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In order to improve the detection probability of range-spread targets in white Gaussian noise, a detector using waveform contrast is proposed based on multiple-pulse trains. Firstly, sliding cross correlation is utilized to eliminate the detrimental influence of range migration. Then, arithmetic mean algorithm is adopted to synthesize the final high-resolution range profiles (HRRPs). Finally, the...
Constant False Alarm Rate (CFAR) is commonly used in RADAR and SONAR to detect targets in different clutter situations. We aim to design a CFAR detector to be used in FMCW radar which is easily configurable and is best suited to its operational environment. Mathematical formulation and MATLAB simulation of six different CFAR detectors are presented in this paper. The performance of these detectors...
To solve the inefficiencies and high false alarm probability problem of the target detection in synthetic aperture radar (SAR) images and to improve the weakness of the two-parameter CFAR detector, a fast constant false alarm rate(CFAR) algorithm based on Weighted Parzen-window clustering (WPWC) is proposed. The principles and flow of the WPWC algorithm is introduced and a fast two parameter CFAR...
The Ordered Data Variability (ODV) technique is introduced into hybrid clutter map/L-CFAR technique, which is used to process the echoes on the clutter map spatially. The new method is called as Clutter Map/ODV (CM/ODV) technique. An analytic expression of detection probability in homogeneous environment is presented, and detection performance in three different situations in nonhomogeneous environment...
The high-resolution radar echo is modeled as a range-spread target. Based on the generalized likelihood ratio test design procedure, the range-spread target detection in spherically invariant random vector clutter is addressed. And a binary integrator with constant false alarm rate property is proposed to detect the whole range-spread target, after single target scatterer detection in each range cell...
Adaptive detection for distributed target or targets in non-homogeneous environments is studied in this paper. It is assumed that the covariance matrix of the secondary data Ms is a random matrix following inverse Wishart distribution with its conditional expectation proportional to that of the primary data, i.e. E(Ms | Mp)= γMp. Firstly, the maximum likelihood estimator (MLE) of Mp, γ and target...
Target detection is a hot topic and key technique of SAR image interpretation. There are many detection methods, such as CFAR detector and Extended Fractal (EF) feature detector. In order to overcome their shortcomings and combine their merits at the same time, the combination of some different detection methods need be implemented. Granularity computing is just an approach that solves the problem...
The research on detection of range-extended targets has been a focus of UWB radars. The paper introduces weighted accumulation and adaptive searching to the IPCP detection, and theoretical value of detection threshold is derived in detail. Related experiment and simulation confirm that weighted accumulation increases SNR effectively and adaptive searching basically eliminates the negative effects...
An improved CFAR detector for non-homogeneous clutter environment is proposed. At LFMCW radar receiver, after moving target detection (MTD) and linear-law envelop detector, CFAR detector is usually adopted to detect radar targets, the threshold of CFAR detector should be adaptive to the local background noise/clutter environment. Interfering targets often exist in the leading and lagging windows of...
Target detection is one of important roles of radar systems. In this paper, we present a detection method using total correlation based on information theory for noise radar systems which enables a system detects multiple targets at low signal to noise ratio regimes. The proposed method utilizes the largest eigenvalue of the sample covariance matrix to extract information from replica of the transmitted...
In this paper we consider the problem of radar detect a fluctuating target in Gaussian clutter with unknown covariance. To this end we devise the detector based on the prior posterior ratio test (PPPT) criterion. The likelihood ratio is the prior-posterior PDF ratio of amplitude of the echo from the target. For the estimate of the unknown covariance of the clutter, We resort to the Maximum likelihood...
Target detectors using polarimetry are often focused on single (coherent) targets, since these are the ones that can be more simply characterized polarimetrically. The new proposed algorithm is aimed at the more difficult problem of partial target detection (i.e. targets with any degree of polarization). A new feature vector is defined starting from the coherency matrix, and then a perturbation method...
Target detection of marine feature is a major topic for the security and monitoring of coastlines. Synthetic Aperture Radar (SAR) has been shown to be particularly useful for this application because of its all-weather and night capability. In this paper a new ship and iceberg detection methodology is described. The algorithm proposed is based on a perturbation analysis in the target space recently...
Many current radar-based human detection systems employ some type of Doppler or Fourier-based processing, followed by spectrogram and gait analysis to classify detected targets. However, Fourier-based techniques inherently assume a linear variation in target phase over the aperture, whereas human targets have a highly nonlinear phase history. This mismatch leads to significant loss in SNR and integration...
This paper expands on the author's previous work by adapting the CLEAN algorithm to address low signal to noise (SNR) targets. The Reformulated CLEAN Detector is presented which is shown to allow the detection of low SNR targets in the presence of large targets. Performance results are presented that show how good performance can be attained by combining the correlator, CLEAN Deconvolver and Reformulated...
This paper describes in details the performance of an advanced detecting algorithm for multi-sensor target Track Before Detection (TBD) through the Hough Transform (HT). The detection algorithm employs the idea of using the Hough Transform for joint detection of linear trajectory targets. The polar modification of the TBD-HT approach is applied to a multi-sensor Polar Hough detector for multi-sensor...
In this work we prove that if the texture of compound-Gaussian clutter is modeled by an Inverse-Gamma distribution, the optimum detector is the optimum Gaussian matched filter detector compared to a data-dependent threshold that varies linearly with a quadratic statistic of the data. The compound-Gaussian model presented here varies parametrically from the Gaussian clutter model to a clutter model...
Most significant part of radar target detection problems can be solved by using the method of statistical detection theory. Here the objective of the proposed optimal detection algorithm is to give a maximum detection probability for fixed false alarm probability. It is assumed that target is stationary and energy reflected from the target is distributed. The proposed detection algorithm has a squared...
We consider the problem of target detection for coherent multi-input multi-output (MIMO) radar with widely separated antennas in the presence of phase synchronization mismatch between the transmitter and receiver pairs. First, we introduce a data model using von-Mises distribution to represent the phase error terms. Then we employ expectation-maximization algorithm to estimate the error distribution...
This paper is concerned with a moving target detection using time reversal in dense multipath environments. We show that the Doppler shift in the time reversal re-transmission simplifies the detector design, yet still achieves the focusing effect. Thus, the Doppler diversity is utilized to achieve high target detectability by time reversal.
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