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Colocated MIMO Radar Waveform-array Joint Optimization for sparse array

SENSORS 2023年第9期23卷 4375页

作者： Yin, Jinrong Ma, Rui Lin, Mingcong Zhou, Shenghua Nanjing Inst Elect Technol Nanjing 210039 Peoples R China Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China

Colocated multiple-input multiple-output (MIMO) radar can transmit a group of distinct waveforms via its colocated transmit antennas and the waveform diversity leads to several advantages in contrast to conventional phased-array radar. The performance depends highly on the degrees available, and element spacing can be deemed as another source of degrees of freedom. In this paper, we study the joint waveform and element spacing optimization problem. A joint waveform and array optimization criterion is proposed to match the transmit beampattern, the suppression range, and the angular sidelobes, under the constraints of minimal element spacing and total array aperture. Meanwhile, the effect of receive beamforming on suppressing mutual correlation between returns from different spatial directions is also incorporated into the optimization criterion. The optimization problem is solved by the sequential quadratic programming algorithm. Numerical results indicate that with more degrees of freedom from array spacings, colocated MIMO radar achieves a better transmit beampattern matching performance and a lower sidelobe level, compared with a fixed half-wavelength spaced array, but the benefits from additional degrees of freedom from array spacing optimization have a limit.

关键词： colocated MIMO radar waveform optimization array optimization sparse array range sidelobe suppression

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Meta-heuristic optimization algorithms for placement of multiple nulls and minimization of side lobe level in quadrant symmetric sparse array antenna

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INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS 2022年第10期35卷 e5149-e5149页

作者： Dutta, Kailash P. Misra, Bitan Mahanti, Gautam K. Natl Inst Technol Dept Elect & Commun Engn Durgapur 713209 India Cambridge Inst Technol Dept Elect & Commun Engn Ranchi Bihar India

The optimization of the non-uniform planar array antenna parameter in order to minimize the signal interference in the electromagnetic environment through null placement is one of the most important areas of investigation in the field of wireless communication. This study deals with an effective method of synthesis of a quadrant symmetric sparse planar array antenna using the novel implementation of the well-known meta-heuristic optimization algorithms, namely, symbiotic organism search (SOS) and moth flame optimization (MFO) algorithms. The objective of this work is to place multiple small and wide nulls at the desired angles and simultaneously minimize the side lobe levels using a nonlinear mathematical approach. Three examples are presented with constraints that include the inter-elemental distance, fixed number of array elements in the aperture, and the aperture size. The radiating antenna array elements are considered to have fixed uniform current distribution. The meta-heuristic optimization approach offers the advantages of avoiding the infeasible solution while finding the best optimal set of element positions to reduce side lobe level in the desired radiation pattern. The radiation pattern characteristics and the computation time associated with each example and each algorithm are recorded and compared for arriving at the conclusion. The superiority of SOS is found in terms of the optimized side lobe levels. At the same time, both algorithms are found to be efficient in positioning the symmetric nulls in desired locations in the radiation pattern successfully. When compared with the published papers, proposed approach yields better results confirming the effectiveness of the performance of these algorithms.

关键词： antenna array synthesis beam forming meta-heuristic optimization minimized sidelobe levels multiple null placements sparse array

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A Study on Capacitive Micromachined Ultrasonic Transducer Periodic sparse array

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MICROMACHINES 2021年第6期12卷 684-684页

作者： Zhang, Tian Zhang, Wendong Shao, Xingling Yang, Yuhua Wang, Zhihao Wu, Yang Pei, Yu North Univ China State Key Lab Dynam Testing Technol Taiyuan 030051 Peoples R China North Univ China Sch Instrument & Elect Natl Key Lab Elect Measurement Technol Taiyuan 030051 Peoples R China

Capacitive micromachined ultrasonic transducer (CMUT) is an ultrasonic transducer based on the microelectromechanical system (MEMS). CMUT elements are easily made into a high-density array, which will increase the hardware complexity. In order to reduce the number of active channels, this paper studies the grating lobes generated by CMUT periodic sparse array (PSA) pairs. Through the design of active element positions in the transmitting and receiving processes, the simulation results of effective aperture and beam patterns show that the common grating lobes (CGLs) generated by the transmit and receive array are eliminated. On the basis of point targets imaging, a CMUT linear array with 256 elements is used to carry out the PSA pairs experiment. Under the same sparse factor (SF), the optimal sparse array configuration can be selected to reduce the imaging artifacts. This conclusion is of great significance for the application of CMUT in three-dimensional ultrasound imaging.

关键词： CMUT sparse array ultrasound imaging MEMS

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Improving performance of direction-of-arrival estimation using sparse array in passive radar

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JOURNAL OF ALGORITHMS & COMPUTATIONAL TECHNOLOGY 2020年第14期14卷 -页

作者： Chen, Geng Tian, Bo Gong, Jian Feng, Cunqian Air Force Engn Univ Xian 710051 Peoples R China

A method based on sparse array is applied to direction-of-arrival estimation of passive radar in this paper to increase the number of resolvable sources and improve the direction-of-arrival estimation performance for coprime array. The virtual symmetric non-uniform linear array of coprime array based on passive radar signal model is introduced. Considering the impact of direct wave, extensive cancellation algorithm is used to cancel the direct wave, with the conventional MUSIC with spatial smoothing algorithm and virtual aperture filling applied on the sparse array of passive radar;the resolution of target is low in the low signal-noise-ratio. To effectively improve the estimation of the target under the low signal-noise-ratio, a noise subspace reconstruction method is proposed. The proposed direction-of-arrival estimation method can improve the direction-of-arrival estimation performance of passive radar. The simulations are provided to demonstrate the effectiveness of the proposed method.

关键词： Direction-of-arrival passive radar sparse array virtual array super resolution

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High-Efficiency Periodic sparse Microstrip array Based on Mutual Coupling

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2013年第4期61卷 1963-1970页

作者： Qu, Shi-Wei Chan, Chi Hou Xia, Ming-Yao Nie, Zaiping Univ Elect Sci & Technol China Sch Elect Engn Chengdu 611731 Peoples R China City Univ Hong Kong Dept Elect Engn Kowloon Hong Kong Peoples R China

In this paper, a novel idea to reduce the number of active elements in a large periodic array is presented and demonstrated firstly by an E-plane microstrip array. High aperture efficiency can be achieved by making use of mutual coupling between array elements, and then the total production cost of the array is greatly decreased by reducing the number of active array elements and associated components. A simple way to control the mutual coupling of the microstrip array is given as an example in this paper. Simulations and measurements show that when the active element spacing is as large as 1.6 lambda(0) (lambda(0) is the free-space wavelength at the operating frequency), a -18.3 dB side lobe level (SLL) and an approximately equal aperture efficiency can be achieved. No obvious performance degradations are found compared to a conventional array with half the element spacing (0.8 lambda(0)) and an identical total size. Then, simulations and measurements of an H-plane sparse array are given based on the same idea, followed by the simulated results of a planar two-dimensional (2-D) one.

关键词： Antenna arrays microstrip antennas mutual coupling sparse array thinned array

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sparse transmit array design for dual-function radar communications by antenna selection

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DIGITAL SIGNAL PROCESSING 2018年 83卷 223-234页

作者： Wang, Xiangrong Hassanien, Aboulnasr Amin, Moeness G. Beihang Univ Sch Elect & Informat Engn Beijing 100191 Peoples R China Wright State Univ Dept Elect Engn Dayton OH 45435 USA Villanova Univ Ctr Adv Commun Villanova PA 19085 USA

Dual-function radar communications (DFRC) systems have recently been proposed to enable the coexistence of radar and wireless communications, which in turn alleviates the increased spectrum congestion crisis. In this paper, we consider the problem of sparse transmit array design for DFRC systems by antenna selection where same or different antennas are assigned to different functions. We consider three different types of DFRC systems which implement different simultaneous beamformers associated with single and different sparse arrays with shared aperture. We utilize the array configuration as an additional spatial degree of freedom (DoF) to suppress the cross-interference and facilitate the cohabitation of the two system functions. It is shown that the use of sparse arrays adds to improved angular resolution with well-controlled sidelobes on DFRC system paradigm. The utilization of sparse arrays in DFRC systems is validated using simulation examples. (C) 2018 Elsevier Inc. All rights reserved.

关键词： sparse array Dual-function radar communications Power pattern Antenna selection

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Efficient Imaging Techniques Using Sub-aperture Matrix Capture and Two-dimensional sparse array

Efficient Imaging Techniques Using Sub-aperture Matrix Captu...

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2014 IEEE Far East Forum on Nondestructive Evaluation/Testing: New Technology & Application Increasingly perfect NDT/E

作者： Yun Yang Jianqiang Guo Xiaorong Gao Jing Li Jianping Peng Biao Zheng Hua Peng Nondestructive Testing Research Center Southwest Jiaotong University

Total focusing method(TFM)is a post-processing algorithm for ultrasonic imaging,usually used for processing linear array *** this paper,TFM is extended to obtain three-dimensional(3D)image based on two-dimensional array ***,it takes a long time to get 3D information from large amount of 2D array data by *** Sub-aperture matrix capture(SMC)and sparse array are taken into account to solve this *** experimental results prove that TFM precisely reconstruct 3D information of defects through the optimized *** a small angle imaging range,SMC can reach the same image quality and the same array performance indicator(API)as full matrix capture(FMC).In addition,it won’t take more than one quarter of the time token by FMC for ultrasonic *** the spurious image is enhanced with the reducing sparseness,the processing time is *** both image quality and real-time imaging,the imaging efficiency might be improved by 50 times through the combination of the two *** paper provides an optional approach to achieve real-time imaging system.

关键词： Total focusing method(TFM) sparse array Sub-aperture matrix capture Imaging efficiency Full matrix capture(FMC)

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Design of 2D sparse array Transducers for Anomaly Detection in Medical Phantoms

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SENSORS 2020年第18期20卷 5370.-5370.页

作者： Li, Xiaotong Gachagan, Anthony Murray, Paul Univ Strathclyde Dept Elect & Elect Engn Glasgow G1 1XW Lanark Scotland

Aperiodic sparse 2D ultrasonic array configurations, including random array, log spiral array, and sunflower array, have been considered for their potential as conformable transducers able to image within a focal range of 30-80 mm, at an operating frequency of 2 MHz. Optimisation of the imaging performance of potential array patterns has been undertaken based on their simulated far field directivity functions. Two evaluation criteria, peak sidelobe level (PSL) and integrated sidelobe ratio (ISLR), are used to access the performance of each array configuration. Subsequently, a log spiral array pattern with -19.33 dB PSL and 2.71 dB ISLR has been selected as the overall optimal design. Two prototype transducers with the selected log spiral array pattern have been fabricated and characterised, one using a fibre composite element composite array transducer (CECAT) structure, the other using a conventional 1-3 composite (C1-3) structure. The CECAT device demonstrates improved coupling coefficient (0.64 to 0.59), reduced mechanical cross-talk between neighbouring array elements (by 10 dB) and improved operational bandwidth (by 16.5%), while the C1-3 device performs better in terms of sensitivity (similar to 50%). Image processing algorithms, such as Hough transform and morphological opening, have been implemented to automatically detect and dimension particles located within a fluid-filled tube structure, in a variety of experimental scenarios, including bespoke phantoms using tissue mimicking material. Experiments using the fabricated CECAT log spiral 2D array transducer demonstrated that this algorithmic approach was able to detect the walls of the tube structure and stationary anomalies within the tube with a precision of similar to 0.1 mm.

关键词： sparse array ultrasonic transducer particle detection

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Near-Field Synthetic Spectrum Imaging Algorithm Based on Single-Frequency sparse MIMO array

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IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS 2019年第9期18卷 1946-1950页

作者： Wang, Hui Wu, Shiyou Li, Chao Liu, Xiaojun Fang, Guangyou Univ Chinese Acad Sci Beijing 100039 Peoples R China Chinese Acad Sci Key Lab Electromagnet Radiat & Sensing Technol Beijing 100190 Peoples R China

This letter presents a two-dimensional near-field synthetic spectrum imaging algorithm based on a single-frequency sparse multiple-input-multiple-output (MIMO) array. By using an especially defined backward spreading function, the proposed algorithm migrates the scattered wave field under different illuminations. A synthetic spectrum can be obtained by synthesizing the spectrums of these migration results and then interpreted to the final reconstruction. The migration processing enables the algorithm to adapt to arbitrary apertures. Meanwhile, the influences of the limited aperture, the spreading loss, and the wavefront curvature in the near field are considered and compensated. High processing speed is achieved by using a large interpixel spacing during the migration processing and by the fast Fourier transform in the frequency-wavenumber (f-w) domain. Simulations and experiments are carried out, and the results demonstrate both the high-computational efficiency and the high flexibility for arbitrary sparse MIMO array apertures.

关键词： Backward migration multiple-input-multiple-output (MIMO) near-field imaging sparse array synthetic spectrum

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sparse linear array synthesis using artificial neural network and nonconvex optimization

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MICROWAVE AND OPTICAL TECHNOLOGY LETTERS 2024年第5期66卷 e34155-e34155页

作者： Li, Hanyu Zhou, Haijing Liao, Cheng Southwest Jiaotong Univ Sch Phys Sci & Technol Chengdu Peoples R China Inst Appl Phys & Computat Math Dept 1 Beijing Peoples R China 2 Feng Hao Dong Lu Rd Beijing Peoples R China

The concept of sparse array synthesis has attracted considerable attention due to its potential to reduce hardware costs in array design and enhance the efficiency of array aperture utilization. In contrast to conventional artificial neural networks (ANNs), a more efficient encoder-decoding ANN framework is proposed in this letter for designing sparse linear arrays. The decoder is pretrained with a randomly generated training set, enabling its ability to rapidly predictiction of far-field patterns. This process considers the actual coupling effect among the antenna elements. The output of the encoder is used as the input of the decoder to synthesize the sparse arrays by providing the desired pattern to the encoder. During the training process, a novel lp ${l}_{p}$-norm (0sparse arrays, including large-scale arrays. In comparison to existing algorithms, our proposed method exhibits superior computational efficiency and predicted accuracy with fewer elements.

关键词： artificial neural networks linear arrays nonconvex optimization sparse array

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