The DOA estimation method of coherent signals based on periodical coding metasurface is proposed. After periodical coding, the DOA information of incident signals in the time domain is represented as the amplitude and phase information at different frequency points in the frequency domain. Finite time Fourier transform (FTFT) is performed on the received signal and appropriate frequency points are selected to reconstruct the frequency domain snapshot, then pattern smoothing (PS) technique is applied to execute DOA estimation. Compared with conventional DOA estimation methods, the proposed method has two main advantages: one is that only a single receiving channel is needed to avoid the appearance of channel mismatch errors, the other is that it can process with multiple coherent signals. The performance curves of the proposed method are analyzed under different conditions and compared with existing methods. Simulation results show the effectiveness of the proposed method.
This paper proposes a compressed sensing-based high-resolution direction-of-arrival estimation method called gradient orthogonal matching pursuit (GOMP). It contains two main steps: a sparse coding approximation step using the well-known OMP method and a sequential iterative refinement step using a newly proposed gradient-descent method. To enhance the recoverability, we further propose an efficient projection matrix design method, which considers the constant modulus constraints imposed by the projection matrix hardware components. Simulation results show the effectiveness of the proposed met…
This paper is concerned with estimating unknown multi-dimensional frequencies from linear compressive measurements. This is accomplished by employing the recently proposed atomic norm minimization framework to recover these frequencies under a sparsity prior without imposing any grid restriction on these frequencies. To this end, we give a rigorous derivation of an iterative scheme called alternating direction of multipliers method, which is able to incorporate multiple compressive snapshots from a multi-dimensional superposition of complex harmonics. The key result here is how to formulate th…
Self-Calibration DOA Estimation for Movable Antenna Systems with Antenna Position Errors
Nanjing University of Science and Technology（南京理工大学）；Qian Xuesen College, Nanjing University of Science and Technology（南京理工大学钱学森学院）；Seoul National University（首尔大学）
DOA Estimation for Low-Altitude Networks: HAD Architectures, Methods, and Challenges
Ningbo University（宁波大学）；City University of Hong Kong（香港城市大学）；Ningbo University of Technology（宁波工程学院）；Xidian University（西安电子科技大学）；Southwest Jiaotong University（西南交通大学）；Hong Kong Metropolitan University（香港都会大学）
Low-Complexity Gridless Single-Snapshot DoA Estimation via Truncated Hankel Newton-MUSIC
The Hong Kong University of Science and Technology（香港科技大学）；Southern University of Science and Technology（南方科技大学）；The University of British Columbia（不列颠哥伦比亚大学）
Bistatic Integrated Sensing and Communications with Flexible Intelligent Metasurfaces
School of Computer Science and Engineering, Constructor University, Bremen, Germany（德国不来梅康斯坦茨大学计算机科学与工程学部）；School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore（新加坡南洋理工大学电气与电子工程学院）
Reconfigurable Intelligent Surfaces (RISs) are envisioned to play a key role in future wireless communications, enabling programmable radio propagation environments. They are usually considered as nearly passive planar structures that operate as adjustable reflectors, giving rise to a multitude of implementation challenges, including an inherent difficulty in estimating the underlying wireless channels. In this paper, we propose the concept of Hybrid RISs (HRISs), which do not solely reflect the impinging waveform in a controllable fashion, but are also capable of sensing and processing a port…
Recently, compressive antenna arrays have been considered for DoA estimation with reduced hardware complexity. By utilizing compressive sensing, such arrays employ a linear combining network to combine signals from a larger set of antenna elements in the analog RF domain. In this paper, we develop a design approach based on the minimization of error between spatial correlation function (SCF) of the compressive and the uncompressed array resulting in the estimation performance of the two arrays to be as close as possible. The proposed design is based on grid-free stochastic gradient descent (SG…
In this paper, we study the problem of joint wideband spectrum sensing and direction-of-arrival (DoA) estimation in a sub-Nyquist sampling framework. Specifically, considering a scenario where a few uncorrelated narrowband signals spread over a wide (say, several GHz) frequency band, our objective is to estimate the carrier frequencies and the DoAs associated with the narrowband sources, as well as reconstruct the power spectra of these narrowband signals. To overcome the sampling rate bottleneck for wideband spectrum sensing, we propose a new phased-array based sub-Nyquist sampling architectu…
With the introduction of shared spectrum sensing and beam-forming based multi-antenna transceivers, 5G networks demand spectrum sensing to identify opportunities in time, frequency, and spatial domains. Narrow beam-forming makes it difficult to have spatial sensing (direction-of-arrival, DoA, estimation) in a centralized manner, and with the evolution of paradigms such as artificial intelligence of Things (AIOT), ultra-reliable low latency communication (URLLC) services and distributed networks, intelligence for edge devices (Edge-AI) is highly desirable. It helps to reduce the data-communicat…
Joint Shape-Position Optimization Enhanced 2D DOA Estimation in Movable Antenna Systems
Key Laboratory of Near-Range RF Sensing ICs and Microsystems (NJUST), Ministry of Education, School of Electronic and Optical Engineering, Nanjing University of Science and Technology（南京理工大学电子与光学工程学院近程射频感知集成电路与微系统教育部重点实验室）；Qian Xuesen College, Nanjing University of Science and Technology（南京理工大学钱学森学院）
Optimizing Dynamic Metasurface Antenna Configurations for Direction-of-Arrival and Polarization Estimation Using an Experimentally Calibrated Multiport-Network Model
Univ Rennes, CNRS, IETR - UMR 6164（雷恩大学）；Department of Electronics and Nanoengineering, Aalto University（阿尔托大学）
Robust Quantum-MUSIC for DoA Estimation Using Rydberg Atomic Receiver Arrays
Indian Institute of Technology (IIT) Delhi（印度理工学院德里分校）；Bharti School of Telecommunication Technology and Management, IIT Delhi（印度理工学院德里分校电信技术与管理学院）；University of Melbourne（墨尔本大学）
Using RF signals for wireless sensing has gained increasing attention. However, due to the unwanted multi-path fading in uncontrollable radio environments, the accuracy of RF sensing is limited. Instead of passively adapting to the environment, in this paper, we consider the scenario where an intelligent metasurface is deployed for sensing the existence and locations of 3D objects. By programming its beamformer patterns, the metasurface can provide desirable propagation properties. However, achieving a high sensing accuracy is challenging, since it requires the joint optimization of the beamfo…
In the practical radar with multiple antennas, the antenna imperfections degrade the system performance. In this paper, the problem of estimating the direction of arrival (DOA) in multiple-input and multiple-output (MIMO) radar system with unknown mutual coupling effect between antennas is investigated. To exploit the target sparsity in the spatial domain, the compressed sensing (CS)-based methods have been proposed by discretizing the detection area and formulating the dictionary matrix, so an \emph{off-grid} gap is caused by the discretization processes. In this paper, different from the pre…
Metasurfaces constitute effective media for manipulating and transforming impinging EM waves. Related studies have explored a series of impactful MS capabilities and applications in sectors such as wireless communications, medical imaging and energy harvesting. A key-gap in the existing body of work is that the attributes of the EM waves to-be-controlled (e.g., direction, polarity, phase) are known in advance. The present work proposes a practical solution to the EM wave sensing problem using the intelligent and networked MS counterparts-the HyperSurfaces (HSFs), without requiring dedicated fi…
