no code implementations • 14 Jun 2025 • Amarilton L. Magalhães, André L. F. de Almeida, A. Lee Swindlehurst
Dynamic metasurface antennas (DMAs) are emerging as a promising technology to enable energy-efficient, large array-based multi-antenna systems.
no code implementations • 26 May 2025 • Cen Liu, Xiangyun Zhou, Nan Yang, Salman Durrani, A. Lee Swindlehurst
To this end, we consider secure communications through the creation of a virtual protected zone using a full-duplex legitimate receiver.
no code implementations • 18 May 2025 • Huan Huang, Hongliang Zhang, Yi Cai, Dusit Niyato, A. Lee Swindlehurst, Zhu Han
Then, we define the detection error probabilities, i. e., the false alarm rate (FAR) and the missed detection rate (MDR), as the monitoring performance metrics for Willie's detections, and the signal-to-jamming-plusnoise ratio (SJNR) as a communication performance metric for the covert transmissions between Alice and Bob.
no code implementations • 27 Apr 2025 • Qianglong Dai, Yong Zeng, Huizhi Wang, Changsheng You, Chao Zhou, Hongqiang Cheng, Xiaoli Xu, Shi Jin, A. Lee Swindlehurst, Yonina C. Eldar, Robert Schober, Rui Zhang, Xiaohu You
Integrated sensing and communication (ISAC) is one of the key usage scenarios for future sixth-generation (6G) mobile communication networks, where communication and sensing (C&S) services are simultaneously provided through shared wireless spectrum, signal processing modules, hardware, and network infrastructure.
no code implementations • 19 Apr 2025 • Ly V. Nguyen, Rang Liu, Nhan Thanh Nguyen, Markku Juntti, Björn Ottersten, A. Lee Swindlehurst
We refer to this as symmetric-rotation invariance, upon which we develop low-complexity yet efficient DFRC signal design algorithms.
no code implementations • 9 Apr 2025 • Peishi Li, Ming Li, Rang Liu, Qian Liu, A. Lee Swindlehurst
In this paper, we propose adaptive resource allocation strategies for OFDM-ISAC systems to achieve optimal trade-offs between diverse sensing requirements and communication quality-of-service (QoS).
no code implementations • 24 Mar 2025 • Jiacheng Yao, Wei Shi, Wei Xu, Zhaohui Yang, A. Lee Swindlehurst, Dusit Niyato
To facilitate the targeted optimization, we propose a dynamic Byzantine identification method using historical reputation based on ZTA.
no code implementations • 18 Mar 2025 • Rang Liu, Ming Li, A. Lee Swindlehurst
Building on this, we formulate a joint optimization framework for transmit beamforming and dynamic array partitioning to minimize the derived BCRBs for direction-of-arrival (DOA) estimation.
no code implementations • 15 Mar 2025 • Peishi Li, Ming Li, Rang Liu, Qian Liu, A. Lee Swindlehurst
Integrated sensing and communication (ISAC) is a pivotal enabler for next-generation wireless networks.
no code implementations • 7 Mar 2025 • Qingjie Wu, Beixiong Zheng, Guangchi Zhang, Derrick Wing Kwan Ng, A. Lee Swindlehurst
Compared to traditional electromagnetic stealth (ES) materials, which are effective only within specific frequencies and orientations, intelligent reflecting surface (IRS) technology introduces a novel paradigm for achieving dynamic and adaptive ES by adapting its reflection pattern in real time to neutralize radar probing signals echoed back from the target.
no code implementations • 8 Feb 2025 • Liuchang Zhuo, Cunhua Pan, Hong Ren, Ruisong Weng, Shi Jin, A. Lee Swindlehurst, Jiangzhou Wang
Based on the observation that the overall cascaded MIMO channel can be decomposed into multiple sub-channels, the cascaded channel for a typical user is estimated in Stage II.
no code implementations • 3 Dec 2024 • Kenneth Benício, Fazal-E-Asim, Bruno Sokal, André L. F. de Almeida, Behrooz Makki, Gabor Fodor, A. Lee Swindlehurst
We study a monostatic multiple-input multiple-output sensing scenario assisted by a reconfigurable intelligent surface using tensor signal modeling.
no code implementations • 25 Nov 2024 • Nhan Thanh Nguyen, Ly V. Nguyen, Nir Shlezinger, Yonina C. Eldar, A. Lee Swindlehurst, Markku Juntti
We first derive closed-form expressions for the gradients of the communications sum rate and sensing beampattern error with respect to the analog and digital precoders.
no code implementations • 23 Nov 2024 • Jiaqi Xu, Haoyu Wang, Rang Liu, Josef A. Nossek, A. Lee Swindlehurst
In contrast to conventional RIS, the scattering matrix of a non-reciprocal RIS (NR-RIS) is non-symmetric, leading to differences in the uplink and the downlink components of NR-RIS cascaded channels.
no code implementations • 16 Nov 2024 • Nhan Thanh Nguyen, Van-Dinh Nguyen, Hieu V. Nguyen, Hien Quoc Ngo, A. Lee Swindlehurst, Markku Juntti
Furthermore, we devise a power allocation strategy based on successive convex approximation to maximize the communications rate while guaranteeing the CRLB constraints and transmit power budget.
no code implementations • 31 Oct 2024 • Rang Liu, A. Lee Swindlehurst, Ming Li
This paper presents a novel parametric scattering model (PSM) for sensing extended targets in integrated sensing and communication (ISAC) systems.
no code implementations • 30 Oct 2024 • Ly V. Nguyen, Junil Choi, Bjorn Ottersten, A. Lee Swindlehurst
In this paper, we consider the precoding problem in multi-user multiple-input single-output (MISO) systems, incorporating channel coding into the design.
no code implementations • 30 Oct 2024 • Zizhou Zheng, Huan Huang, Hongliang Zhang, A. Lee Swindlehurst
Dual-polarized (DP) multiple-input-multiple-output (MIMO) systems have been widely adopted in commercial mobile wireless communications.
no code implementations • 16 Oct 2024 • Rang Liu, Ming Li, Qian Liu, A. Lee Swindlehurst
Integrated sensing and communication has been identified as an enabling technology for forthcoming wireless networks.
no code implementations • 10 Oct 2024 • Mianyi Zhang, Yunlong Cai, Jiaqi Xu, A. Lee Swindlehurst
Specifically, we first design a deep neural network (DNN) to learn the near-field codebook.
no code implementations • 4 Oct 2024 • Toan-Van Nguyen, Sajjad Nassirpour, Italo Atzeni, Antti Tolli, A. Lee Swindlehurst, Duy H. N. Nguyen
The effects of the steering angle of the $\Sigma\Delta$ architecture, the number of ADC resolution bits, and the number of antennas and users are also extensively analyzed.
no code implementations • 26 Sep 2024 • Mengyuan Ma, Nhan Thanh Nguyen, Italo Atzeni, A. Lee Swindlehurst, Markku Juntti
Low-resolution analog-to-digital converters (ADCs) have emerged as an efficient solution for massive multiple-input multiple-output (MIMO) systems to reap high data rates with reasonable power consumption and hardware complexity.
no code implementations • 11 Sep 2024 • Lu Liu, Rang Liu, Ly V. Nguyen, A. Lee Swindlehurst
This paper focuses on precoding design in multi-antenna systems with improper Gaussian interference (IGI), characterized by correlated real and imaginary parts.
no code implementations • 3 Sep 2024 • Gal Ben Itzhak, Miguel Saavedra-Melo, Benjamin Bradshaw, Ender Ayanoglu, Filippo Capolino, A. Lee Swindlehurst
A potential solution to this problem was previously proposed by the authors in which "biasing transmission lines" carrying standing waves are sampled at each RIS location to produce the desired bias voltage for each RIS element.
no code implementations • 18 Jul 2024 • Minhua Ding, Italo Atzeni, Antti Tölli, A. Lee Swindlehurst
We compare the BLMMSE with the optimal minimum mean squared error (MMSE) channel estimator, which is generally non-linear, and we develop a novel framework based on the orthant probability of a multivariate normal distribution to compute the MMSE channel estimate.
no code implementations • 25 Jun 2024 • Peishi Li, Ming Li, Rang Liu, Qian Liu, A. Lee Swindlehurst
In addition, the proposed waveform design achieves target detection and estimation performance close to that achievable by waveforms designed only for radar, which demonstrates the superiority of the proposed SLP-based ISAC approach.
no code implementations • 27 May 2024 • Lifan Xu, Shunqiao Sun, A. Lee Swindlehurst
This approach considerably decreases the data bandwidth requirements for the wireless channel, making it a more feasible and practical solution for automotive radar collaboration.
no code implementations • 12 Apr 2024 • Beixiong Zheng, Xue Xiong, Tiantian Ma, Jie Tang, Derrick Wing Kwan Ng, A. Lee Swindlehurst, Rui Zhang
The ever-increasing reliance on wireless communication and sensing has led to growing concerns over the vulnerability of sensitive information to unauthorized detection and interception.
no code implementations • 11 Apr 2024 • Huan Huang, Hongliang Zhang, Weidong Mei, Jun Li, Yi Cai, A. Lee Swindlehurst, Zhu Han
Moreover, a theoretical analysis is conducted to quantify the impact of DISCO jamming attacks.
no code implementations • 19 Mar 2024 • Xue Xiong, Beixiong Zheng, A. Lee Swindlehurst, Jie Tang, Wen Wu
Electromagnetic wave absorbing material (EWAM) plays an essential role in manufacturing stealth aircraft, which can achieve the electromagnetic stealth (ES) by reducing the strength of the signal reflected back to the radar system.
no code implementations • 26 Jan 2024 • Kequan Zhou, Guangyi Zhang, Yunlong Cai, Qiyu Hu, Guanding Yu, A. Lee Swindlehurst
To tackle this challenge, we introduce a framework called Feature Allocation for Semantic Transmission (FAST), which offers adaptability to channel fluctuations across both spatial and temporal domains.
no code implementations • 11 Jan 2024 • Yuanwei Liu, Chongjun Ouyang, Zhaolin Wang, Jiaqi Xu, Xidong Mu, A. Lee Swindlehurst
Throughout this paper, promising directions are highlighted to inspire future research endeavors in the realm of NFC, underscoring its significance in the advancement of wireless communication technologies.
no code implementations • 7 Dec 2023 • Ly V. Nguyen, A. Lee Swindlehurst
This paper considers an RIS-aided joint D2D and cellular communication system where the RIS is exploited to cancel interference to the D2D links and maximize the minimum signal-to-interference plus noise (SINR) of the device pairs and cellular users.
no code implementations • 4 Dec 2023 • Italo Atzeni, Antti Tölli, Duy H. N. Nguyen, A. Lee Swindlehurst
Enabling communications in the (sub-)THz band will call for massive multiple-input multiple-output (MIMO) arrays at either the transmit- or receive-side, or at both.
1 code implementation • 1 Oct 2023 • Huan Huang, Lipeng Dai, Hongliang Zhang, Chongfu Zhang, Zhongxing Tian, Yi Cai, A. Lee Swindlehurst, Zhu Han
Unlike the extensive research on legitimate IRS-enhanced communications, in this article we present an adversarial IRS-based fully-passive jammer (FPJ).
no code implementations • 20 Sep 2023 • Ly V. Nguyen, A. Lee Swindlehurst
We also perform a detailed spectral efficiency analysis for both the pilot-directed and decision-directed frameworks.
no code implementations • 20 Sep 2023 • Haoyu Wang, Zhu Han, A. Lee Swindlehurst
While reconfigurable intelligent surface (RIS) technology has been shown to provide numerous benefits to wireless systems, in the hands of an adversary such technology can also be used to disrupt communication links.
no code implementations • 30 Aug 2023 • Huan Huang, Lipeng Dai, Hongliang Zhang, Zhongxing Tian, Yi Cai, Chongfu Zhang, A. Lee Swindlehurst, Zhu Han
Numerical results are also presented to evaluate the effectiveness of the proposed anti-jamming precoder against the DIRS-based FPJs and the feasibility of the designed data frame used by the legitimate AP to estimate the statistical characteristics.
no code implementations • 7 Aug 2023 • Zichao Xiao, Rang Liu, Ming Li, Qian Liu, A. Lee Swindlehurst
The proposed joint estimation algorithm can achieve larger signal-to-noise-ratio (SNR) processing gains and higher resolution by fully exploiting the echo signals and jointly estimating the angle-range-velocity information.
no code implementations • 7 Jul 2023 • Huan Huang, Hongliang Zhang, Yi Cai, A. Lee Swindlehurst, Zhu Han
Emerging intelligent reflecting surfaces (IRSs) significantly improve system performance, while also pose a huge risk for physical layer security.
no code implementations • 28 Jun 2023 • Changsheng You, Yunpu Zhang, Chenyu Wu, Yong Zeng, Beixiong Zheng, Li Chen, Linglong Dai, A. Lee Swindlehurst
Extremely large-scale arrays (XL-arrays) have emerged as a promising technology to achieve super-high spectral efficiency and spatial resolution in future wireless systems.
no code implementations • 5 May 2023 • Vaibhav Kumar, Marwa Chafii, A. Lee Swindlehurst, Le-Nam Tran, Mark F. Flanagan
Integrated sensing and communication (ISAC) is expected to be offered as a fundamental service in the upcoming sixth-generation (6G) communications standard.
no code implementations • 20 Mar 2023 • Ly V. Nguyen, Lu Liu, Nguyen Linh-Trung, A. Lee Swindlehurst
While block-wise processing (BWP) can effectively address the inter-symbol-interference (ISI) in frequency-selective fading channels, its computational complexity and processing delay can be too high for practical implementation.
no code implementations • 1 Feb 2023 • Huan Huang, Ying Zhang, Hongliang Zhang, Yi Cai, A. Lee Swindlehurst, Zhu Han
A theoretical analysis of the proposed DIRS-based FPJ that provides an evaluation of the DIRS-based jamming attacks is derived.
1 code implementation • 26 Jan 2023 • Rang Liu, Ming Li, Qian Liu, A. Lee Swindlehurst
Two optimization problems are formulated for maximizing the achievable sum-rate of the multi-user communications under an SNR constraint for target detection or a CRB constraint for parameter estimation, the transmit power budget, and the unit-modulus constraint of the RIS reflection coefficients.
no code implementations • 20 Jan 2023 • Lu Liu, Christos Masouros, A. Lee Swindlehurst
This paper focuses on designing robust symbol-level precoding (SLP) in an overlay cognitive radio (CR) network, where the primary and secondary networks transmit signals concurrently.
no code implementations • 15 Aug 2022 • Zhendong Peng, Gui Zhou, Cunhua Pan, Hong Ren, A. Lee Swindlehurst, Petar Popovski, Gang Wu
Specifically, in Stage I, the channel state information (CSI) of a typical user is estimated.
1 code implementation • 4 Aug 2022 • Renjie Xie, Wei Xu, Jiabao Yu, Aiqun Hu, Derrick Wing Kwan Ng, A. Lee Swindlehurst
Deep learning (DL) applied to a device's radio-frequency fingerprint~(RFF) has attracted significant attention in physical-layer authentication due to its extraordinary classification performance.
no code implementations • 17 Jun 2022 • Rang Liu, Ming Li, Honghao Luo, Qian Liu, A. Lee Swindlehurst
Integrated sensing and communication (ISAC) is emerging as a key enabler to address the growing spectrum congestion problem and satisfy increasing demands for ubiquitous sensing and communication.
no code implementations • 23 May 2022 • Duy H. N. Nguyen, Italo Atzeni, Antti Tölli, A. Lee Swindlehurst
In this paper, we build upon variational Bayes (VB) inference to design low-complexity multiuser detection algorithms for massive MIMO systems.
no code implementations • 11 Apr 2022 • Ly V. Nguyen, Nhan T. Nguyen, Nghi H. Tran, Markku Juntti, A. Lee Swindlehurst, Duy H. N. Nguyen
Massive multiple-input multiple-output (MIMO) is a key technology for emerging next-generation wireless systems.
no code implementations • 1 Mar 2022 • Rang Liu, Ming Li, A. Lee Swindlehurst
In this paper, we investigate the potential of employing reconfigurable intelligent surface (RIS) in integrated sensing and communication (ISAC) systems.
no code implementations • 2 Feb 2022 • Ender Ayanoglu, Filippo Capolino, A. Lee Swindlehurst
Reconfigurable Intelligent Surfaces (RISs) are programmable metasurfaces that can adaptively steer received electromagnetic energy in desired directions by employing controllable phase shifting cells.
no code implementations • 11 Dec 2021 • Cunhua Pan, Gui Zhou, Kangda Zhi, Sheng Hong, Tuo Wu, Yijin Pan, Hong Ren, Marco Di Renzo, A. Lee Swindlehurst, Rui Zhang, Angela Yingjun Zhang
In the past as well as present wireless communication systems, the wireless propagation environment is regarded as an uncontrollable black box that impairs the received signal quality, and its negative impacts are compensated for by relying on the design of various sophisticated transmission/reception schemes.
no code implementations • 11 Aug 2021 • Rang Liu, Ming Li, Qian Liu, A. Lee Swindlehurst
In this paper, we consider multi-input multi-output (MIMO) DFRC systems and focus on transmit beamforming designs to provide both radar sensing and multi-user communications.
1 code implementation • 10 Aug 2021 • Renjie Xie, Wei Xu, Yanzhi Chen, Jiabao Yu, Aiqun Hu, Derrick Wing Kwan Ng, A. Lee Swindlehurst
To enable the discrimination of RFF from both known and unknown devices, we propose a new end-to-end deep learning framework for extracting RFFs from raw received signals.
no code implementations • 26 Jul 2021 • Ly V. Nguyen, Duy H. N. Nguyen, A. Lee Swindlehurst
In this paper, we propose a deep learning framework for channel estimation, data detection, and pilot signal design to address the nonlinearity in such systems.
no code implementations • 28 Jun 2021 • Gui Zhou, Cunhua Pan, Hong Ren, Petar Popovski, A. Lee Swindlehurst
In the first coherence block, we propose a two-phase channel estimation method, in which the cascaded channel of one typical user is estimated in Phase I based on the linear correlation among cascaded paths, while the cascaded channels of other users are estimated in Phase II by utilizing the partial CSI of the common base station (BS)-RIS channel obtained in Phase I.
no code implementations • 1 May 2021 • Nhan Thanh Nguyen, Ly V. Nguyen, Thien Huynh-The, Duy H. N. Nguyen, A. Lee Swindlehurst, Markku Juntti
Reconfigurable intelligent surface (RIS) technology has recently emerged as a spectral- and cost-efficient approach for wireless communications systems.
no code implementations • 9 Nov 2020 • Cunhua Pan, Hong Ren, Kezhi Wang, Jonas Florentin Kolb, Maged Elkashlan, Ming Chen, Marco Di Renzo, Yang Hao, Jiangzhou Wang, A. Lee Swindlehurst, Xiaohu You, Lajos Hanzo
Reconfigurable intelligent surfaces (RISs) or intelligent reflecting surfaces (IRSs), are regarded as one of the most promising and revolutionizing techniques for enhancing the spectrum and/or energy efficiency of wireless systems.
no code implementations • 5 Nov 2020 • Ly V. Nguyen, Duy H. N. Nguyen, A. Lee Swindlehurst
Low-resolution analog-to-digital converters (ADCs) have been considered as a practical and promising solution for reducing cost and power consumption in massive Multiple-Input-Multiple-Output (MIMO) systems.
no code implementations • 19 Oct 2020 • Qingqing Wu, Jie Xu, Yong Zeng, Derrick Wing Kwan Ng, Naofal Al-Dhahir, Robert Schober, A. Lee Swindlehurst
On the other hand, providing such communication services simultaneously for both UAV and ground users poses new challenges due to the need for ubiquitous 3D signal coverage as well as the strong air-ground network interference.
no code implementations • 9 Aug 2020 • Ly V. Nguyen, A. Lee Swindlehurst, Duy H. N. Nguyen
Based on the reformulated ML detection problem, we propose a model-driven deep neural network-based (DNN-based) receiver, whose performance is comparable with an existing support vector machine-based receiver, albeit with a much lower computational complexity.
no code implementations • 29 Jul 2020 • Rang Liu, Ming Li, Qian Liu, A. Lee Swindlehurst, Qingqing Wu
Intelligent reflecting surfaces (IRS) have been proposed as a revolutionary technology owing to its capability of adaptively reconfiguring the propagation environment in a cost-effective and hardware-efficient fashion.
no code implementations • 9 Jun 2020 • Zhangjie Peng, Zhenkun Zhang, Cunhua Pan, Li Li, A. Lee Swindlehurst
Low-cost passive intelligent reflecting surfaces (IRSs) have recently been envisioned as a revolutionary technology capable of reconfiguring the wireless propagation environment through carefully tuning reflection elements.
no code implementations • 15 May 2020 • Shilpa Rao, Gonzalo Seco-Granados, Hessam Pirzadeh, Josef A. Nossek, A. Lee Swindlehurst
We consider channel estimation for an uplink massive multiple-input multiple-output (MIMO) system where the base station (BS) uses an array with low-resolution (1-2 bit) analog-to-digital converters and a spatial Sigma-Delta ($\Sigma\Delta$) architecture to shape the quantization noise away from users in some angular sector.