1727 results about "Down conversion" patented technology

The invention discloses an interference suppression method for a random phase modulation electromagnetic metasurface. The interference suppression method comprises the following steps: constructing a mathematical model for a modulated radar echo signal; wherein a random phase modulation electromagnetic metasurface is installed on the surface of a target, a radar transmitting signal enters the random phase modulation electromagnetic metasurface, and after random time domain phase modulation, a radar echo signal is generated; discrete sampling processing is carried out after digital down-conversion and dechirping are carried out on radar echo signals, and then additional phase information is estimated after self-mixing processing is carried out. Phase compensation is carried out on the radar echo signal after discrete sampling processing under the condition that noise is considered, and then time domain differential transformation and discrete Fourier transformation are carried out; estimating a phase mutation moment by using a subspace algorithm, and reconstructing an interference modulation sequence based on an estimation result; and demodulating random phase interference by using the reconstructed interference modulation sequence, and performing matched filtering processing to obtain an output signal.

The invention discloses an adaptive modulation anti-multipath unmanned aerial vehicle swarm communication method and system based on MIMO-OFDM, and relates to the technical field of wireless communication, and the method comprises the steps: receiving a down-conversion baseband; synchronization and compensation are carried out; removing a cyclic prefix and carrying out fast Fourier transform; estimating a channel and noise on the training and pilot frequency, and correcting a common phase; performing frequency domain equalization and soft decision, forward error correction and cyclic redundancy check according to the estimation to obtain a control parameter, decoding a payload according to the control parameter, and performing statistics to form a link quality indication; modulating coding, bandwidth and spatial mode, configuring mapping, power and weight, and packaging physical layer protocol data; carrier sensing conflict avoiding sending, confirmation and retry are adopted to generate media access statistics; and the routing selects the next-hop multi-hop forwarding according to the transmission quality, and performs end-to-end statistics and recharge. Through cooperation of hierarchical synchronization and phase correction with cyclic prefix and FFT, crosstalk is suppressed, channel noise scale optimization soft decision is robust, data decoupling is controlled, and end-to-end availability is improved through multi-hop self-healing recharge.

The present invention relates to a modular architecture for transmitting and / or receiving radio frequency (RF) signals using a phased antenna array. A first portion of the RF signal is transmitted / received by a master IC (21) and a second portion of the RF signal is transmitted / received by a plurality of satellite ICs (22). RF distribution between the master IC (21) and the satellite ICs (22) occur over a low-RF-loss interposer (51). The master IC (21) performs upconversion / downconversion between RF signal and a baseband or intermediate frequency signal.

The invention discloses an RFSOC-based FAST core array distributed collaborative observation and data fusion method and system, and the method comprises the steps: S1, system initialization: a master node RFSOC generates a global clock, achieves the phase synchronization of multiple board cards through an SYSREF differential signal, and completes the calibration of a three-stage clock tree; s2, signal acquisition and preprocessing: directly sampling a 3-8GHz radio frequency signal through an ADC (Analog to Digital Converter), and performing digital down-conversion to obtain a baseband signal; s3, intelligent resource scheduling: identifying a signal type based on an ESN (Echo State Neural Network), and dynamically allocating FPGA logic resources through an improved ant colony algorithm; s4, heterogeneous calculation acceleration: executing a 128-channel digital beam forming pipeline on the FPGA; s5, cross-domain data fusion; s6, collaborative observation planning; and S7, outputting data. The method is suitable for multi-beam synthesis, cross-region joint observation and mass data real-time processing scenes, and provides key technical support for solving the frontier scientific problems such as rapid radio storm origin and black hole activity monitoring.

The invention belongs to the technical field of low-orbit satellite communication, and discloses a satellite system for jointly improving measurement and control data transmission and communication application efficiency. A control unit is responsible for completing satellite calendar attitude calculation of satellite broadcast, analyzing a satellite working mode switching instruction according to ground station information stored by a storage unit, and then sending the instruction to each module unit; the two baseband processing units both support on-orbit reconstruction and loading, wherein the baseband processing unit A is used for completing measurement and control signal processing or user wide beam access signal processing; the baseband processing unit B is used for completing communication service signal processing or data transmission signal processing; the two up-conversion units respectively carry out up-conversion processing on a service link signal and a measurement and control link signal in the signal processing module, and the two down-conversion units respectively receive signals of the phased array transceiver antenna and the wide beam transceiver antenna and complete down-conversion processing. The measurement and control link can support a satellite measurement and control function and a communication wide beam access function in a time-sharing manner.

A circuit arrangement and to a method for operating the circuit arrangement, particularly a circuit arrangement for the DC power supply of a plurality of parallel electrolysers, where the circuit arrangement has a rectifier which converts an input-side alternating voltage into an output-side first DC voltage. Each electrolyser is respectively connected in parallel to the output of the rectifier by a down converter converting the first DC voltage into a second DC voltage such that the second DC voltage drops over the electrolyser. Each of the down converters is controllable and / or regulatable in order to adapt the level of the second direct voltage.

The invention discloses a frequency hopping signal real-time detection method and system based on FPGA + DSP. The system comprises a time frequency analysis module, a data communication module and a frequency hopping signal detection module. The method comprises the following steps: a time frequency analysis module performs analog-to-digital conversion and digital down-conversion on an intermediate frequency signal received from a radio frequency end, and performs short-time Fourier transform on a zero intermediate frequency signal by adopting a four-pipeline processing mode; the data communication module transmits the frequency spectrum information from the FPGA to the DSP through an SRIO protocol; the frequency hopping signal detection module calculates a dynamic threshold of a current frame signal according to the received frequency spectrum information, and completes preliminary detection of the signal according to a threshold value; and carrying out binarization processing and connected domain marking on the detected frequency spectrum, screening non-frequency hopping signals according to time-frequency information of a connected domain, and packaging and uploading parameter information of the detected frequency hopping signals to an upper computer. The method is simple in algorithm, low in hardware resource requirement and high in detection efficiency, and the feasibility of engineering implementation is improved.

The invention relates to the technical field of ground resistance detection, in particular to a single-core cable ground resistance detection method capable of resisting strong power frequency interference. High-frequency signals are injected in a non-contact mode through a coupling type capacitor clamp, background voltage and current signals are collected firstly, and injection frequency far away from power frequency and harmonic waves is selected through Fourier analysis; cancelling background noise by adopting a normalized least mean square adaptive filter to generate an enhanced signal; the signal is down-converted to a base band through digital quadrature demodulation, a Kalman filter estimates the amplitude and the phase in real time, and the state and noise parameters are periodically calibrated through a compressed sensing algorithm; and finally, loop impedance is calculated according to the voltage and current amplitudes and the phase difference to obtain grounding resistance. The method has the advantages of being non-contact, high in safety, strong in anti-interference capability, high in measurement precision and the like, and is suitable for monitoring the grounding state of the cable in a complex electromagnetic environment.

The invention discloses a frequency converter performance detection device, and relates to the technical field of frequency converters, the frequency converter performance detection device comprises a detection box, a heat-conducting fin is arranged in the detection box, and the heat-conducting fin is of a four-side square structure and forms a sealed cold and hot channel on the edge of an inner cavity of the detection box; the multiple damping shock absorbers are arranged at the bottom of the detection box; the vibration generator is arranged at the lower part of the detection box and is used for providing a vibration source for the detection box; the output end of the humidifier is communicated with the inner cavity of the detection box; and the output end of the cold-hot generator communicates with the cold-hot channel. The vibration generator, the humidifier and the cold and heat generator are arranged, the detection box is matched, multifunctional simulation of vibration, high-humidity, high-temperature and low-temperature environments in the peripheral environment is achieved, stability detection of the frequency converter under the extreme environment is achieved, and the cold and heat channel in a circulating circulation state is formed in the inner edge of the detection box; cold and hot air covers the detection box for multi-surface circulation, so that the distribution uniformity of the cold and hot air is improved.

The invention discloses a signal identification method based on broadband spectrum detection, and the method comprises the steps: carrying out the power spectrum estimation and signal detection of broadband IQ data through an FPGA, obtaining a signal frequency point parameter, and configuring a DDC module to complete digital down conversion; performing power spectrum density estimation and noise floor estimation on the narrowband IQ signal on the upper computer; preliminary classification is carried out by calculating a ratio parameter C1 of a maximum value and a second maximum value of a frequency spectrum, and when C1 is greater than a threshold, AM and a single carrier signal are discriminated by combining a frequency spectrum characteristic parameter C2 and an amplitude spectrum characteristic parameter C3; when C1 is smaller than or equal to a threshold, signal detection is carried out by adopting a double-threshold algorithm, and merging and screening in a multi-signal scene are completed; classifying based on a normalized zero center instantaneous amplitude spectrum density maximum value parameter C4, judging FM, MSK and FSK signals when the C4 is less than a threshold, and judging BPSK, QPSK, 8PSK and 16QAM signals when the C4 is greater than or equal to the threshold; according to the method, a multi-parameter joint judgment strategy is adopted, and the accuracy and the real-time performance of signal recognition are remarkably improved.

The invention relates to the technical field of data processing, and discloses a radio frequency fingerprint identification method based on a deep optimization adaptive attention mechanism, and the method comprises the steps: receiving a target equipment radio frequency signal, and carrying out the down-conversion, filtering and digital sampling of the target equipment radio frequency signal, and obtaining an original IQ data sample; preprocessing the original IQ sample to obtain a training data set; inputting the training data set into a convolutional neural network for pre-training to obtain a pre-training model; performing fine tuning on the pre-training model to obtain a downstream task model; and using the downstream task model to classify and identify unknown equipment data. Through time window segmentation and feature enhancement, the definition and consistency of radio frequency signals are improved, and meanwhile, the influence of noise and interference is reduced; and the effect of improving the capturing capability of the model on multi-scale and key features in a complex environment is achieved through the differentiated attention mechanism module.

The invention provides a broadband signal channelized receiving and high-precision reconstruction method and device, and belongs to the technical field of wireless communication broadband signal processing.The method comprises the steps that a preselection filtering module conducts first-stage channel division on broadband radio frequency signals; the receiving frequency conversion module performs down-conversion on the narrowband radio frequency signal to intermediate frequency, and the mirror image frequency is suppressed through an intermediate frequency filter; the digital channelization module performs down-conversion on the digital intermediate-frequency signal to a baseband, and realizes second-stage channel division by using a baseband digital channelization low-pass filter to obtain narrowband sub-signals; the high-precision reconstruction module synthesizes a broadband signal through up-conversion and interpolation filtering to obtain a reconstructed signal; the playback calibration module calculates the initial phase difference of the calibration signal among different channels for phase compensation, and obtains a reconstructed signal after phase calibration; and performing up-conversion on the reconstructed signal after phase calibration to radio frequency, and sending the reconstructed signal back to a frequency hopping communication system. According to the invention, the precision index and the engineering reliability of the channelized receiving and reconstruction design method are improved.

The invention relates to the technical field of ship communication, and provides an ocean ship communication method and system based on Ku wave band communication. Comprising the following steps: S1, configuring and deploying a Ku wave band satellite; s2, adjusting the corresponding transmitting frequency through the frequency offset of the transmitting end and the receiving end to perform frequency pre-compensation, converting the transmitted communication data into a satellite signal through modulation and coding by the transmitting end, and transmitting the satellite signal to the receiving end; and S3, capturing and performing down-conversion processing on satellite signals through a satellite antenna and a tuner, analyzing frequency and phase change characteristics of the satellite signals, adjusting parameters of a signal processor for compensation, demodulating and decoding the processed satellite signals through a modem, recovering original communication data, and performing Ku wave band satellite communication through a Ku wave band satellite communication technology. Non-blind area communication coverage of ocean ships is realized, and signal attenuation and interference are reduced by configuring a relay station, expanding the signal receiving and sending range, and dynamically adjusting the signal frequency through adaptive frequency control and a Doppler effect compensation algorithm.

This disclosure describes an auto-calibration of mixers in a quantum orchestration platform. Predistortion is computed according to an RF signal that is downconverted with a local oscillator tone that is offset from an upconverter tone. Three tones present in the original RF signal are distinguished and used to construct a cost function. The minimization of the cost function is used to cancel an unwanted LO leakage and an image tone. Because the quantum orchestration platform generates both the unconverted IQ signals and the cost function for their optimization, the optimization can be performed in real time inside a single device without the need to communicate with external devices. This allows for the optimization of single sideband upconverted signals in a fraction of the time it typically takes using distributed systems employing separate waveform generators and spectrum analyzers.

The invention relates to the technical field of signal analysis, in particular to a GNSS (Global Navigation Satellite System) detection method and system based on machine learning, and the method comprises the steps: receiving a navigation radio-frequency signal containing reality and deception, and carrying out the down-conversion of an RF (Radio Frequency) front end to obtain intermediate-frequency data; gNSS signal capture is completed by searching correlation peaks in frequency and code phases based on intermediate frequency data; in the capturing stage, a motion state, a correlation peak number, a noise value, capturing parameters and peak + / -1 chip sampling features are extracted and input into a machine learning classification model to judge whether cheating exists or not; if so, separating the deception signal from the real signal, and respectively sending the deception signal and the real signal into independent tracking channels; measuring an array element carrier relative phase by an array antenna, establishing a phase center model, and correcting to obtain an effective phase center and a differential baseline; according to the method, a deception azimuth angle and a pitch angle are obtained, a beam weight is calculated, a deception direction is subjected to null setting, a real direction is subjected to main lobe protection, and a weight value is fed back in real time to improve a signal carrier-to-noise ratio and locking stability. According to the invention, the problem that the existing commercial GNSS signal is low in power and easy to be interfered by deception is solved.

The invention provides a multifunctional satellite-borne integrated radio frequency system and device. The multifunctional satellite-borne integrated radio frequency system comprises a broadband low-profile integrated transceiver array, a reconfigurable integrated radio frequency front end and a flexible high-performance processing platform, the broadband low-profile integrated transceiving array adopts a multi-subarray design, has the capabilities of multi-beam signal transceiving, two-dimensional wide-angle beam scanning and received signal low-noise amplification, and adopts a low-profile and foldable structural design to adapt to the constraint of a satellite-borne platform; the reconfigurable integrated radio frequency front end has the capabilities of full-band signal up-down conversion processing and multi-channel full-interaction radio frequency routing; the flexible high-performance processing platform adopts a reconfigurable, open-type and high-reliability digital processing architecture, and has the functions of intermediate-frequency signal high-speed sampling, high-performance digital processing, software definition and on-orbit dynamic upgrading. According to the invention, a traditional discrete satellite-borne radio frequency system can be converted into a high-integration, multifunctional and conformal system, and the scale of the satellite-borne radio frequency system can be effectively reduced.

A communication system includes a plurality of repeater devices arranged at a plurality of different locations and are communicatively coupled over wired mediums. A first repeater device of the plurality of repeater devices obtains mmWave radio frequency (RF) and communicates, over a wired medium, the mmWave RF signal of the specified frequency to a second repeater device. The second repeater device extracts a plurality of different RF signals, corresponding to different communication protocols, from the mmWave RF signal and down-converts the extracted plurality of different RF signals. The second repeater device wirelessly distributes, from the mmWave RF signal, two or more different RF signals to end-user devices, packs content received from the end-user devices, and transmits upstream in the mmWave RF signal to the communication device via the first repeater device.

The invention provides a multi-channel radio frequency front-end module and a communication system, and the method comprises a local oscillator module which is used for generating a local oscillator signal; the up-conversion transmitting module is connected with the local oscillator module to receive the local oscillator signal; the down-conversion receiving module is connected with the local oscillator module to receive the local oscillator signal; the control system is respectively connected with the up-conversion transmitting module and the down-conversion receiving module and is used for generating a first radio frequency signal, sending the first radio frequency signal to the up-conversion transmitting module and receiving a second radio frequency signal from the down-conversion receiving module; wherein the up-conversion transmitting module is used for performing frequency mixing processing on a first radio frequency signal and a local oscillator signal and then outputting a first W-band signal, and the down-conversion receiving module is used for performing frequency mixing processing on a received second W-band signal and the local oscillator signal and then outputting a second radio frequency signal to a control system. Therefore, the embodiment of the invention can meet the application requirements in the millimeter wave radar field.

The invention relates to the technical field of signal processing, in particular to an intelligent blind equalization method and device for large-scale carrier frequency deviation, and the method comprises the steps: carrying out the down-conversion of an original received signal of a preset modulation type, so as to sample an original complex sampling point sequence with large-scale carrier frequency deviation; performing local information exchange, parameter correction and splicing on the original complex sampling point sequence to obtain a compensated complex sampling point sequence; performing pre-extraction and channel amplification on the compensated complex sampling point sequence to obtain pre-extraction features containing implicit channel state information, and further extracting spatial information and time sequence dependence in the pre-extraction features to balance multipath fading of the original complex sampling point sequence and obtain balanced output; and demodulating the original bit information of the original complex sampling point sequence according to the balanced output. Therefore, the problem that a blind equalization method in the related technology cannot effectively adapt to a time-varying multipath channel and a scene with large-scale carrier frequency deviation is solved.

A frequency offset estimation method for a satellite VDES system, characterized in that it includes the following steps: step 1, down-converting a carrier-containing signal output by an AD to move the signal to a baseband; step 2, performing CIC down-sampling processing on the down-converted signal to reduce the data rate to 4 times the symbol rate; step 3: performing frame synchronization processing on the CIC down-sampled signal to find the position of the frame header; step 4: performing coarse frequency offset estimation and compensation on the signal after the frame synchronization processing; step 5: performing Mpart fine frequency offset estimation on the signal after the coarse frequency offset compensation.

The invention discloses an independent double-single-side-band direct detection system based on geometric shaping and digital chaotic encryption, and belongs to the field of terahertz communication. According to the detection system, an external cavity laser ECL of a sending end generates continuous optical carriers, the continuous optical carriers are input into an I / Q modulator, a TX-DSP module generates two independent vector radio frequency signals of GS-QPSK and GS-NQAM through geometric shaping and a three-dimensional multi-vortex chaos system technology, the I / Q modulator is driven to modulate the input optical carriers, and the optical carriers are transmitted to a receiver. After being amplified, the terahertz signals are input into a one-way carrier photoelectric detector for frequency beating to obtain independent double-sideband terahertz signals, the independent double-sideband terahertz signals are input into a frequency mixer of a receiving end for frequency mixing with generated local oscillation signals, down-conversion of the signals is achieved, and fundamental frequency signals are obtained; and then the data are input to an RX-DSP module, normalization, down-sampling, signal separation, de-mapping, symbol-level and bit-level decryption and other operations are carried out, and finally two paths of original data are obtained to solve the bit error rate. According to the invention, the system communication capacity is improved, and the security of independent double-sideband signal transmission is improved.

This disclosure describes apparatuses and techniques for a switched multi-cell battery system for electronic devices. In some aspects, a switched multi-cell battery system may transfer, via a plurality of power control switches electrical power from a power adapter to components of the electronic device by charging battery cells in series and by discharging the battery cells in parallel or as a single battery cell. As a result, the switched multi-cell battery system may reduce or eliminate a voltage step-down conversion stage to increase a power-transfer efficiency of an electronic device. By doing so, charging times may be reduced or operating times may be increased, thereby improving users' experience with their electronic devices.

The invention discloses a differential signal synthesis circuit of a double-IQ mixer, which belongs to the technical field of radio frequency microwave testing and comprises two single-ended IQ mixing modules, a 180-degree phase shift module and an in-phase combination module or a power division module. The single-ended IQ frequency mixing module is used for up-converting the single-ended IQ baseband signal to radio frequency or down-converting the radio frequency signal to the single-ended IQ baseband signal; the 180-degree phase shift module is used for converting an input signal into two paths of signals with a phase difference of 180 degrees; and the power division module is used for converting the radio frequency input signal into two paths of signals with the phase difference of 0 degree. According to the invention, the IQ mixer with a differential structure is constructed, so that the microwave band of the IQ mixer is comprehensively improved in the index aspects of local oscillator leakage, even-order component suppression, common-mode interference suppression, signal-to-noise ratio and the like; according to the invention, single-ended IQ mixers with various types and complete frequency bands can be constructed into a differential structure form, and signal indexes in numerous application scenes are improved.

The invention discloses a broadband digital beam forming method based on a Farrow filter, and the method comprises the following steps: carrying out the DDC down-conversion and phase shift processing of a signal after the analog-to-digital conversion of a broadband signal is completed through an ADC; calculating the delay inequality of each array element signal relative to a reference array element, and decomposing the delay inequality into an integer sampling period and a fractional delay component; a fourth-order Lagrange type Farrow filter oriented to FPGA / DSP optimization is adopted to carry out fractional time delay compensation, and coefficients of the Farrow filter are dynamically adjusted through a polynomial expansion formula; and finally, performing complex weighted synthesis on each channel filtering signal to generate a directional wave beam. According to the method, high-precision fractional delay adjustment is achieved, the Farrow filter is adopted, the tedious process of recalculating coefficients can be omitted, only the P value is changed, and high-precision beam direction control can be achieved under the condition of low calculation amount.

The invention provides a stimulated Brillouin spectrum analysis device and method.The device comprises an optical circulator, a stimulated Brillouin medium, a probe light source, a double-sideband IQ modulator, an optical isolator, a dense wavelength division multiplexer, an up-down frequency conversion detector and a data acquisition board card, and light to be detected is injected into the stimulated Brillouin medium through the optical circulator; probe light enters a stimulated Brillouin medium after being modulated by a double-sideband IQ modulator, the modulated probe light and to-be-detected light generate characteristic frequency signals distributed on the two sides of the probe light frequency based on the stimulated Brillouin effect, stimulated Brillouin complex gain is calculated by demodulating light signals collected by an up-down frequency conversion detector, and the stimulated Brillouin complex gain is obtained. And the to-be-measured light information is obtained through inversion. By means of the scheme, high-resolution spectral analysis without scanning can be achieved, dependence on Brillouin frequency deviation in the optical fiber is eliminated, and the real-time performance of stimulated Brillouin spectral analysis is improved.

The invention specifically relates to a radar system for realizing communication and inductance integration, and the system comprises a field programmable gate array signal processing assembly which is used for generating an initial local oscillation signal and a customized initial emission waveform according to a control instruction of an upper computer, and outputting the initial emission waveform to an emission assembly, outputting the initial local oscillation signal to a local oscillation system component; the transmitting component is used for modulating a self-defined initial transmitting waveform, then generating a target transmitting signal and transmitting the target transmitting signal; the receiving component is used for receiving the reflected signal and modulating the reflected signal; the local oscillation system component is used for performing frequency conversion processing on the initial local oscillation signal and outputting a first LO signal subjected to up-conversion processing to the transmitting component, so that the transmitting component modulates the first LO signal and a customized initial transmitting waveform; and outputting the second LO signal subjected to down-conversion processing to a receiving component, so that the receiving component modulates the second LO signal and the reflected signal.

The invention discloses a broadband noise generation method based on predistortion calibration, and relates to the technical field of communication, and the method comprises the steps: S1, setting a flatness threshold value, and screening out an original noise signal needing to be calibrated; s2, generating an inverse filter coefficient and a filter suppression coefficient for the original noise signal; s3, performing frequency response compensation by using an inverse filter coefficient, performing band-pass filtering by using a filter suppression coefficient, performing down-conversion to a baseband, and reducing a sampling rate; and S4, comparing the processed signal with a flatness threshold value, and if the processed signal does not exceed the flatness threshold value, indicating that signal calibration is completed, otherwise, entering calibration again. By introducing a pre-distortion calibration mechanism, the inverse filter coefficient is calculated in real time to compensate the system frequency response, the spectrum distortion caused by a fixed filter is effectively eliminated, and the method has the advantages of realizing dynamic and adaptive filter adjustment, effectively reducing the manual participation frequency and improving the continuous operation capability and the test efficiency of the system.

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 relates to a method for realizing multi-channel ADC (Analog to Digital Converter) data synchronization processing based on an FPGA (Field Programmable Gate Array), which comprises the following steps that: the FPGA receives a clock frequency generated by an external clock generator and takes the clock frequency as a working clock of the FPGA; a plurality of groups of same-frequency clocks and same-phase clocks are generated in the FPGA and are respectively used as working clocks of the ADC chips; the FPGA receives sampling data of each ADC, an enable signal is set, and when the enable signal is effective, digital down-conversion, decimation filtering and FIR filtering are carried out on each sampling data; and after FIR filtering is completed, another enable signal ENend is generated, and data are further stored or transmitted to an upper computer. According to the method and the device for realizing the multi-channel ADC data synchronous processing based on the FPGA, the processor and the computer readable storage medium thereof, synchronous start and stop of the processing flow are controlled through the enable signals ENstart and ENend, synchronous processing of the multi-channel ADC data is ensured, accuracy and effectiveness are improved, and the method and the device have a wide application range.

The invention discloses a signal receiving method and device, which can reduce the peak power of a signal input to an analog-to-digital converter (ADC), thereby reducing quantization noise and improving signal receiving performance. The method comprises the following steps: receiving a first signal by a receiving device, performing down-conversion on the first signal to obtain a second signal, determining a third signal according to the second signal, sampling the third signal, and determining a target signal. Wherein the first signal comprises a target signal, and the target signal adopts comb mapping, that is, the target signal occupies one subcarrier in every M continuous subcarriers. The third signal comprises superposition of K delay signals of the second signal, the delay time associated with the kth delay signal in the K delay signals is # imgabs0 #, T is the time length of the first signal, k = 1, 2,..., K, delta is greater than or equal to 0, M is a positive integer greater than 1, and K is a positive integer greater than or equal to M.