Physical Communication最新文献_第10页

Measurement of path loss in wireless channels assisted by MIM-based anomalous reflection metasurface at 230–330 GHz 基于mimm的230-330 GHz异常反射超表面辅助无线信道路径损耗测量

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-15 DOI: 10.1016/j.phycom.2025.102772

Wenyi Zhang, Ziqi Liu, Yunchuan Liu, Hongcheng Yang, Cunlin Zhang, Jingsuo He

{"title":"Measurement of path loss in wireless channels assisted by MIM-based anomalous reflection metasurface at 230–330 GHz","authors":"Wenyi Zhang, Ziqi Liu, Yunchuan Liu, Hongcheng Yang, Cunlin Zhang, Jingsuo He","doi":"10.1016/j.phycom.2025.102772","DOIUrl":"10.1016/j.phycom.2025.102772","url":null,"abstract":"<div><div>Reflective metasurfaces have emerged as a crucial component for 6G communications due to their capacity for effective signal control and modulation in the high-frequency range. A simple and accurate path loss model for metasurfaces is fundamental for optimizing metasurface-assisted wireless communication systems. This study proposes an anomalous reflective metasurface structure based on a Metal-Insulator-Metal (MIM) configuration. Using a real-time high-frequency measurement system, the path loss of this metasurface-assisted wireless communication system was measured across three dimensions: broad bandwidth (230 GHz to 330 GHz), wide incidence angle (0°to 40°), and reception distance (0.5 m to 1.9 m). Experimental results were compared with the predictions of the metasurface-assisted path loss model, confirming its accuracy and applicability at frequencies from 230 GHz to 330 GHz. Moreover, we outline the conditions for model applicability and the design parameter requirements for metasurface unit structures in the aforementioned frequency range. These measurement data facilitate the development of accurate channel models, offering valuable support for the design and optimization of communication systems, thereby enhancing their performance and reliability.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102772"},"PeriodicalIF":2.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Orthogonal Gradient Multi-Agent Deep Reinforcement Learning-based Algorithm for Spectrum Resource Optimization in UAV Swarm 基于正交梯度多智能体深度强化学习的无人机群频谱资源优化算法

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-14 DOI: 10.1016/j.phycom.2025.102770

Dengke Lou , Boyu Wan , Yu Zhang , Yihang Du , Fayu Wan , Yong Chen

{"title":"Orthogonal Gradient Multi-Agent Deep Reinforcement Learning-based Algorithm for Spectrum Resource Optimization in UAV Swarm","authors":"Dengke Lou , Boyu Wan , Yu Zhang , Yihang Du , Fayu Wan , Yong Chen","doi":"10.1016/j.phycom.2025.102770","DOIUrl":"10.1016/j.phycom.2025.102770","url":null,"abstract":"<div><div>In recent years, Unmanned Aerial Vehicle (UAV) swarm technology has made rapid progress, but communication problems remain a key factor limiting its widespread application. This study proposes an Orthogonal Gradient Multi-Agent Deep Reinforcement Learning-based Algorithm for Spectrum Resource Optimization in UAV swarm (OG-MADRL) to solve this problem. Specifically, to address the potential issue of gradient instability that may arise during the spectrum resource optimization process for UAV swarm, this study introduces an Orthogonal Gradient system (OG), which synergistically combines orthogonal initialization with global gradient clipping. This approach effectively alleviates both gradient explosion and vanishing phenomena, thereby enhancing training stability and accelerating convergence. To satisfy dynamic communication demands, a sophisticated reward mechanism is designed to enable flexible resource allocation to each UAV. To overcome the poor coordination in distributed training frameworks, the proposes algorithm is implemented within a Centralized Training and Distributed Execution (CTDE) framework, efficiently integrating global information to enable rapid responses to environmental changes. Simulation results show that, compared to existing algorithms, the OG-MADRL algorithm not only improves cluster throughput and enhances training stability but also exhibits superior adaptability and robustness in interference environment with dynamic communication demands.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102770"},"PeriodicalIF":2.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A reliability-controllable secure transmission strategy for cooperative cognitive vehicular networks under Gaussian channel error estimation 基于高斯信道误差估计的协同认知车辆网络可靠可控安全传输策略

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-12 DOI: 10.1016/j.phycom.2025.102766

Fan Wang , Lin Su , Haiyan Huang , Zufang Dou , Li Zhu , Shaoyi Du

{"title":"A reliability-controllable secure transmission strategy for cooperative cognitive vehicular networks under Gaussian channel error estimation","authors":"Fan Wang , Lin Su , Haiyan Huang , Zufang Dou , Li Zhu , Shaoyi Du","doi":"10.1016/j.phycom.2025.102766","DOIUrl":"10.1016/j.phycom.2025.102766","url":null,"abstract":"<div><div>Cognitive radio (CR) and cooperative communication (CC) represent two potent technologies designed to alleviate spectrum scarcity and improve the throughput of vehicular networks, while their integration has introduced multifaceted security concerns. This work explores the tradeoff between reliability and physical layer security (PLS) within the underlay cooperative cognitive vehicular networks (CCVNs). In CCVNs, a secondary vehicle communicates with the destination vehicle via a decode-and-forward (DF) relay, and an eavesdropper with imperfect channel state information (ipCSI) is present in the process. We adopt a more realistic system model considering Gaussian channel error estimation. Based on this model, we design a reliability-controllable secure transmission strategy and derive closed-form expressions for key performance indicators, including transmission delay, security, reliability, and throughput. These expressions are obtained by leveraging the computed cumulative distribution function (CDF) of the instantaneous equivalent signal-to-noise ratio (SNR). Furthermore, we optimize key parameters to maximize the secrecy throughput while meeting reliability constraints. Results from numerical calculations and simulation experiments highlight the significant improvement in reliability offered by the proposed strategy over conventional methods.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102766"},"PeriodicalIF":2.0,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A new peak width NLMS filtering scheme for a DVB-T based Passive Bistatic Radar 一种新的基于DVB-T的无源双基地雷达峰宽NLMS滤波方案

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-12 DOI: 10.1016/j.phycom.2025.102768

Alaeddine Aouane, Toufik Laroussi

{"title":"A new peak width NLMS filtering scheme for a DVB-T based Passive Bistatic Radar","authors":"Alaeddine Aouane, Toufik Laroussi","doi":"10.1016/j.phycom.2025.102768","DOIUrl":"10.1016/j.phycom.2025.102768","url":null,"abstract":"<div><div>Adaptive cancellation is the key stage in an PBR (Passive Bistatic Radar) signal processing. In order to achieve a detection with a low false alarm rate, the main role of the adaptive cancellation is the removal of the interferences from the target echoes, which can often originate from weak signals. It is well known that the conventional NLMS (Normalized Least Mean Square) and its frequency domain version, the FBLMS (Fast Bloc Least Mean Square) are inefficient when they come to the cancellation of both non-zero Doppler multipath components and strong target echoes. Although efficient in the cancellation of both cited problems inherent to the NLMS filter, its variants such as the MCNLMS (Multi Channel NLMS), the TD-SWNLMS (Two Dimensional-Sparse Weight NLMS) and the ECA (Extensive Cancellation Algorithm) yield significant computational complexity. To alleviate these difficulties, we propose to simulate a PBR based DVB-T (Digital Video Broadcasting-Terrestrial) signal model, based on a novel 1D-NLMS (One Dimensional-NLMS) filtering scheme called the PWNLMS (Peak Width NLMS). In doing this, the filter length of the proposed filter should adapt to the accumulation of the peaks width of the CAF (Cross Ambiguity Function) and a vector of step sizes whose length should be equal to the number of the peaks. In order to obtain an optimum convergence with a low complexity, the proposed filter should guarantee an effective and a smooth control of the direct signal, multiple paths and strong target echoes cancellation.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102768"},"PeriodicalIF":2.0,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stacked intelligent metasurfaces-aided full-duplex cooperative rate-splitting multiple access system 堆叠智能元表面辅助全双工协同分速多址系统

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-11 DOI: 10.1016/j.phycom.2025.102765

Chenghan Liang, Qiwei Huai, Yuanyi Liang, Weina Yuan

引用次数: 0

Active-RIS enabled secure NOMA networks: Joint transmit/reflect beamforming optimization 主动ris支持的安全NOMA网络：联合发射/反射波束形成优化

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-11 DOI: 10.1016/j.phycom.2025.102751

Lijuan Zhong , Mingsheng Wei , Shidang Li , Siyi Duan , Weiqiang Tan , Chunguo Li

{"title":"Active-RIS enabled secure NOMA networks: Joint transmit/reflect beamforming optimization","authors":"Lijuan Zhong , Mingsheng Wei , Shidang Li , Siyi Duan , Weiqiang Tan , Chunguo Li","doi":"10.1016/j.phycom.2025.102751","DOIUrl":"10.1016/j.phycom.2025.102751","url":null,"abstract":"<div><div>The integration of Non-Orthogonal Multiple Access (NOMA) and Reconfigurable Intelligent Surface (RIS) provides a powerful method to improve the coverage and capacity of wireless communication systems. However, protecting the communication security of RIS assisted networks is particularly important in situations where eavesdroppers are able to actively interfere with the communication. Passive RIS cannot effectively cope with the dual fading problem in signal transmission. To address this, we propose an active RIS assisted NOMA scheme. Active RIS can enhance communication security by adjusting the reflective characteristics of the signal. Additionally, we introduce artificial noise to reduce the information accessible to eavesdroppers. Specifically, by jointly optimizing the transmit beamforming at the base station, the artificial noise signal and the reflection coefficients of the active RIS, the security of the legitimate users and the maximization of the rate are achieved under the conditions of satisfying the user rate requirements, the power constraints of the base station and the active RIS, and the Successive Interference Cancellation (SIC). To solve this nonconvex optimization problem, this paper decomposes it into two subproblems and converts it into a convex problem using Successive Convex Approximation (SCA) and first-order Taylor’s method, and proposes an alternative optimization algorithm for iterative solution. Empirical data indicates that the scheme in question yields a minimum enhancement of 50% when active RIS and artificial noise are utilized, as opposed to a passive RIS scheme, thus offering a robust and safeguarded approach for the development of future wireless communication systems.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102751"},"PeriodicalIF":2.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144632392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating channel knowledge map and deep reinforcement learning for optimizing RIS-assisted MU-MISO systems 整合渠道知识图谱和深度强化学习优化ris辅助MU-MISO系统

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-11 DOI: 10.1016/j.phycom.2025.102769

Mingkang Yang , Xingquan Li , Chunlong He

{"title":"Integrating channel knowledge map and deep reinforcement learning for optimizing RIS-assisted MU-MISO systems","authors":"Mingkang Yang , Xingquan Li , Chunlong He","doi":"10.1016/j.phycom.2025.102769","DOIUrl":"10.1016/j.phycom.2025.102769","url":null,"abstract":"<div><div>A method that combines technical channel knowledge mapping (CKM) with deep reinforcement learning (DRL) to jointly optimize the phase offsets for transmission beamforming and reconfigurable intelligent surfaces (RIS) is developed in multi-user multiple-input single-output (MU-MISO) systems. The objective of the scheme is to enhance the overall downlink capacity under phase-sensitive reflection amplitude modeling conditions. The initial phase of the research involves pre-training using CKM to construct a model capable of accounting for positioning errors. Subsequently, the model will be migrated to a real scenario and formally trained based on the channel information that are obtained from channel estimation with channel estimation error. The proposed approach can efficiently exploit the environmental information and thus improve the performance and robustness of wireless communication systems. The results show that our approach has the potential to address the challenges of channel knowledge acquisition in hardware-constrained RIS-assisted wireless communication systems.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102769"},"PeriodicalIF":2.0,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sparse Bayesian estimation and signal recovery of fractional channels in OTFS systems OTFS系统中分数信道的稀疏贝叶斯估计与信号恢复

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-10 DOI: 10.1016/j.phycom.2025.102727

Zhanjun Jiang , Yuxin Liu , Zhengyuan Wu , Junhui Zhao

{"title":"Sparse Bayesian estimation and signal recovery of fractional channels in OTFS systems","authors":"Zhanjun Jiang , Yuxin Liu , Zhengyuan Wu , Junhui Zhao","doi":"10.1016/j.phycom.2025.102727","DOIUrl":"10.1016/j.phycom.2025.102727","url":null,"abstract":"<div><div>In high-speed mobile scenarios, fractional delay and fractional Doppler effects are pervasive, disrupting the inherent sparse structure of the Orthogonal Time Frequency Space (OTFS) system in the delay-Doppler (DD) domain. This leads to the spreading of channel response energy, which not only significantly increases the complexity of channel estimation(CE) algorithms, but also reduces the accuracy of CE. In response to this issue, a two-stage CE scheme is proposed based on Sparse Adaptive Matching Pursuit (SAMP) and Off-Grid Sparse Bayesian Learning (OGSBL) algorithms in this paper. In the signal recovery stage, a doubly fractional CE model is established. On this basis, sparse signals are recovered by using the Sparsity Adaptive Matching Pursuit (SAMP) algorithm to achieve rapid channel path location and preliminary estimation, thus making more effective use of the sparsity of the DD domain channel. In the Bayesian optimization stage, the recovered signal is used as the initial input, the CE is further optimized by SBL. Meanwhile, to effectively mitigate the system’s Peak-to-Average Power Ratio (PAPR), Zadoff–Chu (ZC) sequences are incorporated into the pilot structure design. Numerical simulations were conducted to compare the PAPR and Normalized Mean Square Error (NMSE) performance across various pilot patterns, confirming the efficacy of the proposed approach. Simulation results demonstrate that the suggested approach enhances CE precision and speeds up the algorithm’s convergence.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102727"},"PeriodicalIF":2.0,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144633288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Robust and adaptive semantic noise for complex secure communication networks 复杂安全通信网络的鲁棒自适应语义噪声

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-07 DOI: 10.1016/j.phycom.2025.102763

Yao Cai

{"title":"Robust and adaptive semantic noise for complex secure communication networks","authors":"Yao Cai","doi":"10.1016/j.phycom.2025.102763","DOIUrl":"10.1016/j.phycom.2025.102763","url":null,"abstract":"<div><div>Privacy protection and robust transmission play critical roles in secure semantic communication, especially in open wireless environments with the presence of eavesdropping and for sensitive information such as self-management health information of patients with chronic diseases. Traditional physical layer technologies lack adaptability and efficiency in semantic-level threats due to sole attention to symbol protection. To address these challenges, this paper introduces a novel semantic security approach that integrates semantic noise into the transmitted semantic information to enhance the semantic security and improve the transmission robustness, even with the public semantic coding method and codebook. Specifically, we propose a vector quantized variational semantic security autoencoder (VQ-VSSAE), which can generate the semantic symbols by extracting essential features from original data and encoding them into a structured security codebook. By leveraging the semantic context and real-time channel state information (CSI), VQ-VSSAE dynamically produces the semantic noise to confuse the eavesdropper and mitigate the background interference through the noise-enabled VQ security design with semantic ambiguity, thus avoiding potential semantic leakage. Extensive simulations are conducted to evaluate the performance of the proposed system. The results demonstrate that VQ-VSSAE outperforms existing benchmark schemes in terms of semantic security and transmission robustness.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102763"},"PeriodicalIF":2.0,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144632393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cognitive semantic communications with codebook-based adaptive correction for image classification 基于码本自适应校正的认知语义通信图像分类

IF 2 4区计算机科学

Physical Communication Pub Date : 2025-07-05 DOI: 10.1016/j.phycom.2025.102764

Yabin Weng , Jinghao Sun , Junjie Wu

{"title":"Cognitive semantic communications with codebook-based adaptive correction for image classification","authors":"Yabin Weng , Jinghao Sun , Junjie Wu","doi":"10.1016/j.phycom.2025.102764","DOIUrl":"10.1016/j.phycom.2025.102764","url":null,"abstract":"<div><div>Conventional bit-oriented communication paradigms face several critical challenges in emerging sixth-generation (6G) wireless scenarios. One of the key challenges is low-efficient symbol transmission without considering task-oriented semantic importance, thus leading to high bandwidth consumption. To overcome this challenge, we propose a novel cognitive semantic communication (CSC) framework for the image classification, where the remote facial expression recognition for drivers is considered. Unlike conventional semantic communication methods that passively handle predefined semantic features, the proposed CSC framework actively identifies and adapts the most critical emotional features for transmission, substantially reducing bandwidth and signal quality requirements while preserving essential expression details. Moreover, for the first time, we design a cognitive-inspired semantic inference model equipped with a codebook-based correction mechanism to mitigate semantic distortion caused by physical channel impairments, enhancing reliability and interpretability under adverse conditions. Extensive simulation results demonstrate that proposed CSC can significantly outperform existing methods in recognition accuracy under constrained communication scenarios. By integrating cognitive-inspired semantic extraction, intelligent encoding–decoding processes, and context-aware inference, our proposed approach advances the state of the art in semantic communications for the image classification, offering a more robust and resource-efficient solution.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"72 ","pages":"Article 102764"},"PeriodicalIF":2.0,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144595674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0