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target-localization
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Total 23 records
Parameter optimization for bistatic PCL radar
, Article ITST 2006 - 2006 6th International Conference on ITS Telecommunications, Proceedings, Chengdu, 21 June 2006 through 23 June 2006 ; 2006 , Pages 1256-1258 ; 0780395867 (ISBN); 9780780395862 (ISBN) ; Jafargholi, A ; Mousavi, M ; Bayat, S ; Nayebi, M. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2006
Abstract
In this paper the accuracy of measurement with respect to some parameters like baseline variance and DOA estimation and bistatic RCS is considered. The Radar designer can find the appropriate parameters to having the minimum error in target localization and maximum coverage range. © 2006 IEEE
Positioning in MIMO radars based on constrained least squares estimation
, Article IEEE Communications Letters ; Volume 21, Issue 10 , 2017 , Pages 2222-2225 ; 10897798 (ISSN) ; Behnia, F ; Maleki Sadr, M. A ; Sharif University of Technology
Abstract
This letter presents a novel solution for the problem of moving target localization in multiple-input multiple-output radar systems. The localization problem is formulated, based on least squares criterion, as a non-convex optimization problem and solved by semidefinite relaxation method. Then, an improvement technique, refining the initial solution by estimating the error terms, is proposed. Numerical simulations demonstrate that the proposed method achieves a significant performance improvement over the state-of-the-art methods. Specifically, the proposed method is shown to be more robust to the noise level compared with the existing algorithms. © 1997-2012 IEEE
An approximate ml estimator for moving target localization in distributed mimo radars
, Article IEEE Signal Processing Letters ; Volume 27 , 2020 , Pages 1595-1599 ; Amiri, R ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
This letter deals with the problem of moving target localization in distributed multiple-input multiple-output (MIMO) radar systems using time delay (TD) and Doppler shift (DS) measurements. The proposed solution to this problem consists of two stages. In the first stage, an initial estimation of target location is obtained by solving the formulated maximum likelihood (ML) problem based on the TD measurements. In the second stage, by recognizing the obtained position estimate in the previous stage as a priori data and exploiting the DS measurements, another ML problem is formulated, which is efficiently solved via a tractable numerical method to produce a simultaneous estimation of target...
Target Localization in MIMO Radars Using Stationary Moving Transmitters
and Receivers
,
M.Sc. Thesis
Sharif University of Technology
;
Behnia, Fereidoon
(Supervisor)
Abstract
Research on target localization in multiple-input multiple-output (MIMO) radars, has seen significant growth in recent years. In general, localization methods in these radars can be classified as direct and indirect methods. In the former, the cinematic specifications of target is directly extracted from the received signals, whereas in the indirect methods, different measurements are calculated from the received signals and then, the target position is estimated using the acquired measurements. In this thesis, by concentrating on indirect target localization methods and by taking practical problems, such as uncertainties in sensors position and velocity, asynchronous sensor clocks and...
3-D Target Localization in Distributed MIMO Radar Systems
, Ph.D. Dissertation Sharif University of Technology ; Behnia, Fereidoon (Supervisor)
Abstract
Target localization in multiple-input multiple-output (MIMO) radar systems has been an active research topic during the recent years. Generally speaking, MIMO radars can be classified, based on the antennas geometry, into colocated and distributed architectures.The former provides waveform diversity and the latter makes use of spatial diversity provided by widely separated configuration of antennas, both of which improve localization and detection performance. In this study, we focus on the latter case. In this thesis, we investigate the localization problem in two parts, i.e., positioning based on bistatic time delay measurements and hybrid localization using combination of time delay,...
Analysis of Effective Parameters in Localization Accuracy of Positioning Systems
, Ph.D. Dissertation Sharif University of Technology ; Behnia, Fereidoon (Supervisor)
Abstract
Target localization using positioning systems has long been considered by researchers in various fields.One of the important issues in localizing a target is the accuracy of its determined position. There are several parameters in the accuracy of position estimation. In a comprehensive view, these parameters can be divided into three general factors,including the relative geometry of the transmitters/receivers with respect to the target, the accuracy of measurements, and the type of target position estimator.The first factor, i.e. the relative geometry between the target and the transmit/receive antennas, plays an important role in localization accuracy. In the first part of this thesis, the...
Moving target localization by cooperation of multiple flying vehicles
, Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 51, Issue 1 , April , 2015 , Pages 739-743 ; 00189251 (ISSN) ; Saghafi, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
An algorithm, by cooperation of multiple flying vehicles, is developed to localize a moving target in the presence of measurement noise and mis-modeling. It works based on jointly sharing information and data fusion by using a recursive Bayesian estimator and a searching guidance law to direct each flying vehicle to a position where the probability of target detection is maximum. To evaluate this algorithm, a high fidelity simulation program with six degrees of freedom dynamics is also developed
Adaptive spatio-temporal context learning for visual target tracking
, Article 10th Iranian Conference on Machine Vision and Image Processing, MVIP 2017, 22 November 2017 through 23 November 2017 ; Volume 2017-November , April , 2018 , Pages 10-14 ; 21666776 (ISSN) ; 9781538644041 (ISBN) ; Ghanei Yakhdan, H ; Kasaei, S ; Sharif University of Technology
IEEE Computer Society
2018
Abstract
While visual target tracking is one of the noteworthy and the most active research areas in computer vision and machine learning, many challenges are still unresolved. In this paper, an adaptive generic target tracker is proposed that includes the adaptive determination of learning parameters from spatio-temporal context model, analysis of prior targets and confidence map for accurate target localization, and modified scale estimation scheme based on confidence map. According to spatio-temporal context model, the learning parameters are adaptively determined for achieving confidence map and target scale robustly. Moreover, analysis of the confidence map helps our tracker to change context...
Optimal sensor placement for 2-d range-only target localization in constrained sensor geometry
, Article IEEE Transactions on Signal Processing ; Volume 68 , 2020 , Pages 2316-2327 ; Behnia, F ; Amiri, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Localization of an emitting or reflecting target is one of the most important issues in a wide range of applications including radar, sonar, wireless communication and sensor networks. Due to significant effect on the positioning accuracy, designing the optimal sensor-target geometry has been considered as an important problem in the localization literature. The existing sensor placement methods mainly solve the problem in the cases without any constraints on the sensors locations. In the realistic scenarios, however, the sensors cannot be placed simply in arbitrary locations due to such constraints as the geographical limitations, communication problems between the sensor pairs and the...
Target localization geometry gain in distributed MIMO radar
, Article IEEE Transactions on Signal Processing ; Volume 69 , 2021 , Pages 1642-1652 ; 1053587X (ISSN) ; Behnia, F ; Amiri, R ; Farina, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
In this paper, we analyze the accuracy of target localization in multiple-input multiple-output (MIMO) radars with widely-separated antennas. The relative target-antennas geometry plays an important role in target localization. We investigate the optimal placement of transmit and receive antennas for coherent and non-coherent processing, based on maximizing the determinant of the Fisher information matrix (FIM), which is equivalent to minimizing the error ellipse area. The square root of the average determinant of the FIM can be expressed as a product of three parameters, namely the equivalent single radar gain, coherency gain and geometry gain. It is shown that the coherency gain of...
Compressive sensing for elliptic localization in MIMO radars
, Article 24th Iranian Conference on Electrical Engineering, 10 May 2016 through 12 May 2016 ; 2016 , Pages 525-528 ; 9781467387897 (ISBN) ; Amiri, R ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
In this paper, a sparsity-aware target localization method in multiple-input-multiple-output (MIMO) radars by utilizing time difference of arrival (TDOA) measurements is proposed. This method provides a maximum likelihood (ML) estimator for target position by employing compressive sensing techniques. Also, for fast convergence and mitigating the mismatch problem due to grid discretization, we address a block-based search coupled with an adaptive dictionary learning technique. The Cramer-Rao lower bound for this model is derived as a benchmark. Simulations results are included to verify the localization performance
Efficient positioning in MIMO radars with widely separated antennas
, Article IEEE Communications Letters ; Volume 21, Issue 7 , 2017 , Pages 1569-1572 ; 10897798 (ISSN) ; Behnia, F ; Maleki Sadr, M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
An algebraic closed-form solution for locating a moving target using a distributed multiple-input multiple-output radar system is proposed. The position and velocity of the target are estimated by presenting a two-stage weighted least squares algorithm. In contrast to existing research, the proposed estimator is shown analytically to be approximately unbiased and its variance is equal to the Cramer-Rao lower bound. Numerical simulations corroborate the theoretical studies and demonstrate the superiority of this algorithm over the existing methods. © 1997-2012 IEEE
An efficient weighted least squares estimator for elliptic localization in distributed mimo radars
, Article IEEE Signal Processing Letters ; Volume 24, Issue 6 , 2017 , Pages 902-906 ; 10709908 (ISSN) ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
Elliptic localization is an active range-based positioning technique that employs multiple transmitter-receiver pairs, each of which is able to provide separate bistatic range (BR) measurement. In this letter, an algebraic closed-form method for locating a single target from BR measurements using a distributed multiple-input multiple-output (MIMO) radar system is proposed. First, a set of linear equations is established by eliminating the nuisance parameters, and then, a weighted least squares estimator is employed to obtain the target position estimate. To refine the localization performance, the error in the initial solution is estimated in the sequence. The proposed method is shown...
Asymptotically efficient target localization from bistatic range measurements in distributed mimo radars
, Article IEEE Signal Processing Letters ; Volume 24, Issue 3 , 2017 , Pages 299-303 ; 10709908 (ISSN) ; Behnia, F ; Zamani, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
In this letter, the problem of target localization from bistatic range (BR) measurements in distributed multiple-input multiple-output radar systems is investigated. By introducing nuisance parameters, a pseudolinear set of BR equations is established. Then, a closed-form localization algorithm is developed, based on this pseudolinear set of equations and multistage weighted least squares estimation. This solution is shown analytically to attain the Cramer-Rao lower bound under the small Gaussian noise assumption. Simulations are included to support the theoretical studies. Unlike the existing studies where the variance of BR measurements is assumed to be independent of the corresponding...
Exact solution for elliptic localization in distributed MIMO radar systems
, Article IEEE Transactions on Vehicular Technology ; Volume 67, Issue 2 , February , 2018 , Pages 1075-1086 ; 00189545 (ISSN) ; Behnia, F ; Maleki Sadr, M. A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Elliptic localization is a range-based positioning technique exploiting multiple transmitter-receiver pairs, each of which provides separate bistatic range (BR) measurements. In this paper, a novel computationally efficient solution for locating a single target from BR measurements in distributed MIMO radar systems is proposed. Due to nonconvex nature of the associated maximum likelihood (ML) estimation problem, its globally optimal solution is difficult to obtain. We first reformulate the ML estimation as a nonconvex constrained weighted least squares problem. Owing to special structure of the resulting problem, it is recast as a convex problem, whose exact solution can be obtained in...
Efficient elliptic localization in the presence of antenna position uncertainties and clock parameter imperfections
, Article IEEE Transactions on Vehicular Technology ; Volume 68, Issue 10 , 2019 , Pages 9797-9805 ; 00189545 (ISSN) ; Kazemi, S. A. R ; Behnia, F ; Noroozi, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, an algebraic solution for elliptic localization in multiple-input multiple-output (MIMO) radar systems is proposed by taking the uncertainties in antenna positions and their clock parameters into account. Through nonlinear transformation and multi-stage processing, the target position is estimated in closed-form by successively utilizing the weighted least squares estimator. Theoretical analysis demonstrates that the proposed method is able to attain the Cramer-Rao lower bound (CRLB) performance under mild Gaussian error. The conditions for achieving the CRLB are derived as well. The numerical simulations confirm the analytical results and demonstrate significant performance...
Target localization in distributed MIMO radar from time delays, doppler shifts, azimuth and elevation angles of arrival
, Article 27th Iranian Conference on Electrical Engineering, ICEE 2019, 30 April 2019 through 2 May 2019 ; 2019 , Pages 1498-1503 ; 9781728115085 (ISBN) ; Navebi, M. M ; Amiri, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, we focus on the moving target localization problem in a multiple-input multiple-output radar with widely separated antennas. By exploiting jointly different types of information including time delay, Doppler shift and azimuth and elevation angles of arrival, we develop an algebraic closed-form two-stage weighted least squares solution for the problem. The proposed algorithm is shown analytically to attain the CramerRao lower bound accuracy under the small Gaussian noise assumption. Numerical simulations are included to examine the algorithm's performance and corroborate the theoretical developments
Moving target localization in bistatic forward scatter radars: performance study and efficient estimators
, Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 56, Issue 2 , 2020 , Pages 1582-1594 ; Amiri, R ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
This paper considers the localization of a moving target using a forward scatter radar consisting of a transmitter and an array antenna receiver. A direct positioning method based on maximum likelihood (ML) estimation is proposed and compared with the conventional two-step method in which the primary parameters, including Doppler shift and angle of arrival, should be determined in the first step. Moreover, closed-form expressions for Cramer-Rao lower bound of both methods are derived. The aforementioned methods are comprehensively compared in terms of positioning accuracy and computational complexity. Theoretical performance study, including determining the minimum required observation time...
Efficient joint localization and synchronization in distributed mimo radars
, Article IEEE Signal Processing Letters ; Volume 27 , 2020 , Pages 1200-1204 ; Amiri, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
This letter addresses the problem of joint localization and clock synchronization in distributed multiple-input multiple-output (MIMO) radar systems. While the well-known two-stage weighted least squares (WLS) method provides an acceptable estimate of target position when a rough approximation of antennas clock parameters, the drifts and offsets, is available, its performance can degrade quickly if the level of uncertainty in these values increases. The proposed method offers a solution for synchronizing the clocks while simultaneously improving the target position estimate. The uncertainty in positions of antennas is also taken into account. The presented method is shown to be approximately...
Efficient closed-form solution for 3-d hybrid localization in multistatic radars
, Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 57, Issue 6 , 2021 , Pages 3886-3895 ; 00189251 (ISSN) ; Amiri, R ; Behnia, F ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
In this article, an algebraic solution for localizing a moving target using a nonstationary multistatic radar system is proposed. By utilizing the quadruple hybrid measurement set, which consists of time delay, Doppler shift, angle of arrival, and angle rate measurements, the proposed method can estimate the target position and velocity vectors via a simple one-stage weighted least squares estimator without the need for introduction of the nuisance parameters, which enables us to locate the target with the minimum number of antennas. The proposed estimator takes the uncertainty concerned with the position and velocity of the antennas in its design. The proposed estimator is shown to be...