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Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electronic environment of modern battlefield is becoming more and more complex, and the main-lobe deceptive jammer poses a serious threat to the survival ability of radar. For the traditional array radar can not resist the jammer with the same angle as the target. The waveform diverse array radar, represented by frequency diverse array, has extra degrees-of-freedom (DOFs) in the range domain by modulating the transmitter, which increases the flexibility of system design and signal processing, and provides an effective way to solve the problem of the suppression of mainlobe deceptive jammer. This paper summarizes the anti-jamming methods of waveform diversity array radar beamforming, points out its advantages in anti mainlobe deceptive jammer, and combs the technical difficulties and trends of anti-jamming in waveform diverse array radar. [ABSTRACT FROM AUTHOR]

Electromagnetic waves are transmitted by radars and reflected by different objects, and radar signal processing is highly significant as its analyses can lead to the acquisition of important information such as the situation and radial movement speed. Moreover, deep learning has gained much attention in several fields, and it can be utilized to implement radar signal processing. Compared with the traditional methods, deep learning can realize automatic feature extraction and yield highly accurate results; hence, in this paper, the application of deep learning algorithm in radar signal processing is studied. In addition, the study directions in radar signal processing are summarized into overfitting and interpretation. Thus, these two issues are being considered.

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of high time complexity in the signal recognition process by using convolution neural network, this paper proposed a new algorithm based on denoising auto-encoder and convolution neural network. Firstly, it performed the STFT on the radar emitter signal to obtain the time frequency image. And it used gray and threshold. It put processed image vectorization into the denoising auto-encoder. Then the denoising auto-encoder extracted the feature data. It put the reconstituted image matrix into the convolution neural network and used softmax classifier as classification and recognition. The simulation shows that the model using DAE is better than the original model and the time complexity decreases greatly. The recognition rate can reach 80% under SNR = - 6 dB. Besides, compared with the performance of traditional way, the recognition effect is obviously improved. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem of radar signal extraction of interleaved pulse sequences intercepted by reconnaissance receiver, according to the description technique of pulse recurrence interval (PRI), a pulse extraction algorithm is proposed based on the searching of PRI pulse sequence subpattern (PSS) cycle. In this algorithm, the idea of searching adjacent pulses intervals in traditional PRI searching algorithm is replaced by that of searching the PRI-PSS cycle. A two-dimensional extraction function consisting of time of arrival and paracycle of PRI PSS is constructed to store the number of matching pulses which conform to a certain assumed PRI-PSS cycle during the searching process. Then the PRI-PSS cycle is determined according to the maximum value of the function, thus the equivalent pulses can be extracted, realizing the signal extraction of complex type of PRI radar signals. The validity of this method has been verified by simulation experiments. [ABSTRACT FROM AUTHOR]

Microwave staring imaging as a new radar imaging mode, depends on antenna sensor radiating random signal respectively and spatial-temporal two-dimension random radiation field is formed. The received echo signal and pre-stored random radiation field are processed and the image is obtained. Due to the problem of strong correlation for electromagnetic signal, the scatterer point sidelobe is very high after directly correlated processing. To solve the proposed problem, this paper proposes a new method, which is based on Schmidt and Bjorck-Schmidt orthogonalization of the pre-stored random radiation field. The correlation of random radiation field between different scatterers is reduced by these two methods and the sidelobe of scatterer is suppressed. The ratio of signal-to-noise for processed image is enhanced. Finally, the fine focused image is obtained. The comparison between signals orthogonlized by Schmidt and Bjorck-Schmidt is shown in this paper and the characteristic of the pre-stored random radiation field is analyzed. Simulation experiments show that the proposed approach is feasible. [ABSTRACT FROM AUTHOR]

Under the complex environment including both radar signals and communication signals, a signal modulation recognition proposed, based on pulse description word (PDW), realizes multiple signal separation using the ability of the digital channelized receiver to process simultaneous arrival signals. It can accomplish the modulation type recognition and the parameters extraction depending on instantaneous frequency analysis and wavelet transform analysis. The simulation test results demonstrate the effectiveness of this proposed method. [ABSTRACT FROM AUTHOR]

In order to simplify the separation of radar echo and deception and to get the Jones vector of deception, a simple and convenient method to extract radar deception is proposed. By transmitting a group of relative polarization agile signals, the scattered wave and deception can be separated during the calculation of the signal output by the receiver, while utilizing the polarization effect of the target and the constant polarization state of deception. Compared with existing interference feature extraction algorithms, resources can be saved when this algorithm is implemented in single chip. The simulation results show that the relative errors of the calculation are less than 10% , when INR is more than 11.8 dB. [ABSTRACT FROM AUTHOR]

The Multiple-Input Multiple-Output (MIMO) radar was proposed in recent years. Using MIMO radar to detect the location of multi-target, a lot of algorithms are failure when the multi-target echo signals are coherent. Concerning this problem, a localization algorithm of coherent multi-target is presented in bistatic MIMO radar. The algorithm constructs virtual array for both the transmit and receiver array to de-correlate the coherent multi-target echo signals, and then the location of multi-target can be obtained. The estimated parameters are automatically paired without additional paring computation. The proposed method avoids the array aperture loss and the performance of angle estimation is improved. Theoretical analysis and simulation results verify the effectiveness of this method. [ABSTRACT FROM AUTHOR]

Velocity measurement and compensation is the key issue of wideband radar signal processing. The algorithm of range profile cross correlation (RPCC) can independently achieve velocity estimation in stepped-frequency (SP) signal, but with limited measuring accuracy. Through the analysis of the RPCC envelop and phase, two velocity estimation algorithms were put forward: waveform analysis of RPCC and peak phase of RPCC, and the theoretical performance was derived separately. Then, a novel approach was designed based on the combination of two algorithms above, which was defined as accurate velocity measurement of RPCC. The precision of the proposed approach is approximate to that of Doppler velocity estimation, which can not only satisfy the accuracy requirement of velocity compensation, but also make it possible to the micro-motion target measurement. Simulation result has verified the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Based on the signal processing theory of stepped-frequency radar, the target motion compensation for the system is studied. According to the characteristic of possible multi-target in radar eyesight under real scenario, the method of compensation in frequency domain is presented. The method can be used in the compensation of multi-targets with relative motion so as to supply the traditional compensation method in time domain. The results of computer simulation verified the validity of this method. [ABSTRACT FROM AUTHOR]

A new approach of automatic classification of the radar emitter signals is presented. This method is based upon the characteristics derived from instantaneous frequencies and contains three sequential steps: firstly, the instantaneous frequencies of radar emitter signals are extracted via the improved instantaneous autocorrelation algorithm; secondly, a two-times-normalizations based feature re-extraction approach is used to obtain the classification characteristic vector; finally, the kernelized fuzzy c-means clustering with validity assessment is carried out to categorize the considered signals automatically. The results of simulation experiments show that, the characteristic vector can reflect the differences of signals with different modulation types and has a good ability to resist noises. The proposed scheme of signals classification can achieve the overall success rate of above 95% , even at the signal to noise ratio of 6dB. [ABSTRACT FROM AUTHOR]

Keystone transform has been employed to remove range migration in high resolution range bins of moving targets among different stepped-frequency frames, and a new signal processing method using multi-frame stepped-frequency signals is analyzed and evaluated, with which high resolution range-velocity image of moving targets can be achieved. Theoretical analysis and simulation results showed that as long as parameters are properly designed, the method can achieve coherent integration of all moving targets between multi-frame stepped-frequency signals regardless of their unknown velocity. Moreover, thanks to great increase in coherent integration time, the capability of detecting small targets can be improved. [ABSTRACT FROM AUTHOR]

Under a symmetric multiprocessors (SMP) cluster environment, parallel computing of phased array radar simulation system is investigated to reduce simulation time. A coarse-grained message passing interface (MPI) distributed memory and fine-grained OpenMP shared memory hybrid parallel computing method is presented based on the relative independence of the phased array radar multibeam processing and the distance unit sampling computing in the signal processing simulation. Experimental results showed that the simulation speed is greatly enhanced by parallel computing. [ABSTRACT FROM AUTHOR]

Studies the measuring distance of wind profiling radar and the rules of change of structure coefficient for troposphere atmosphere turbulence(Cn²) for different seasons in China. According to the test records of wind profiler in recent years, analyzed and discussed experimentation data of north China and the principles of wind profiler compostion were introduced. Wind profiler radar equations and formulas of maximum measuring distance estimation were also derived. It is concluded that Cn² changes in different areas is the main reason for wind profiler measuring distance estimation errors. The test data proves the undulation of C̄n². with seasons is not very obvious and smaller than that of the boundary-layer atmosphere. Furthermore, the loss of signal processing is not the ignored factor for wind profiler measuring distance estimation. [ABSTRACT FROM AUTHOR]

Investigates a signal processor of electromic warefare(EW) digital receiver based on FFT/IFFT algorithm, and realized completely by FPGA constructed annularly. Four FPGAs implement respectively the high-speed data transmission interface, FFT/IFFT operation and signal detection in the time/frequency domain. The FPGAs run with distributed, multi-bus, parallel and pipeline mode. This processor can detect the parameters of carrier frequency and pulse description word for 4 simultaneous-arrival signals at most, and they need only about 20 ms to detect 4 signals while 256 K(1 K= 1 024) point FFT and 32 K point IFFT are adopted. The data receiving, operating and signal detection in time/frequency domain are realized on a board. [ABSTRACT FROM AUTHOR]

In order to provide a good simulation platform to study the passive radar seeker, video signal simulation was adoped to model and simulate the passive radar seeker, and a simulation platform was built up. In the experiments, the simulation results of passive radar seeker in typical war environment were provided, which verifies the correctness of our model and the robustness of our platform. [ABSTRACT FROM AUTHOR]