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Method for Estimating the Parameters of LFM Radar Signal

Chuan-Zhang Tan, Hong-Wei Li, Chang-Zhou Fan, Hui Yang
2017 ITM Web of Conferences  
In order to obtain reliable estimate of parameters, it is very important to protect the integrality of linear frequency modulation (LFM) signal.  ...  In this condition, estimating the parameters by fractional Fourier transform (FrFT) will cause the signal to noise ratio (SNR) decrease.  ...  The Gaussian-weighted fractional Fourier transform (GFrFT) [10] is presented for the parameters estimation of low duty ratio signal, and it reduces estimation errors combining with fourth-order algorithm  ... 
doi:10.1051/itmconf/20171108004 fatcat:hpdkwdszxbdijn7ay5zts4tk74

A New LFM-Signal Detector Based on Fractional Fourier Transform

Zhiping Yin, Weidong Chen
2010 EURASIP Journal on Advances in Signal Processing  
A new LFM-signal detector formulated by the integration of the 4th-power modulus of the fractional Fourier transform is proposed.  ...  Computer simulation results have confirmed the effectiveness of the proposed detector in LFM-signal detection.  ...  The authors would like to thank the anonymous reviewers who give some valuable comments for improving the quality of this paper.  ... 
doi:10.1155/2010/876282 fatcat:mz7o5rvc4zdchaal6sqnggqe5e

Multiple Moving Targets Detection and Parameters Estimation in Strong Reverberation Environments

Ge Yu, Shengchun Piao
2016 Shock and Vibration  
On the basis of received signal, we build a variance matrix of multiple beams by using modal decomposition, conventional beamforming, and fractional Fourier transform (FrFT).  ...  We then propose a novel detection method and an estimation method of parameters based on the constructed image.  ...  In discrete fractional Fourier transform, the optimal transform anglẽis dependent on rate of LFM signal.  ... 
doi:10.1155/2016/5274371 fatcat:az2nsiu6sfde5kw6l5prciyrvm

Analysis of multicomponent LFM signals by Teager Huang-Hough transform

Abdelkhalek Bouchikhi, Abdel-Ouahab Boudraa, Jean-Christophe Cexus, Thierry Chonavel
2014 IEEE Transactions on Aerospace and Electronic Systems  
LFM components are detected and their parameters are estimated from peaks and their locations in the Hough space.  ...  Advantages of THH transform over Hough transform of Wigner-Ville distribution (WVD) are: 1) cross-terms free detection and estimation, and 2) good time and frequency resolutions.  ...  Detection and estimation of the parameters of such signals are very important for electronic intelligence applications [2] [3] [4] .  ... 
doi:10.1109/taes.2014.120202 fatcat:tkjeex3etnakzklsmmho2gt7f4

Automatic Modulation Classification of LFM and Polyphase-coded Radar Signals

S. B. S. Hanbali, R. Kastantin
2017 Radioengineering  
To overcome this problem, we propose a new technique for detecting and classifying linear frequency modulation signal and polyphase coded signals using optimum fractional Fourier transform at low SNR.  ...  There are several techniques for detecting and classifying low probability of intercept radar signals such as Wigner distribution, Choi-Williams distribution and time-frequency rate distribution, but these  ...  Acknowledgement The authors would like to thank Hatem Najdi for his helpful discussions and for reviewing the final version of this paper.  ... 
doi:10.13164/re.2017.1118 fatcat:vtjf6neg2zhrdf22h5j3vi2qqy

Linear frequency-modulated signal detection using Radon-ambiguity transform

Minsheng Wang, A.K. Chan, C.K. Chui
1998 IEEE Transactions on Signal Processing  
Since the AF of LFM signals will pass through the origin of the ambiguity plane, the line integral of the Radon transform is performed over all lines passing through the origin of the ambiguity plane.  ...  The result is a tool for LFM detection, as well as the time-varying filtering and adaptive kernel design for multicomponent LFM signals.  ...  The authors appreciate one of the anonymous reviewers for making many useful suggestions and Dr. S. Wang for reviewing preliminary drafts of this paper.  ... 
doi:10.1109/78.661326 fatcat:zpqe6w7qojbgzkm72vb77muwo4

A study on parameter estimation and suppression for smeared spectrum jamming based on short-time Fourier transform

Chuanzhang Wu, Baixiao Chen, Minglei Yang, Mei Dong
2020 EURASIP Journal on Wireless Communications and Networking  
The proposed method is to estimate the parameters of the jamming signal based on the STFT result, and then the jamming signal is reconstructed and suppressed form the mixed signal.  ...  Based on this assumption, the estimation steps for different parameters of SMSP jamming are given, including the number of sub-waveforms, the amplitude, and the time delay.  ...  W proposed the parameter estimation method and carried out the numerical experiments. B. C analyzed the system model and provided the paper organization. M. Y and M. D improved the writing.  ... 
doi:10.1186/s13638-020-01728-y fatcat:h7srgrg5gzh23ixvqwxx32suxu

Fractional Fourier Transform for Ultrasonic Chirplet Signal Decomposition

Yufeng Lu, Alireza Kasaeifard, Erdal Oruklu, Jafar Saniie
2012 Advances in Acoustics and Vibration  
This study has a broad range of applications of importance in signal detection, estimation, and pattern recognition.  ...  Signal processing results show that FrFT-CSD not only reconstructs signal successfully, but also characterizes echoes and estimates echo parameters accurately.  ...  Acknowledgments The authors wish to thank Curtis Condon, Ken White, and Al Feng of the Beckman Institute of the University of Illinois for the bat data and for permission to use it in the study.  ... 
doi:10.1155/2012/480473 fatcat:xj72ob6dtfd5xoysmquizgpohy

Robust direction of arrival estimation approach for unmanned aerial vehicles at low signal-to-noise ratios

Jian Lu, Jian Yang, Liu xinghai, Guangbin Liu, yue zhang
2019 IET Signal Processing  
The conventional methods used to estimate the direction of arrival (DOA) of linear frequency modulated (LFM) signals at low signal-to-noise ratios (SNRs), such as the echoes reflected by a small unmanned  ...  Through coherent integration, the algorithm then extracts all the peaks of the target echo waveform, which are then used for the construction of a fractional autocorrelation matrix.  ...  DOA estimation of UAV echoes based on FrFT Fractional Fourier transform Generally speaking, a coherent radar detects small UAVs in flight by transmitting LFM pulses, which can be expressed as x 0 (t)  ... 
doi:10.1049/iet-spr.2018.5275 fatcat:ppgewd77gfhfneewrcarg7qfr4

Coherent-Like Integration for PD Radar Target Detection Based on Short-Time Fourier Transform

Xiao-wei Zhang, Lei Zuo, Dongdong Yang, Jian-Xin Guo
2019 IET radar, sonar & navigation  
In the context of white complex Gaussian noise, this study presents one constant false-alarm rate mono-pulse detector for both the narrowband and wideband pulse-Doppler (PD) radars.  ...  To this end, coherent-like integration is proposed to improve the signal-to-noise ratios of one radar echo. The PD radar returned signals are first performed by stretch processing.  ...  Acknowledgment The authors thank the editor and the reviewers for their constructive comments that helped us to improve the paper. This work was partly supported by the National Natural Science  ... 
doi:10.1049/iet-rsn.2019.0190 fatcat:5hakrlonsjbohah47bhv2k3eyy

A TDoA Localization Scheme for Underwater Sensor Networks with Use of Multilinear Chirp Signals

En Cheng, Xizhou Lin, Shengli Chen, Fei Yuan
2016 Mobile Information Systems  
This method transforms the combined rates of MLC into symmetry triangle rates and then separates the multiuser signals based on the transformed rates by using FrFT.  ...  In order to increase the detection efficiency of MLC, we propose a fast efficient detection method called mixing change rate-fractional Fourier transform (MCR-FrFT).  ...  Acknowledgments This work was supported by the National Natural Science Foundation of China (61571377 and 61471308).  ... 
doi:10.1155/2016/2098927 fatcat:c6fg6bthajagxeepyitcayt4fa

Fractional synchrosqueezing transformation and its application in the estimation of the instantaneous frequency of a rolling bearing

Xin Li, Zengqiang Ma, Suyan Liu, Feiyu Lu
2020 IEEE Access  
as the convolution of the FRFT and a window function and is calculated by * ( , ) ( ) ( ) ( , ) STFRFT t u x t g K u d          . (23) 3) THE DETECTION AND PARAMETERS ESTIMATION OF AN LFM  ...  In [47] , ensemble empirical mode decomposition based on a fractional Fourier transform was proposed to detect and estimate the parameters of multicomponent chirp signals, but with the limitations of  ...  This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication.  ... 
doi:10.1109/access.2020.3010629 fatcat:y7nc4fcmvnhvvfo2bvguljzsde

DOA Estimation of Nonstationary Signals [chapter]

Moeness G. Amin, Yimin D. Zhang
2014 Academic Press Library in Signal Processing  
The spatial time-frequency distribution (STFD) framework is used to re-introduce highresolution direction-of-arrival estimation methods, in which a matrix of auto-and cross-bilinear distributions of the  ...  DOA ESTIMATION OF NONSTATIONARY SIGNALS • Auto-term: A sample in the time-frequency domain which pertains to the time-frequency distribution of an individual component of the signal. • Cross-term: An artifact  ...  The Wigner-Radon transform and fractional Fourier transform (FrFT) are well known techniques that utilize these LFM signal properties. These techniques can be used for DOA estimation of LFM signals.  ... 
doi:10.1016/b978-0-12-411597-2.00017-5 fatcat:qu2z7vx5rba5hmp3gxqkzqi63e

The effect of amplitude modulation on subharmonic imaging with chirp excitation

Sevan Harput, Muhammad Arif, James Mclaughlan, David J. Cowell, Steven Freear
2013 IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control  
Linear frequency modulated (LFM) and nonlinear frequency modulated (NLFM) chirp excitations allow independent control over the signal bandwidth and duration, therefore in this study LFM and NLFM signals  ...  The subharmonic response can be improved by using wideband and long duration signals.  ...  The signal spectra for all waveforms were calculated by using Welch's method of power spectral density estimation to control the bias and variance of the estimated spectrum [41] .  ... 
doi:10.1109/tuffc.2013.2852 pmid:24297019 fatcat:7nwkgcrq75gencwfm75rg3yzfq

An Efficient SAR Ground Moving Target Refocusing Method Based on PPFFT and Coherently Integrated CPF

Dong Li, Chengxiang Zhang, Haining Ma, Hongqing Liu S, Jia Su, Qinghua Liu
2019 IEEE Access  
First, based on the known radar platform motion parameters, the range curvature correction is completed, and then the range walk is corrected using the efficient PPFFT via estimating the slope of the range  ...  exploiting the twodimensional (2-D) coherently accumulation characteristics and the energy of all the scatterers in moving target for estimating motion parameters.  ...  To produce a high-resolution, the parameters of the LFM signal need to be accurately estimated as well.  ... 
doi:10.1109/access.2019.2930560 fatcat:riykmnirzzgalavyq5ur5vjv2i
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