Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

216 results about "Coherent processing" patented technology

CE-OFDM (Constant Envelope Orthogonal Frequency-Division Multiplexing) based radar communication integration system

The invention belongs to the field of radar technologies, and relates to a CE-OFDM (Constant Envelope Orthogonal Frequency-Division Multiplexing) based radar communication integration system. The invention is a CE-OFDM based super-resolution radar communication integration scheme which is provided on the basis of a traditional OFDM radar communication integration scheme, compensated through communication information, and capable of improving the effective data transmission rate and solving a problem that the PAPR of OFDM signals is too high. A transmitting terminal firstly turns data to be transmitted into CE-OFDM symbol frames through QAM (Quadrature Amplitude Modulation), IFFT (Inverse Fast Fourier Transform) and phase modulation, and a single pulse in a pulse repetition period is replaced by using a CE-OFDM symbol, so that the data transmission rate is improved, and the problem that the PAPR of transmitted signals is too high is solved. At a receiving terminal, received waveform pulses are demodulated, an inverse process of the transmitting process of the CE-OFDM system is carried out on the signals, and data can be demodulated; and the transmitting waveform is known, pulse compression processing is carried out on received echo waves, and super-resolution estimation for the distance and the speed of a target can be accomplished through decorrelation processing and an MUSIC algorithm after information compensation.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Compressive sensing theory-based Doppler ambiguity-resolution processing method

The invention discloses a compressive sensing theory-based Doppler ambiguity-resolution processing method, which comprises the following steps of: (1) performing non-uniform sampling on continuous echo pulses in a totally-coherent processing period by utilizing Q-fold pulse repetition frequency values; (2) designing the possible Doppler frequency range of a target, and ensuring the Q-fold pulse repetition frequency values do not have Doppler dead zones in the Doppler frequency range; (3) constructing a compressive sensing (CS) model by utilizing the time-domain under-sampling characteristics of sampled data in the totally-coherent processing period and the sparse characteristics of frequency spectrums of the target to be detected in the possible Doppler frequency range; and (4) resolving the CS model by utilizing an orthogonal matching pursuit (OMP) reconstruction algorithm to directly estimate the amplitude response of ambiguity-free Doppler spectrums. The method eliminates the restriction of the PRF multiplicity adopted by a radar system to the number of the targets to be detected, and simultaneously avoids the condition of false values caused by the influence of measurement errors in the conventional methods by taking the influence of noise on reconstruction results into account and performing de-noising operation when the CS model is resolved to estimate the amplitude response of the ambiguity-free Doppler spectrums by adopting the OMP reconstruction algorithm.
Owner:BEIHANG UNIV +1

Ancient architecture monitoring and early warning system based on internet of things

The present invention discloses an ancient architecture monitoring and early warning system based on an internet of things, comprising a wireless sensor network configured to monitor the ancient architecture environment, a cloud data server, and a real time monitoring platform. The wireless sensor network comprises a gateway node and a plurality of sensing nodes located everywhere about the ancient architecture, the sensing nodes include sensor modules, interface circuits, first controller modules and first wireless communication modules, and the gateway node includes a second wireless communication module, a second controller module and a network communication module. A nested and coherent processing flow comprising acquisition, transmission, fusion and display of information is formed through tight cooperation, therefore the continuity of the time and the efficiency of the spatial distribution of the data of monitoring the environmental factors associated with the ancient architecture are effectively improved, and at the same time the cost of manpower and material resources is greatly reduced; and moreover, the ancient architecture monitoring and early warning system based on the internet of things may make timely early warning in response to unexpected disasters and is capable of performing intelligent analysis and determination of monitoring data.
Owner:NANJING UNIV OF POSTS & TELECOMM +1

Mobile unit location by coherent processed satellite signal with fixed label signal

A method and system for finding the position of a mobile unit with respect to the satellites of a satellite network such as the Global Positioning System and with respect to the base stations of a wireless communications network. Each satellite transmits a signal that consists of a series of frames of a pseudonoise sequence. The frames of a signal received from the satellite network by the mobile unit are arranged as columns of a matrix and are processed coherently to provide estimated pseudoranges and estimated rates of change of pseudoranges for in view satellites. The coherent processing includes performing an orthogonal transform on the rows of the matrix, multiplying the elements of the matrix by Doppler compensation factors, and then, for each satellite in view, convolving the columns of the matrix with the pseudonoise sequence of that satellite. Other pseudoranges are inferred from synchronization burst sequences received by the mobile unit from one or more base stations. If the base stations are not mutually synchronized, reference units are provided to determine the time offsets between the base station clocks and the satellite network clock and to transmit these time offsets to the mobile unit, so that all the pseudoranges include the same bias relative to the satellite network clock. The pseudoranges are processed and reconciled by a dynamic estimator that includes a linear optimal estimator such as a Kalman filter, to produce successive estimates of the location of the mobile unit as the mobile unit moves.
Owner:CELLGUIDE

Radio frequency channelization method based on optical comb double modulation sidebands and implementation device

The invention discloses a radio frequency channelization method based on optical comb double modulation sidebands and an implementation device. The method comprises the following steps: generating coherent signal light and local oscillation light; the signal optical comb generation module modulating an optical comb with a comb tooth interval of FSRsignal; wherein the local oscillation optical combgeneration module modulates an optical comb with a comb tooth interval of FSRlocal, the modulation module modulating an RF signal based on the signal optical comb, the RF signal being filtered by thefilter, and performing coherent receiving processing after channel division is performed based on an output signal of the filter and the local oscillation optical comb. The device comprises a coherent light generation module, a signal optical comb generation module, a local oscillator optical comb generation module, a modulation module, a periodic filter, a channel separation module and a coherent processing module. According to the method and the device, the comb tooth interval of the local oscillation optical comb can be reduced, the requirement on the number of comb teeth of the signal optical comb is reduced, the energy utilization rate is improved, and the channelization difficulty is reduced.
Owner:SOUTHWEST CHINA RES INST OF ELECTRONICS EQUIP

Multi-beam combined angle measuring angle and point trajectory fusion method of MIMO radar targets under orthogonal waveforms

ActiveCN106066473AReduce complexityIncrease or decrease the number of received wavesWave based measurement systemsCoherent processingResult set
The invention relates to a multi-beam combined angle measuring angle and point trajectory fusion method of MIMO radar targets under orthogonal waveforms. The method includes the following steps that: the geometric model of radars in a Cartesian coordinate system is established, the number N of radar receiving array elements, the number L of radar received beams, and a radar power radiation space-domain range Omega are determined; a detection region corresponding to Omega is uniformly divided into K detection sub-regions, the received composite signals r<k>i(t) of a k-th detection sub-region which adopts the center pointing direction of an i-th radar received beam as a benchmark; conventional detection processing is carried out on the received composite signals r<k>i(t), so that the target detection result set Di of the i-th radar received beam is obtained; the angle measurement values of Mm target point trajectories in a target detection result set Dm of an m-th radar received beam, a target point trajectory set D<~>m containing the angle measurement values of the m-th radar received beam and the target point trajectory set sequence D containing the angle measurement values of L radar received beams are calculated sequentially; and point trajectory fusion is carried out, so that a target point trajectory set final sequence D<^> containing the angle measurement values of the L radar received beams in one coherent processing time is obtained.
Owner:XIDIAN UNIV

Weak signal quick capture method on basis of part correlation

The invention provides a weak signal quick capture method on basis of part correlation, which can meet the requirement of long coherent accumulation of a weak signal, and meanwhile, is suitable for the effect of wide-range Doppler change. The method comprises the following steps: generating 8-path data sequences, obtaining a duplication code, and allowing each path of the data sequence to be subjected to exclusive or operation together with the duplication code so as to obtain 8-path data auxiliary duplication codes; and allowing in-phase base band data and orthogonal base band data to be subjected to coherent accumulation operation through the auxiliary duplication codes and the duplication code, allowing the accumulation result of each path of data sequence to be subjected to FFT (Fast Fourier Transform), and then calculating the quadratic sums of the transformation results so as to judge whether the capture succeeds or not according to the maximal quadratic sum. According to the invention, the 8-path data sequences with different phase positions are adopted, a multi-path parallel coherent processing is adopted according to the processing results of the data sequences, and the coherent integration time in the signal capture process is prolonged as far as possible to an extent that the coherent integration can span several modulation data widths so as to improve the signal-to-noise ratio.
Owner:NO 513 INST THE FIFTH INST OF CHINA AEROSPACE SCI & TECH

Spatial ultrahigh-speed maneuvered target detection method based on RMDCFT (Radon-Modified Discrete Chirp-Fourier Transform)

The invention relates to a spatial ultrahigh-speed maneuvered target detection method based on RMDCFT (Radon-Modified Discrete Chirp-Fourier Transform). According to the method, firstly, modification is carried out based on the conventional Radon-Fourier transform method by using prior information of spatial target motion parameters, searching is carried out in a known target motion parameter range, and thus, target echo signals are extracted along the motion trajectory of a target; meanwhile, modification is also carried out based on the conventional MDCFT method, transform processing is carried out on the extracted target echo signals, and thus, the estimation on the frequency modulation rate of the target can be obtained; secondary phase of echoes is compensated based on the estimation, coherent accumulation is carried out on the target echo signals, and target detection is realized. The method has no need of predicting or estimating the fuzzy number of speed of the target and is applicable to the circumstances of limited CPI (Coherent Processing Time) and low signal-to-noise ratio; simulation results are compared with processing results of MTD, Radon-Fourier transform, FRFT (Fractional Fourier Transform) and RFRFT (Radon-FRFT) detection methods, experimental results show that the method provided by the invention can be used for effectively detecting the target when the CPI is limited and the signal-to-noise ratio is relatively low, and thus, the effectiveness of the method provided by the invention is proved.
Owner:CIVIL AVIATION UNIV OF CHINA

Frequency band fusion method and device based on adaptive iteration scheme

The invention discloses a frequency band fusion method and device based on an adaptive iteration scheme. The method comprises that 1) a multiband radar signal fusion model is established; 2) an initial phase difference and a linear phase difference of each frequency band radar signal are estimated via an all phase fast Fourier transform (apFTT) algorithm, and coherent compensation is carried on each frequency band radar signal; and 3) and multiband signal fusion can be realized for the frequency band radar signals after coherent processing via the adaptive iteration scheme. According to the method and device, the phase differences of the frequency band radar signals are estimated via the apFTT algorithm, thereby improving the estimation precision for the phase differences, and avoiding that estimation errors of radar signal model parameters caused by noises in a routine algorithm influence the subsequent coherent compensation precision and final fuse imaging quality. At the same time, fusion is carried out on the frequency band radar signals after coherent processing directly through the adaptive iteration scheme, thereby overcoming the difficulty in data prediction for blank frequency domains as required in a routine frequency band fusion algorithm.
Owner:INST OF ELECTRONICS CHINESE ACAD OF SCI

MIMO radar waveform modulation and demodulation method

The present invention discloses an MIMO (Multiple-Input Multiple-Output) radar waveform modulation and demodulation method. The method comprises the following steps of: according different transmitting channels at a transmitting end, modulating periodic target detection baseband signals to form different phase codes at the Doppler dimension; converting echo signals received by each receiving signals of a receiving end to digital echo signals after the echo signals are preprocessed, and performing windowed Fourier transform of the digital echo signals according to distance dimensions; converting the digital echo signals after windowed Fourier transform to a matrix in a distance-Doppler two-dimensional form, and performing decoding of the matrix in the Doppler dimension; and performing Doppler dimension coherent processing of the decoded signals to separate each transmitting channel to obtain two-dimensional output of the distance-Doppler frequency. The waveform modulation and demodulation method generates different frequency offsets at the Doppler dimension through phase encoding so as to achieve the purpose of distinguishing different transmitting channels and solve the mutual interference problem between the channels due to increasing of the transmit-receive antennas; and moreover, the signal real-time bandwidth and the computing resource consumption are not increased.
Owner:ZHEJIANG LIBANG HEXIN INTELLIGENT BRAKING SYST CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products