In this paper, we investigate into joint direction-of-departure (DOD) and direction-of-arrival (DOA) estimation for bistatic multiple-inputmultiple-output (MIMO) radar in the presence of gain-phase error and mutual c...
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ISBN:
(纸本)9781538647523
In this paper, we investigate into joint direction-of-departure (DOD) and direction-of-arrival (DOA) estimation for bistatic multiple-inputmultiple-output (MIMO) radar in the presence of gain-phase error and mutual coupling error. An auxiliary sensors-based framework is proposed, the matched array measurement of the MIMO radar is formulated as a parallel factor (PARAFAC) model, which links the problem of joint DOD and DOA estimation to PARAFAC decomposition. Thereafter, the DODs and DOAs are obtained via least square strategy. The proposed method is computationally more efficient than the existing reduced-MUSIC method. Besides, it can achieve closed-form solutions for DODs and DOAs, which are paired automatically. Numerical experiments demonstrate the effectiveness of our method.
This paper addresses the problem of direction finding for bistutic MAIO radar in the presence of unknown spatially colored noise. Taking the stationary property of the colored noise into consideration, a covariance di...
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ISBN:
(纸本)9781538668122;9781538668115
This paper addresses the problem of direction finding for bistutic MAIO radar in the presence of unknown spatially colored noise. Taking the stationary property of the colored noise into consideration, a covariance differencing-based method is presented. The proposed method has computational complexity very close to that of ESPRIT. Besides, it can suppress the colored noise without any virtual aperture loss. Therefore, it improves the accuracy of angle estimation compared with the existing de-noising algorithms. Numerical experiments are provided to examine the effectiveness and improvement of our algorithm.
This paper presents a portable 24-GHz multiple-inputmultiple-output (MIMO) radar with 16 transmit (Tx) channels and 16 receive (Rx) channels. The radar is intended for short-range localization and three-dimensional (...
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ISBN:
(纸本)9781538692622
This paper presents a portable 24-GHz multiple-inputmultiple-output (MIMO) radar with 16 transmit (Tx) channels and 16 receive (Rx) channels. The radar is intended for short-range localization and three-dimensional (3-D) imaging by detecting the ranges, azimuth angles, and zenith angles of targets in front of the radar. The radar is capable of two-dimensional (2-D) beamforming achieved using a non-uniformly spaced planar array. A prototype of this 16x16 radar has been built to demonstrate its short-range localization capability.
multiple-inputmultiple-output (MIMO) radars have attracted much attention for their superior ability to enhance a system's performance. In this study, the authors' goal was the study of the spatial multiplexi...
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multiple-inputmultiple-output (MIMO) radars have attracted much attention for their superior ability to enhance a system's performance. In this study, the authors' goal was the study of the spatial multiplexing gain of MIMO radars with widely separated antennas (WS-MIMO), which the authors showed that is equal to the number of unambiguously detectable targets. They obtained this number from two different aspects: first, by defining the ambiguity function of a WS-MIMO radar in the case of multiple targets, suitable for such purpose;Second, by modelling the MIMO radar system with a MIMO wireless channel. They showed that a MIMO radar is indeed a MIMO wireless system communicating the information about the existence of the targets. By such modelling, they could easily make the relation between dual concepts of MIMO radar and MIMO communication, one of which is the multiplexing gain.
For a non-coherent multiple-input multiple-output radar system, the minimum mean square error (MMSE) estimator and maximum a posteriori (MAP) estimator of the target location and velocity, considered random unknown pa...
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For a non-coherent multiple-input multiple-output radar system, the minimum mean square error (MMSE) estimator and maximum a posteriori (MAP) estimator of the target location and velocity, considered random unknown parameters, are formulated and the corresponding posterior Cramer-Rao lower bound (PCRLB) is derived. Moreover, numerical solutions for the proposed MMSE estimator and the PCRLB are obtained by using Monte-Carlo methods because of the absence of closed-form solutions. The numerical results show that the mean square errors (MSEs) of the MMSE estimate and the MAP estimate converge to the corresponding PCRLB as the signal-to-noise ratio (SNR) increases when the number of transmit and receive antennas is sufficiently large. A linear approximation can be used to simplify the MMSE estimation. It is shown in some simulations that the linear approximation of the MMSE estimate is accurate at high SNR values and the SNR needed for accurate approximation can be reduced by increasing the number of antennas employed.
In this paper, the problem of direction-of-arrival (DOA) estimation for monostatic multiple-inputmultiple-output (MIMO) radar with gain-phase errors is addressed, by using a sparse DOA estimation algorithm with fourt...
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In this paper, the problem of direction-of-arrival (DOA) estimation for monostatic multiple-inputmultiple-output (MIMO) radar with gain-phase errors is addressed, by using a sparse DOA estimation algorithm with fourth-order cumulants (FOC) based error matrix estimation. Useful cumulants are designed and extracted to estimate the gain and the phase errors in the transmit array and the receive array, thus a reliable error matrix is obtained. Then the proposed algorithm reduces the gain-phase error matrix to a low dimensional one. Finally, with the updated gain-phase error matrix, the FOC-based reweighted sparse representation framework is introduced to achieve accurate DOA estimation. Thanks to the fourth-order cumulants based gain-phase error matrix estimation, and the reweighted sparse representation framework, the proposed algorithm performs well for both white and colored Gaussian noises, and provides higher angular resolution and better angle estimation performance than reduced-dimension MUSIC (RD-MUSIC), adaptive sparse representation (adaptive-SR) and ESPRIT-based algorithms. Simulation results verify the effectiveness and advantages of the proposed method. (C) 2017 Elsevier Inc. All rights reserved.
In this paper, the direction of arrival (DOA) estimation for noncircular sources in multiple-inputmultipleoutput (MIMO) radar is dealt with by a novel nuclear norm minimization (NNM) framework. The proposed method e...
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In this paper, the direction of arrival (DOA) estimation for noncircular sources in multiple-inputmultipleoutput (MIMO) radar is dealt with by a novel nuclear norm minimization (NNM) framework. The proposed method exploits the noncircular property of signals to extend the data model for doubling the array aperture. Then a block sparse model of the extended data is formulated without the influence of the unknown noncircularity phase, and a novel signal reconstruction algorithm based on nuclear norm minimization is proposed to recover the block-sparse matrix. In addition, a weight matrix based on the reduced dimensional noncircular Capon (RD NC-Capon) spectrum is designed to reweight the nuclear norm minimization for enhancing the sparsity of solution. Finally, the DOA is estimated from the non-zero blocks of the reconstructed matrix. Due to exploiting the extended array aperture and block-sparse information, the proposed method provides superior DOA estimation performance and higher angular resolution. Furthermore, the proposed method has a low sensitivity to the priori information on the number of sources. Simulation results are presented to verify the effectiveness and advantages of the proposed method.
In this paper, a novel unitary parallel factor (U-PARAFAC) algorithm of estimating direction-of-departure (DOD) and direction-of-arrival (DOA) in bistatic multiple-inputmultiple-output (MIMO) radar is proposed. A rea...
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In this paper, a novel unitary parallel factor (U-PARAFAC) algorithm of estimating direction-of-departure (DOD) and direction-of-arrival (DOA) in bistatic multiple-inputmultiple-output (MIMO) radar is proposed. A real-valued tensor signal model is constructed by applying the traditional forward-backward averaging technique. Subsequently, the fact that the real-valued tensor follows a PARAFAC model is proved, thus the subspace-based high-order singular value decomposition (HOSVD) method can be avoided in the subsequent solving process. Furthermore, directly operating the real-valued loading factors instead of the signal subspace, traditional unitary ESPRIT (U-ESPRIT) method is firstly extended to the real-valued PARAFAC model. The new algorithm, which exploits the multidimensional structure and does not require the estimation of signal subspace, having good performance especially at low signal-to-noise ratio (SNR). More attractively, compared with classical tensor methods such as the PARAFAC algorithm and the unitary tensor-ESPRIT algorithm, the U-PARAFAC algorithm still performs well without sacrificing array aperture when targets are highly correlated or closely spaced. Additional angle pair-matching is not required. Simulation results verify the effectiveness of the proposed algorithm. (C) 2017 Elsevier B.V. All rights reserved.
A motion-compensation method that applies sparse reconstruction (SR) to reconstruct the Doppler spectrum of targets based on a random transmission scheme is proposed for time-division multiplexing (TDM) multiple-input...
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A motion-compensation method that applies sparse reconstruction (SR) to reconstruct the Doppler spectrum of targets based on a random transmission scheme is proposed for time-division multiplexing (TDM) multiple-inputmultiple-output (MIMO) radar. Since the random transmission can eliminate the characteristic of periodic time-delay in conventional TDM scheme between transmit cycles, the angle information of a target is not affected by its motion. Therefore, the angle and velocity are no longer coupled with each other and can be estimated separately. This method not only overcome the space-frequency coupling problem but also enhances the unambiguous Doppler interval. Another advantage is that the method is valid even when the estimated target velocity is ambiguous. The results reported here offer the possibility of utilising SR to solve conventional TDM MIMO problems. The effectiveness of the proposed method is demonstrated by experimental results.
Although sparse representation and sparse recovery algorithms for colocated multiple-inputmultipleoutput (MIMO) radar have received much attention, incoherence of the sensing matrix received few discussions. In this...
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Although sparse representation and sparse recovery algorithms for colocated multiple-inputmultipleoutput (MIMO) radar have received much attention, incoherence of the sensing matrix received few discussions. In this paper, we propose adaptive weight matrix design and parameter estimation via sparse modeling to improve the recovery performance for MIMO radar. First, a sparse framework is formulated for the MIMO array with decoupled transmit weight matrix and steering matrix. Next, a two stage method is proposed to optimize the two matrices to improve the DOA estimation performance. Finally, a sparse recovery approach based on l(q) (0 < q <= 1) norm optimization is developed to estimate the unknown target parameters. Furthermore, the algorithm can be iteratively implemented with the obtained closed-form solution for the optimization problem. The angle-amplitude estimation performance is examined by analyzing the Cramer-Rao lower bound (CRLB). Numerical results demonstrate that significant performance improvement has been achieved by the proposed sensing matrix optimization and adaptive weight matrix design approach. (C) 2017 Elsevier B.V. All rights reserved.
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