized 5G differential protection synchronization method for power distribution networks, comprising: a master carrier transmitter sending synchronization signal pulses, and a carrier receiver receiving the synchronization signal pulses simultaneously; the carrier receiver counting each time it receives a synchronization signal pulse; when the count value reaches a set value, the carrier receiver sending a synchronization signal to the data acquisition module of the intelligent power distribution terminal equipment; the data acquisition module receiving the synchronization signal and entering an interrupt to directly calibrate the AD sampling pulses, thereby achieving synchronization. This invention achieves a low-cost, high-synchronization, and delay-free differential protection function through power line carrier, enabling rapid fault location and timely repair in case of faults; it has broad feasibility and ease of use.

The invention discloses an angle error demodulation method for a burst communication signal, and relates to the field of satellite random access. According to the invention, angle error demodulation of burst communication signals is realized through synchronous sequence detection, open-loop AGC control and frequency domain angle error calculation. The arrival of a burst signal and the starting boundary of the signal are determined through synchronous sequence detection, signal power is quickly estimated through open-loop AGC control, AGC coefficient adjustment is carried out, a sum path signal is kept at a constant level, and angle error demodulation is directly carried out in a frequency domain through frequency domain angle error calculation on the basis that carrier synchronization does not need to be established. The method is suitable for angle error demodulation of burst signals with short signal duration and unfixed signal intervals, carrier synchronization does not need to be established, and the applicable signal modulation system is wide.

The present application belongs to the technical field of very low frequency fluctuation detection, and discloses a very low frequency station signal information extraction method and system based on a phase-locked loop. The present application amplifies and samples a wide frequency signal containing a very low frequency station transmitting signal, sets local MSK demodulation parameters, uses phase-locked loop technology to respectively perform carrier synchronization on the upper and lower frequencies of the MSK modulated signal transmitted by the target monitoring very low frequency station, extracts a baseband synchronization signal and a carrier synchronization signal from the phase-locked loops of the upper and lower frequencies, respectively, calculates the amplitude information of the upper and lower frequencies using the baseband synchronization signal, and further obtains the amplitude information of the target monitoring very low frequency station. The carrier synchronization signals of the upper and lower frequencies are used to extract the frequency of the carrier synchronization signal of the MSK modulated signal transmitted by the target monitoring very low frequency station, and further extract the phase offset information of the target monitoring very low frequency station. The present application can improve the accuracy of very low frequency station signal information extraction.

The invention discloses a generator parallel operation control method and system based on carrier synchronization, and belongs to the technical field of power electronic conversion. A generator parallel operation control method based on carrier synchronization is characterized in that the method is applied to a system comprising a synchronous enabling unit, a synchronous signal transmitter and a plurality of parallel converters connected with the synchronous enabling unit and the synchronous signal transmitter respectively, and the method comprises the following steps: for each converter, determining a counting difference value and sending the synchronous enabling unit; the synchronous enabling unit feeds back an adjusting signal to the corresponding converter based on a comparison result of the difference value sent by the carrier wave processor of each converter and a count value threshold until the difference values sent by the carrier wave processors of all converters are smaller than the count value threshold; then, synchronous enable signals are sent to the converters respectively; and each converter drives the IGBT to realize current conversion based on the synchronous enable signal. According to the method, synchronous impact and circulation are reduced by simulating dynamic approximation of a carrier and an actual carrier.

The invention discloses a service-adaptive satellite-borne non-uniform multicarrier demodulation device, and belongs to the field of digital signal processing. The method comprises the following steps of: firstly, performing orthogonal down-conversion and resampling filtering processing on a digital intermediate frequency signal sampled by an ADC (Analog to Digital Converter), processing the digital intermediate frequency signal by a non-uniform channelization splitter, and then serially outputting the digital intermediate frequency signal to a spread spectrum ratio self-adaptive variable burst capturer according to fixed quadruple sampling to capture a leading head and identify the spread spectrum ratio; the method comprises the following steps: completing symbol synchronization and de-spreading processing on an input signal according to a spread spectrum ratio, then completing carrier coarse synchronization and pattern word identification, completing modulation mode identification and carrier synchronization according to a pattern word, performing channel decoding through a multi-mode decoder to recover to an information bit stream, and outputting the information bit stream. And the information bit stream is sent to a service frame recombination processor for search identification and recombination splicing, and output is carried out after whole-frame CRC check is carried out. The method has the advantages of flexibility in use, low resource occupation and capability of realizing adaptive demodulation of variable-rate, multi-modulation-mode and multi-coding-mode service transmission signals without parameter configuration.

The present invention discloses a DSSS enhanced synchronization method combining PMF-FFT and an improved Costas loop, which is applied to the field of wireless communication technology. Traditional receiver designs typically employ independent frequency offset estimation and carrier synchronization methods, which are unsuitable for processing high-dynamic environments and low signal-to-noise ratio conditions. The present invention employs a maximum frequency offset estimation algorithm based on a partially matched filter-fast Fourier transform. By performing an FFT transform on the received signal, the frequency offset of the signal is accurately estimated, thereby effectively reducing the impact of the frequency offset on synchronization performance. Based on the frequency offset estimation, the receiver system designed in the present invention incorporates a Costas loop for carrier synchronization tracking. High-precision carrier recovery is achieved by locking the phase of the input signal.

The application provides a carrier frequency synchronization method applied to a frequency hopping data transmission system, the frequency hopping data transmission system comprising a transmitting end and a receiving end, and the method comprises the following steps: the transmitting end processes to-be-sent data into a data frame, adds a pilot head based on a ZC sequence to the data frame to form a frequency hopping data transmission frame, and sends a radio frequency signal carrying the frequency hopping data transmission frame to the receiving end; the receiving end acquires the radio frequency signal, processes the radio frequency signal into a digital signal; carrier synchronization processing is performed on the digital signal, carrier frequency scanning is performed on multiple frequency hopping points to screen effective communication frequency points; the starting position of the data frame is determined according to the effective communication frequency points, data demodulation and decoding are performed on the data frame, and original data is recovered. Through the application, the excellent autocorrelation characteristics of the ZC sequence and the intelligent double-peak detection mechanism are utilized to realize carrier frequency synchronization without strict time synchronization, and fast and anti-interference data transmission is completed.

The invention discloses a carrier synchronization control method suitable for a parallel converter of a doubly-fed wind power generation system, which belongs to the technical field of excitation converter equipment of the doubly-fed wind power generation system, and comprises the following steps: sending a square wave signal containing own carrier phase information to a bus through a synchronization signal generation circuit; generating a globally unified synchronization signal by using line AND logic; each module calculates the difference value between the own carrier phase and the reference phase according to the received synchronization signal, and compares the difference value with the average value of the carrier period adjustment quantity; if the difference value exceeds a set threshold value, a software filtering strategy is adopted for optimization; and the carrier phase of each module is dynamically adjusted through an indirect phase modulation method to realize carrier synchronization. According to the invention, carrier phase synchronization of the parallel converter of the doubly-fed wind power generation system can be realized in a power frequency period completely based on software control, a phase adjustment quantity filtering function is realized, and the reliability and the anti-interference capability of phase adjustment and the operation efficiency and the safety of the system are remarkably improved.

This application discloses a receiver positioning method, apparatus, communication system, storage medium, and electronic device, relating to the field of satellite navigation technology. The method includes: determining second information after signal recovery based on first information before signal loss of the satellite; tracking the signal based on a carrier digitally controlled oscillator frequency control word, a code digitally controlled oscillator frequency control word, and a code start point to determine the frequency error; during signal tracking, detecting whether the second code phase is aligned by code phase sliding; and, in response to the frequency error being within a preset range, the second code phase being aligned, and carrier synchronization, performing navigation calculations based on code epoch values ​​and the tracked third code phase to position the receiver. This application solves the technical problems in related technologies where repositioning of lost-lock signals cannot be achieved in weak signal scenarios, and the repositioning time is slow.

The invention relates to an IGCT (integrated gate commutated thyristor) power unit parallel dynamic current sharing system and method, which ensure the carrier synchronization consistency of each inverter module by constructing a high-precision synchronous clock signal with an error less than 10ns, thereby reducing the difference of switching moments; meanwhile, the high dominant frequency operational capability of 50MHz of a field programmable gate array (FPGA) hardware chip is utilized, and the PWM pulse width adjusting quantity with the resolution reaching 20ns is output, so that accurate adjustment of multi-machine parallel current is realized. Compared with a conventional current sharing method, the current sharing method has the advantages that the output current of each module can be accurately adjusted with high real-time performance, the problem of poor active adjusting capability in the prior art is effectively solved, and the current sharing performance and the system reliability of the high-power parallel device are remarkably improved.

The invention provides a power electronic transformer carrier synchronization control method and system based on a DBA topological structure, and the method comprises the steps: carrying out the time domain feature extraction processing through obtaining a switching signal waveform, generating an initial synchronization reference sequence, obtaining the magnetic flux change rate data of a high-frequency transformer, and carrying out the time domain feature extraction processing; the method comprises the following steps: carrying out characteristic correlation on an initial synchronous reference sequence to obtain a carrier period correlation degree and a phase difference distribution curve, generating a matching parameter of a carrier period and a phase based on the two curves, obtaining parallel circulating current amplitude data of a target loop, carrying out segmented threshold determination, and obtaining a circulating current amplitude overrun interval and an amplitude change gradient; and generating a frequency adjustment parameter based on the two, fusing the frequency adjustment parameter and the system operation state data to obtain a fused feature vector, performing phase alignment information reconstruction, generating reconstructed phase alignment information, and generating a multi-stage synchronous control instruction based on the reconstructed phase alignment information to control a switch time sequence. The carrier synchronization precision and the system operation stability of the power electronic transformer are improved.

The present invention discloses an alternative method for QPSK signal carrier synchronization, which mainly solves the problems of poor real-time performance and complex implementation of existing carrier synchronization technologies. Its implementation scheme is: in response to the needs of QPSK signal carrier synchronization, a sine signal and a cosine signal of the phase difference are calculated in real time; the phase difference interval is determined based on the obtained sine signal and cosine signal, and four phase shifts are performed on the received signal to obtain four interval signals; according to the phase correspondence between the four interval signals and the baseband signal at different phase differences and the determined phase difference interval, a certain interval signal that is in phase with the baseband signal is selected for output, and the sign bit of each interval signal is taken to finally restore the baseband signal. Compared with the existing carrier synchronization method, the present invention has good real-time performance, low processing delay, simple implementation, small amount of calculation, low resource consumption, and strong adaptability to deviation changes. It can be used for fast demodulation of QPSK signals in high-dynamic large-deviation Doppler frequency shift scenarios.

The application discloses a kind of based on dual three-dimensional memory hyperchaos SCMA-OFDM transmission system, the system includes sending end and receiving end, the user of sending end possesses respective codebook, J user shares K subcarrier, initial bit information and after the calculation of hyperchaos model of memristor triangle mapping chaotic codebook enter SCMA encoder and carry out codebook mapping processing, obtain encrypted SCMA-OFDM signal, for carrier synchronization, it is inserted pilot, after pilot, obtain frequency domain signal and information data using fast inverse fourier transform after the calculation of hyperchaos model of memristor triangle mapping, frequency domain signal is changed into time domain signal;Then to time domain signal is increased cyclic prefix CP and cyclic suffix CS to eliminate intercarrier interference, then parallel-serial conversion parallel signal is changed into serial signal, finally through up-conversion DUC complex signal mixing becomes real signal into transmission channel.The transmission system of regular hexagon chaotic codebook, its performance is improved by 2.5dB than traditional codebook.

The invention discloses a signal synchronization method, device and equipment, a medium and a computer program product, which are applied to the technical field of satellite communication, and the method comprises the following steps: determining a target mode corresponding to a burst transmission signal based on a pilot frequency proportion coefficient; the pilot frequency ratio coefficient is a parameter representing the available degree of the known symbol resource; performing timing synchronization on the burst emission signal to obtain a complete burst signal; and carrying out carrier synchronization on the complete burst signal based on an optimal carrier synchronization method corresponding to the target mode to obtain a frequency offset estimation value and a phase offset estimation value. Compared with a carrier synchronization method which completely uses fast Fourier transform at present, the carrier synchronization method disclosed by the invention has the advantages that the target mode corresponding to the burst transmission signal is determined based on the pilot frequency proportion coefficient, the optimal carrier synchronization method corresponding to the current burst transmission signal is determined based on the target mode, and carrier synchronization is carried out; therefore, the carrier synchronization method and device can improve the carrier synchronization effect.

The invention discloses a high-spectral-efficiency and high-speed FTN (Fourier Transform Network) transmission method based on pseudo code auxiliary carrier synchronization, which belongs to the field of high-frequency wireless communication, and comprises the following steps: a transmitting end composites a low-speed pseudo code pilot signal into a high-speed FTN signal by adopting a frequency division multiplexing mode to obtain a composite signal and outputs the composite signal; a receiving end performs down-conversion on the received composite signal, and the composite signal is separated by a filter to obtain a low-speed pseudo code pilot frequency sequence and a high-speed FTN sequence; carrying out carrier frequency offset estimation based on the low-speed pseudo code pilot frequency sequence to obtain a frequency offset estimation value; performing frequency offset compensation on a receiving end carrier by adopting the frequency offset estimation value to obtain a compensated high-speed FTN sequence; and carrying out symbol estimation on the compensated high-speed FTN sequence by adopting a forward backtracking continuous symbol sequence detection algorithm to obtain a received signal. According to the invention, the receiving sensitivity and the system robustness can be ensured while high-spectrum-efficiency transmission is realized.

The present invention discloses a capture method compatible with multiple modes and multiple sampling rates, and relates to the field of spread spectrum and non-spread spectrum communication systems in satellite communications. The present invention mainly adopts two parallel codewords and matching, accumulation and other processing, and utilizes changes in parameters such as data bit width, matching method selection, and sampling rate adjustment to flexibly adapt the capture synchronization of various signals. The use of a universal capture method solves the problem of customizing capture modules under different modes or different sampling rates, and can also assist in achieving preliminary estimation of carrier frequency deviation and accelerate carrier synchronization. The present invention is simple to implement, occupies few resources, and is highly operational and portable. It is very suitable for FPGA implementation and is conducive to the rapid synchronization of spread spectrum and non-spread spectrum signals.