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Computer Science, Information Systems
Xinghua Jia, Chengzhuo Shi
Summary: This paper studies joint source and relay beamforming optimization and time allocation for a wireless powered multi-relay multi-user network. The proposed joint optimization scheme outperforms other schemes in terms of maximizing the minimum rate among the users.
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Automation & Control Systems
Keyuan Hu, Wenxin Xiong, Yuwei Wang, Zhang-Lei Shi, Ge Cheng, Hing Cheung So, Zhi Wang
Summary: This contribution studies the localization technique of passive elliptic positioning (PEP) with unknown transmitter locations, which has great potential applicability. The challenge of outliers in complex real-world environments is addressed by using the concept of robust statistics. A differentiable cost function with outlier-resistance replaces the pound 2 loss in the traditional nonlinear least squares formulation. The neurodynamic approach of Lagrange programming neural network is adopted to efficiently solve the resulting nonconvex statistically robustified PEP problem. Simulations and experiments demonstrate the performance superiority of the proposed method over competitors.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2023)
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Computer Science, Theory & Methods
Lu Lv, Zan Li, Haiyang Ding, Naofal Al-Dhahir, Jian Chen
Summary: This paper investigates covert wireless communication in a multi-antenna relay network, proposing two relay beamforming schemes to ensure reception reliability at the destination while deliberately degrading the source's detection capability. The analytical expressions for the minimum detection error probability achieved by each scheme under the worst-case covert communication scenario are derived, and an optimization problem is formulated to maximize the covert rate with the derived results as the covertness constraint. Simulation results confirm the accuracy of the derived analytical results and quantify the communication covertness enhancement of the proposed schemes. The study shows that the MRT beamforming scheme offers a higher covert rate than the random beamforming scheme, especially in loose covertness constraints or with an increased number of relay antennas.
IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY
(2022)
Article
Engineering, Electrical & Electronic
Zhi Mao, Fengye Hu, Wen Wu, Huaqing Wu, Xuemin Shen
Summary: This paper studies a UAV-assisted wireless powered sensor network (WPSN) where multiple types of sensor nodes can harvest radio-frequency energy from the UAV and transmit sensing data. A joint distributed beamforming (DBF) and backscattering scheme is proposed to improve received signal strength. The problem is formulated as a sum-throughput maximization problem and a two-step algorithm is proposed to solve it.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Junwei Zhou, Hongbin Li, Wei Cui
Summary: This study focuses on the joint design of transmit and receive beamforming in MIMO systems, utilizing a biquadratic optimization approach to accelerate convergence and improve beamforming performance. Simulation results demonstrate that the proposed method reduces computational complexity significantly and provides better beamforming solutions compared to the conventional T-R iteration method.
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Operations Research & Management Science
Cheng Lu, Jitao Ma, Zhibin Deng, Wenxun Xing
Summary: In this paper, a semidefinite relaxation based branch-and-bound algorithm is proposed for solving the unit-modulus constrained complex quadratic programming problem, which is widely applicable in signal processing and wireless communications. The research is motivated by the potential application of the magnitude least-square problem with the block-arrow sparsity pattern. The authors discuss the reduction of worst-case complexity of the proposed algorithm by exploiting this special sparsity pattern. Numerical results are presented to demonstrate the effectiveness of the algorithm.
JOURNAL OF GLOBAL OPTIMIZATION
(2023)
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Engineering, Electrical & Electronic
Huiping Huang, Hing Cheung So, Abdelhak M. Zoubir
Summary: This paper presents a sparse array design algorithm for adaptive beamforming, which achieves excellent performance and computational complexity.
IEEE TRANSACTIONS ON SIGNAL PROCESSING
(2023)
Article
Engineering, Electrical & Electronic
Thierry Chonavel, Abdeldjalil Aissa-El-Bey, Zahran Hajji
Summary: In this paper, we address the problem of recovering block-sparse structures in a linear regression context. We propose an iterative block cyclic descent algorithm for l(2,0) penalty and prove its convergence. Our approach shows potential benefits compared to l(2,1) or l(2,q) (0 < q <= 1) penalization. We also introduce a momentum approach for accelerated convergence and apply it to sensor positioning in array processing.
Article
Computer Science, Information Systems
Samer Alabed, Ibrahim Mahariq, Mohammad Salman, Mustafa Kuzuoglu
Summary: This article utilizes a low-cost electromagnetic structure to emulate photonic nanojets and improve the efficiency of wireless relay networks. The application of the optimal single-relay selection method achieves full diversity gain with low complexity, and combining smart relays enhances network performance by achieving the highest coding and diversity gain. The proposed technique outperforms the best known single relay selection technique and the BER expressions from theoretical analysis match those obtained from simulations.
CMC-COMPUTERS MATERIALS & CONTINUA
(2021)
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Engineering, Electrical & Electronic
Manlin Wang, Zhen Xu, Bin Xia, Yinghong Guo, Zhiyong Chen
Summary: This paper proposes a coordinated direct and relay transmission (CDRT) scheme utilizing a multi-antenna relay to maximize the covert rate. A semidefinite relaxation based line search method is proposed to obtain the globally optimal beamforming vectors that balance the direct and the relay link to satisfy the covertness requirements and achieve the maximum covert rate. Numerical results demonstrate the superiority and robustness of the proposed CDRT scheme, especially when the warder-related links are highly correlated. Additionally, the CDRT scheme outperforms the cooperative jammer assisted covert system even with high transmission power due to joint beamforming.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Tong Han, David J. Hill
Summary: The paper addresses the dispatch of virtual inertia and damping among inverters in the transmission network for future power grids interfaced with 100% renewable energy. It formulates the problem as a nonlinear program and uses semi-definite programming relaxation to tackle non-convexity, followed by a feasibility-embedded distributed approach under the ADMM framework for solving high dimension and inexactness issues. Numerical simulations demonstrate the proposed method and the necessity of dispatch of virtual inertia and damping in power systems.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2021)
Article
Mathematics, Applied
Jie Wang, Victor Magron, Jean-Bernard Lasserre
Summary: This paper introduces a new hierarchy of semidefinite programming relaxations for polynomial optimization problems, exploiting the sparsity of input polynomials. The novelty lies in involving block-diagonal matrices obtained through an iterative procedure for completing connected components of certain adjacency graphs. The theoretical framework is then applied to compute lower bounds for polynomial optimization problems.
SIAM JOURNAL ON OPTIMIZATION
(2021)
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Engineering, Electrical & Electronic
Ge Yang, Yongsheng Yan, Haiyan Wang, Xiaohong Shen
Summary: This paper proposes an improved time of arrival-based method for localizing sources in wireless sensor networks, taking into account sensor location uncertainty. The nonconvex optimization problem is transformed into a convex one using a semidefinite relaxation technique. Experimental results show that the proposed method improves the accuracy of source localization.
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Engineering, Electrical & Electronic
Ahona Bhattacharyya, Jason M. M. Merlo, Serge R. R. Mghabghab, Anton Schlegel, Jeffrey A. A. Nanzer
Summary: This study demonstrates the effectiveness of distributed microwave multiobjective beamforming near the array using an optimization algorithm and wireless frequency alignment. It shows the feasibility of steering signals to locations close to the array in open-loop systems, something that has not been demonstrated before. By applying a traditional far-field beamforming algorithm to a set of wirelessly syntonized distributed antennas, the researchers achieved multiobjective beamforming at 0.9 GHz using software-defined radios, enabling the steering of either two beams or one beam and one null. This work proves the feasibility of a crucial component in future distributed beamforming systems, which, when combined with other coordination technologies, will enable coherent beamforming in widely distributed wireless systems.
IEEE MICROWAVE AND WIRELESS TECHNOLOGY LETTERS
(2023)
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Engineering, Electrical & Electronic
Xinwei Guo, Minmin Yuan, Yuxuan Ke, Chengshi Zheng, Xiaodong Li
Summary: This paper proposes a novel distributed node-specific block-diagonal linearly constrained minimum variance beamformer, and reduces computational complexity using the Sherman-Morrison-Woodbury formula. The beamformer effectively handles signal transmission and errors without increasing node complexity.
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(2015)
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(2014)
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Eva Lagunas, Moeness G. Amin, Fauzia Ahmad, Montserrat Najar
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(2013)
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(2014)
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Luis Blanco, Montse Najar
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(2012)
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Luca Reggiani, Jocelyn Fiorina, Sinan Gezici, Simone Morosi, Montse Najar
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Genis Floriach, Montse Najar, Monica Navarro
2017 25TH EUROPEAN SIGNAL PROCESSING CONFERENCE (EUSIPCO)
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Luis Blanco, Montse Najar
2015 23RD EUROPEAN SIGNAL PROCESSING CONFERENCE (EUSIPCO)
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Luis Blanco, Montse Najar
2014 11TH INTERNATIONAL SYMPOSIUM ON WIRELESS COMMUNICATIONS SYSTEMS (ISWCS)
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Jordi Serra, Montse Najar
2013 PROCEEDINGS OF THE 21ST EUROPEAN SIGNAL PROCESSING CONFERENCE (EUSIPCO)
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Eva Lagunas, Moeness G. Amin, Fauzia Ahmad, Montse Najar
2012 PROCEEDINGS OF THE 20TH EUROPEAN SIGNAL PROCESSING CONFERENCE (EUSIPCO)
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2012 IEEE STATISTICAL SIGNAL PROCESSING WORKSHOP (SSP)
(2012)
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Eva Lagunas, Moeness G. Amin, Fauzia Ahmad, Montse Najar
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(2012)