Pub Date : 2024-10-17DOI: 10.1016/j.phycom.2024.102522
Hui Chen , Yuhui Zhou , Shufen Chen , Xilai Wang , Peiqing Guo , Gaojian Huang , Xingwang Li
Different from linear arrays that can resolve only one angular component, two-dimensional (2-D) array patterns enable to remove the cone of uncertainty and right/left ambiguities generated in a linear array. Motivated by this, a novel structure of 2-D time-modulated planar arrays (TMPAs) is developed to synthesize directional modulation (DM) symbols in this paper. The proposed 2-D TMPA DM transmitter can synthesize multicarrier DM symbols with suppressing the mirror harmonic frequencies and provide a higher power efficiency. This is demonstrated by way of simulations of a multi-beam 8*8 element planar antenna array and its security performance is shown via the bit error rate (BER) metric.
{"title":"Time-modulated planar arrays enabled directional modulation symbol synthesis","authors":"Hui Chen , Yuhui Zhou , Shufen Chen , Xilai Wang , Peiqing Guo , Gaojian Huang , Xingwang Li","doi":"10.1016/j.phycom.2024.102522","DOIUrl":"10.1016/j.phycom.2024.102522","url":null,"abstract":"<div><div>Different from linear arrays that can resolve only one angular component, two-dimensional (2-D) array patterns enable to remove the cone of uncertainty and right/left ambiguities generated in a linear array. Motivated by this, a novel structure of 2-D time-modulated planar arrays (TMPAs) is developed to synthesize directional modulation (DM) symbols in this paper. The proposed 2-D TMPA DM transmitter can synthesize multicarrier DM symbols with suppressing the mirror harmonic frequencies and provide a higher power efficiency. This is demonstrated by way of simulations of a multi-beam 8*8 element planar antenna array and its security performance is shown via the bit error rate (BER) metric.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102522"},"PeriodicalIF":2.0,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529649","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}
Pub Date : 2024-10-17DOI: 10.1016/j.phycom.2024.102523
Sen Wang , Baowang Lian , Musen Liu , Junyao Zhang , Varun G. Menon , Xingwang Li
In this work, we delve into the covertness performance of the reconfigurable intelligent surface (RIS) symbiotic ambient backscatter communication (AmBC) systems, where the RIS is partitioned into two zones to serve covert and public users. To impede with the monitor’s detection, the source deliberately transmits both information and interference signals. Specifically, we derive closed-form expressions for the detection error probability (DEP) and outage probabilities. Subsequently, the effective covert rate (ECR) is maximized by optimizing the power allocation factor and the number of each zone reflective elements. Finally, we investigate the energy efficiency (EE) of the considered system. Simulation results validate the accuracy of the analysis, underscoring that the RIS-segmented symbiotic AmBC systems can achieve better covertness by improving the interference cancellation capability and dividing the optimal RIS zones.
{"title":"Covert performance analysis of integrated RIS and backscatter NOMA communication networks","authors":"Sen Wang , Baowang Lian , Musen Liu , Junyao Zhang , Varun G. Menon , Xingwang Li","doi":"10.1016/j.phycom.2024.102523","DOIUrl":"10.1016/j.phycom.2024.102523","url":null,"abstract":"<div><div>In this work, we delve into the covertness performance of the reconfigurable intelligent surface (RIS) symbiotic ambient backscatter communication (AmBC) systems, where the RIS is partitioned into two zones to serve covert and public users. To impede with the monitor’s detection, the source deliberately transmits both information and interference signals. Specifically, we derive closed-form expressions for the detection error probability (DEP) and outage probabilities. Subsequently, the effective covert rate (ECR) is maximized by optimizing the power allocation factor and the number of each zone reflective elements. Finally, we investigate the energy efficiency (EE) of the considered system. Simulation results validate the accuracy of the analysis, underscoring that the RIS-segmented symbiotic AmBC systems can achieve better covertness by improving the interference cancellation capability and dividing the optimal RIS zones.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102523"},"PeriodicalIF":2.0,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142528680","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}
Pub Date : 2024-10-15DOI: 10.1016/j.phycom.2024.102521
Huanting Liu , Wenwei Luo , Jize Song , Lihong Feng , Jiliang Zhang , Gaofeng Pan
Due to the non-ideal characteristics of the transceivers, there always exists some residual hardware impairments (RHIs) in practical communication systems, which could lead to degraded system performance. Therefore, in this study, we investigate wireless-powered relaying assisted underwater wireless optical communication-radio frequency systems in the context of RHIs. Specifically, considering the scenario that a multi-aperture and multi-antenna relay employs both a selection combining and a transmit antenna selection schemes to process the received and transmitted signals, we first obtain both the probability density function and cumulative distribution function of the instantaneous signal-to-interference-plus-noise ratio of the first link with RHIs. Next, utilizing those expressions as well as the Meijer’s- and Fox’s- functions, the analytical and asymptotic expressions of outage probability as well as analytical average bit error rate expressions are obtained. In addition, Monte-Carlo simulations are performed to check the accuracy of those obtained expressions.
{"title":"Wireless-powered relaying SIMO-UWOC/MISO-RF networks with residual hardware impairments","authors":"Huanting Liu , Wenwei Luo , Jize Song , Lihong Feng , Jiliang Zhang , Gaofeng Pan","doi":"10.1016/j.phycom.2024.102521","DOIUrl":"10.1016/j.phycom.2024.102521","url":null,"abstract":"<div><div>Due to the non-ideal characteristics of the transceivers, there always exists some residual hardware impairments (RHIs) in practical communication systems, which could lead to degraded system performance. Therefore, in this study, we investigate wireless-powered relaying assisted underwater wireless optical communication-radio frequency systems in the context of RHIs. Specifically, considering the scenario that a multi-aperture and multi-antenna relay employs both a selection combining and a transmit antenna selection schemes to process the received and transmitted signals, we first obtain both the probability density function and cumulative distribution function of the instantaneous signal-to-interference-plus-noise ratio of the first link with RHIs. Next, utilizing those expressions as well as the Meijer’s-<span><math><mi>G</mi></math></span> and Fox’s-<span><math><mi>H</mi></math></span> functions, the analytical and asymptotic expressions of outage probability as well as analytical average bit error rate expressions are obtained. In addition, Monte-Carlo simulations are performed to check the accuracy of those obtained expressions.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102521"},"PeriodicalIF":2.0,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529647","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}
Free space optics (FSO) offers a promising opportunity to enhance next-generation network’s capacity with its unlicensed spectrum and wide bandwidth. However, jamming attacks, coupled with inherent anomalies in the FSO-based channel, threaten the performance of these networks. This is especially problematic for security-sensitive applications that demand a resilient communication infrastructure. To address this issue, optical intelligent reflecting surfaces (IRS) and unmanned aerial vehicles (UAVs) can provide promising solutions. This work introduces an efficient approach for mirror element assignment in UAV-assisted FSO-based networks, aimed at mitigating reactive jamming attacks while satisfying users’ quality-of-service (QoS) requirements. To ensure network reliability, we formulate an optimization problem that enhances overall network performance by simultaneously allocating resources such as mirror elements with awareness of jamming attacks. The formulated optimization problem is a binary linear programming problem, which is generally NP-hard. To address this, we introduce a batch-based sequential fixing linear programming procedure called the Reactive Jamming-Aware Mirror Element Allocation (RJA-MEA) scheme. This scheme optimally assigns mirror elements to satisfy the users’ rate demands. In this paper, the performance of the RJA-MEA scheme is compared with reference schemes such as Reactive Jamming Unaware-Mirror Element Allocation (RJU-MEA), Reactive Jamming-Aware Equal Mirror Element Allocation (RJA-EMEA), and Reactive Jamming Unaware-Equal Mirror Element Allocation (RJU-EMEA) schemes. The simulation results reveal that the proposed RJA-MEA scheme surpasses existing reference schemes, thereby significantly improving the overall network sumrate performance.
{"title":"On mitigating reactive jamming with dynamic resource allocation in optical IRS and UAV-assisted FSO-based networks","authors":"Priyanka Singh , Haythem Bany Salameh , Vivek Ashok Bohara , Anand Srivastava , Moussa Ayyash","doi":"10.1016/j.phycom.2024.102520","DOIUrl":"10.1016/j.phycom.2024.102520","url":null,"abstract":"<div><div>Free space optics (FSO) offers a promising opportunity to enhance next-generation network’s capacity with its unlicensed spectrum and wide bandwidth. However, jamming attacks, coupled with inherent anomalies in the FSO-based channel, threaten the performance of these networks. This is especially problematic for security-sensitive applications that demand a resilient communication infrastructure. To address this issue, optical intelligent reflecting surfaces (IRS) and unmanned aerial vehicles (UAVs) can provide promising solutions. This work introduces an efficient approach for mirror element assignment in UAV-assisted FSO-based networks, aimed at mitigating reactive jamming attacks while satisfying users’ quality-of-service (QoS) requirements. To ensure network reliability, we formulate an optimization problem that enhances overall network performance by simultaneously allocating resources such as mirror elements with awareness of jamming attacks. The formulated optimization problem is a binary linear programming problem, which is generally NP-hard. To address this, we introduce a batch-based sequential fixing linear programming procedure called the Reactive Jamming-Aware Mirror Element Allocation (RJA-MEA) scheme. This scheme optimally assigns mirror elements to satisfy the users’ rate demands. In this paper, the performance of the RJA-MEA scheme is compared with reference schemes such as Reactive Jamming Unaware-Mirror Element Allocation (RJU-MEA), Reactive Jamming-Aware Equal Mirror Element Allocation (RJA-EMEA), and Reactive Jamming Unaware-Equal Mirror Element Allocation (RJU-EMEA) schemes. The simulation results reveal that the proposed RJA-MEA scheme surpasses existing reference schemes, thereby significantly improving the overall network sumrate performance.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102520"},"PeriodicalIF":2.0,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142445176","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}
Pub Date : 2024-10-09DOI: 10.1016/j.phycom.2024.102516
Huaqiang Chen , Weiqiang Tan , Jiajia Guo , Feiran Yang
Multi-user massive multiple-input multiple-output (MIMO) communication systems consume too much downlink bandwidth due to the huge channel state information (CSI) feedback, deep learning-based CSI feedback approaches fortunately can alleviate the feedback overhead while obtaining an accurate CSI. However, there is a trade-off between the high feedback performance and low computational complexity. In this paper, a low-complexity CSI feedback approach is proposed based on spatial and channel attention mechanism, namely the Spatial and Channel Attention Network (SCANet). Specifically, the spatial and channel attention mechanism makes the network’s attention mainly focus on the specific spatial regions and key feature channels. We devise a serial architecture in the encoder that composes of Spatial and Channel Attention Block (SCAB) and Encoder Transformer Block. Moreover, we design a hybrid architecture in the decoder that composes of the CNNs Block and Decoder Transformer Block. These designs enable the network to effectively extract both global and local CSI features. Computer simulations in both the indoor and outdoor scenarios show that under the same system configurations, the proposed low-complexity SCANet achieves almost the same performance as the state-of-the-art network while reducing the computational complexity by 85.76% fewer floating-point operations per second (FLOPS) on average.
{"title":"SCANet: A lightweight deep learning network for massive MIMO CSI feedback based on spatial and channel attention mechanism","authors":"Huaqiang Chen , Weiqiang Tan , Jiajia Guo , Feiran Yang","doi":"10.1016/j.phycom.2024.102516","DOIUrl":"10.1016/j.phycom.2024.102516","url":null,"abstract":"<div><div>Multi-user massive multiple-input multiple-output (MIMO) communication systems consume too much downlink bandwidth due to the huge channel state information (CSI) feedback, deep learning-based CSI feedback approaches fortunately can alleviate the feedback overhead while obtaining an accurate CSI. However, there is a trade-off between the high feedback performance and low computational complexity. In this paper, a low-complexity CSI feedback approach is proposed based on spatial and channel attention mechanism, namely the Spatial and Channel Attention Network (SCANet). Specifically, the spatial and channel attention mechanism makes the network’s attention mainly focus on the specific spatial regions and key feature channels. We devise a serial architecture in the encoder that composes of Spatial and Channel Attention Block (SCAB) and Encoder Transformer Block. Moreover, we design a hybrid architecture in the decoder that composes of the CNNs Block and Decoder Transformer Block. These designs enable the network to effectively extract both global and local CSI features. Computer simulations in both the indoor and outdoor scenarios show that under the same system configurations, the proposed low-complexity SCANet achieves almost the same performance as the state-of-the-art network while reducing the computational complexity by 85.76% fewer floating-point operations per second (FLOPS) on average.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102516"},"PeriodicalIF":2.0,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142434323","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}
Pub Date : 2024-10-09DOI: 10.1016/j.phycom.2024.102510
Chuangming Zheng , Jiayang Ban , Liqin Shi , Yinghui Ye
In this paper, we investigate a cognitive radio (CR) inspired rate splitting multiple access (RSMA) aided mobile edge computing (MEC) network, where hardware impairments (HIs) in all transceivers are considered. Given that allowing the secondary user (SU) to share the resource with the primary user (PU) for data offloading does not degrade the PU’s offloading performance, we derive closed-form expressions for the rate-splitting parameter and power allocation coefficient at the SU to maximize its offloading rate. Using the derived parameters, we then derive the successful computation probability (SCP), which is defined as the probability that both the PU and SU can successfully compute their task bits within a given latency budget, into the closed form. To further enhance the performance of the CR inspired RSMA-MEC network with HIs, a SCP maximization-based problem is formulated to jointly optimize the task offloading ratio and task offloading time of both the SU and PU. Leveraging the convex theory, we obtain the optimal solutions in the closed form. Simulation results confirm the following two insights. First, the presence of HIs leads to a decreasing on the SCP and the SCP approaches to a constant which is less than 1 with the increase of the transmit power. Second, with the optimal task offloading ratio and time, the CR inspired RSMA-MEC achieves the highest SCP compared to the existing schemes.
本文研究了一种受认知无线电(CR)启发的速率分裂多重接入(RSMA)辅助移动边缘计算(MEC)网络,其中考虑了所有收发器的硬件损伤(HI)。考虑到允许次要用户(SU)与主要用户(PU)共享资源进行数据卸载不会降低 PU 的卸载性能,我们推导出了速率分割参数和 SU 功率分配系数的闭式表达式,以最大化其卸载速率。利用推导出的参数,我们得出了成功计算概率 (SCP),即 PU 和 SU 在给定延迟预算内成功计算其任务比特的概率。为了进一步提高具有 HI 的 CR 启发 RSMA-MEC 网络的性能,我们提出了一个基于 SCP 最大化的问题,以共同优化 SU 和 PU 的任务卸载率和任务卸载时间。利用凸理论,我们得到了闭合形式的最优解。仿真结果证实了以下两个观点。首先,HI 的存在导致 SCP 下降,并且随着发射功率的增加,SCP 接近于小于 1 的常数。其次,与现有方案相比,在最佳任务卸载率和时间下,受 CR 启发的 RSMA-MEC 实现了最高的 SCP。
{"title":"Cognitive radio inspired RSMA-MEC under hardware impairments: Performance analysis and optimization","authors":"Chuangming Zheng , Jiayang Ban , Liqin Shi , Yinghui Ye","doi":"10.1016/j.phycom.2024.102510","DOIUrl":"10.1016/j.phycom.2024.102510","url":null,"abstract":"<div><div>In this paper, we investigate a cognitive radio (CR) inspired rate splitting multiple access (RSMA) aided mobile edge computing (MEC) network, where hardware impairments (HIs) in all transceivers are considered. Given that allowing the secondary user (SU) to share the resource with the primary user (PU) for data offloading does not degrade the PU’s offloading performance, we derive closed-form expressions for the rate-splitting parameter and power allocation coefficient at the SU to maximize its offloading rate. Using the derived parameters, we then derive the successful computation probability (SCP), which is defined as the probability that both the PU and SU can successfully compute their task bits within a given latency budget, into the closed form. To further enhance the performance of the CR inspired RSMA-MEC network with HIs, a SCP maximization-based problem is formulated to jointly optimize the task offloading ratio and task offloading time of both the SU and PU. Leveraging the convex theory, we obtain the optimal solutions in the closed form. Simulation results confirm the following two insights. First, the presence of HIs leads to a decreasing on the SCP and the SCP approaches to a constant which is less than 1 with the increase of the transmit power. Second, with the optimal task offloading ratio and time, the CR inspired RSMA-MEC achieves the highest SCP compared to the existing schemes.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102510"},"PeriodicalIF":2.0,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427942","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}
Pub Date : 2024-10-05DOI: 10.1016/j.phycom.2024.102502
Enyu Li, Meijuan Zheng, Zanyang Liang, Ye Wang, Haoming Wang
Aiming at the scenario where the eavesdropper try to eavesdrop on the confidential messages of secondary trusted users, two physical-layer network coding (PNC) strategies, namely dual power superposition (PS-PS) encoding strategy and bit-level exclusive-or power superposition (XOR-PS) encoding strategy, are proposed to improve the security performance of cognitive non-orthogonal multiple access (NOMA) networks with the help of the data transmitted by the primary user. Considering the overlay spectrum sharing mechanism and the imperfect successive interference cancellation (SIC) technology, we first derive the closed-form accurate expressions of the outage probability and intercept probability of the secondary network with these two schemes over Rayleigh fading, and also give the asymptotic outage probability in the high signal-to-noise ratio (SNR) regime. Then, the correctness of the theoretical results is verified by simulation. For comparison, we also use the scheme without the assistance of the primary user as the benchmark scheme, which is represented by NPS. Finally, the simulation results show that the security of the proposed PS-PS and XOR-PS schemes is much better than that of the NPS scheme in the case of without reducing the outage performance.
{"title":"Improving the security of NOMA cognitive networks","authors":"Enyu Li, Meijuan Zheng, Zanyang Liang, Ye Wang, Haoming Wang","doi":"10.1016/j.phycom.2024.102502","DOIUrl":"10.1016/j.phycom.2024.102502","url":null,"abstract":"<div><div>Aiming at the scenario where the eavesdropper try to eavesdrop on the confidential messages of secondary trusted users, two physical-layer network coding (PNC) strategies, namely dual power superposition (PS-PS) encoding strategy and bit-level exclusive-or power superposition (XOR-PS) encoding strategy, are proposed to improve the security performance of cognitive non-orthogonal multiple access (NOMA) networks with the help of the data transmitted by the primary user. Considering the overlay spectrum sharing mechanism and the imperfect successive interference cancellation (SIC) technology, we first derive the closed-form accurate expressions of the outage probability and intercept probability of the secondary network with these two schemes over Rayleigh fading, and also give the asymptotic outage probability in the high signal-to-noise ratio (SNR) regime. Then, the correctness of the theoretical results is verified by simulation. For comparison, we also use the scheme without the assistance of the primary user as the benchmark scheme, which is represented by NPS. Finally, the simulation results show that the security of the proposed PS-PS and XOR-PS schemes is much better than that of the NPS scheme in the case of without reducing the outage performance.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102502"},"PeriodicalIF":2.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438244","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}
Pub Date : 2024-10-05DOI: 10.1016/j.phycom.2024.102515
Xinwei Yue , Yang Zhou , Ce Zhang , Jingjing Zhao , Yanan Ma , Yuanyuan Yao , Chongwen Huang
Simultaneously transmitting and reflecting surface (STARS) has emerged as a revolutionary technology to enable full spatial coverage. This paper investigates the application of STARS into non-orthogonal multiple access based ambient backscatter communication (NOMA-AmBC) networks, where the backscatter signals are separately reflected and transmitted to user n and user f with the help of STARS. Specifically, we derive new exact and approximate expressions of outage probability and ergodic rate for backscatter signals and a pair of users. Based on the asymptotic analytical results, the diversity order and multiplexing gain are provided for STARS-NOMA-AmBC networks. For the purpose of comparison, we further deduce the exact expressions of outage probability and ergodic rate for STARS aided orthogonal multiple access AmBC (STARS-OMA-AmBC) networks. The numerical results confirm our analysis and show that: (i) The outage behaviors of STARS-NOMA-AmBC are superior to that of STARS-OMA-AmBC; (ii) As the number of reconfigurable elements and backscatter coefficients increases, the backscatter signal has ability to acquire the greater performance gains; and (iii) The ergodic performance of STARS-NOMA-AmBC networks is better than that of reconfigurable intelligent surface assisted AmBC networks.
{"title":"STARS aided NOMA ambient backscatter communications","authors":"Xinwei Yue , Yang Zhou , Ce Zhang , Jingjing Zhao , Yanan Ma , Yuanyuan Yao , Chongwen Huang","doi":"10.1016/j.phycom.2024.102515","DOIUrl":"10.1016/j.phycom.2024.102515","url":null,"abstract":"<div><div>Simultaneously transmitting and reflecting surface (STARS) has emerged as a revolutionary technology to enable full spatial coverage. This paper investigates the application of STARS into non-orthogonal multiple access based ambient backscatter communication (NOMA-AmBC) networks, where the backscatter signals are separately reflected and transmitted to user <em>n</em> and user <em>f</em> with the help of STARS. Specifically, we derive new exact and approximate expressions of outage probability and ergodic rate for backscatter signals and a pair of users. Based on the asymptotic analytical results, the diversity order and multiplexing gain are provided for STARS-NOMA-AmBC networks. For the purpose of comparison, we further deduce the exact expressions of outage probability and ergodic rate for STARS aided orthogonal multiple access AmBC (STARS-OMA-AmBC) networks. The numerical results confirm our analysis and show that: (i) The outage behaviors of STARS-NOMA-AmBC are superior to that of STARS-OMA-AmBC; (ii) As the number of reconfigurable elements and backscatter coefficients increases, the backscatter signal has ability to acquire the greater performance gains; and (iii) The ergodic performance of STARS-NOMA-AmBC networks is better than that of reconfigurable intelligent surface assisted AmBC networks.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102515"},"PeriodicalIF":2.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427434","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}
Pub Date : 2024-10-03DOI: 10.1016/j.phycom.2024.102513
Cheru Haile Tesfay , Zheng Xiang , Long Yang , Michael Abebe Berwo , Jabar Mahmood , Shehzad Ashraf Chaudhry
Therefore, this study aims to introduce a novel framework for leader and coordinator selection in a swarm of UAVs that may further reduce communication delay and increase the data transmission rate. The proposed reliable framework avoids single-point failure. We use an integrated greedy approach for leader selection using better channel gain, enhanced data transmission rate, and minimal round-trip delays as metrics. Furthermore, the UAV coordinator is selected based on the nearest distance. In addition, this study also proposes an efficient and iterative algorithm for the effective selection of UAV leaders and coordinators. The experimental results indicate that our proposed protocol minimizes delay by 20% and increases the data transmission rate by as compared with existing methods.
{"title":"An effective and efficient UAV leader selection scheme in swarm of UAVs","authors":"Cheru Haile Tesfay , Zheng Xiang , Long Yang , Michael Abebe Berwo , Jabar Mahmood , Shehzad Ashraf Chaudhry","doi":"10.1016/j.phycom.2024.102513","DOIUrl":"10.1016/j.phycom.2024.102513","url":null,"abstract":"<div><div>Therefore, this study aims to introduce a novel framework for leader and coordinator selection in a swarm of UAVs that may further reduce communication delay and increase the data transmission rate. The proposed reliable framework avoids single-point failure. We use an integrated greedy approach for leader selection using better channel gain, enhanced data transmission rate, and minimal round-trip delays as metrics. Furthermore, the UAV coordinator is selected based on the nearest distance. In addition, this study also proposes an efficient and iterative algorithm for the effective selection of UAV leaders and coordinators. The experimental results indicate that our proposed protocol minimizes delay by 20% and increases the data transmission rate by <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>2</mn></mrow></msup><mspace></mspace><mi>bps</mi></mrow></math></span> as compared with existing methods.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102513"},"PeriodicalIF":2.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427941","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}
Pub Date : 2024-10-01DOI: 10.1016/j.phycom.2024.102514
Yijie Bian , Jie Yang , Lingyun Dai , Xi Lin , Xinyao Cheng , Hang Que , Le Liang , Shi Jin
Millimeter wave (mmWave) communication has attracted extensive attention and research due to its wide bandwidth and abundant spectrum resources. Effective and fast beam tracking is a critical challenge for the practical deployment of mmWave communications. Existing studies demonstrate the potential of sensing-aided beam tracking. However, most studies are focus on single-modal data assistance without considering multi-modal calibration or the impact of inference latency of different sub-modules. Thus, in this study, we design a decision-level multi-modal (mmWave received signal power vector, RGB image and GPS data) fusion for sensing-aided beam tracking (DMBT) method. The proposed DMBT method includes three designed mechanisms, namely normal prediction process, beam misalignment alert and beam tracking correction. The normal prediction process conducts partial beam training instead of exhaustive beam training, which largely reduces large beam training overhead. It also comprehensively selects prediction results from multi-modal data to enhance the DMBT method robustness to noise. The beam misalignment alert based on RGB image and GPS data detects whether there exists beam misalignment and also predict the optimal beam. The beam tracking correction is designed to capture the optimal beam if misalignment happens by reusing certain blocks in normal prediction process and possibly outdated prediction results. Finally, we evaluate the proposed DMBT method in the vehicle-to-infrastructure scenario based on a real-world dataset. The results show that the method is capable of self-correction and mitigating the negative effect of the relative inference latency. Moreover, 75%–93% beam training overhead can be saved to maintain reliable communication even when faced with considerable noise in measurement data.
{"title":"Multi-modal fusion for sensing-aided beam tracking in mmWave communications","authors":"Yijie Bian , Jie Yang , Lingyun Dai , Xi Lin , Xinyao Cheng , Hang Que , Le Liang , Shi Jin","doi":"10.1016/j.phycom.2024.102514","DOIUrl":"10.1016/j.phycom.2024.102514","url":null,"abstract":"<div><div>Millimeter wave (mmWave) communication has attracted extensive attention and research due to its wide bandwidth and abundant spectrum resources. Effective and fast beam tracking is a critical challenge for the practical deployment of mmWave communications. Existing studies demonstrate the potential of sensing-aided beam tracking. However, most studies are focus on single-modal data assistance without considering multi-modal calibration or the impact of inference latency of different sub-modules. Thus, in this study, we design a decision-level multi-modal (mmWave received signal power vector, RGB image and GPS data) fusion for sensing-aided beam tracking (DMBT) method. The proposed DMBT method includes three designed mechanisms, namely normal prediction process, beam misalignment alert and beam tracking correction. The normal prediction process conducts partial beam training instead of exhaustive beam training, which largely reduces large beam training overhead. It also comprehensively selects prediction results from multi-modal data to enhance the DMBT method robustness to noise. The beam misalignment alert based on RGB image and GPS data detects whether there exists beam misalignment and also predict the optimal beam. The beam tracking correction is designed to capture the optimal beam if misalignment happens by reusing certain blocks in normal prediction process and possibly outdated prediction results. Finally, we evaluate the proposed DMBT method in the vehicle-to-infrastructure scenario based on a real-world dataset. The results show that the method is capable of self-correction and mitigating the negative effect of the relative inference latency. Moreover, 75%–93% beam training overhead can be saved to maintain reliable communication even when faced with considerable noise in measurement data.</div></div>","PeriodicalId":48707,"journal":{"name":"Physical Communication","volume":"67 ","pages":"Article 102514"},"PeriodicalIF":2.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427433","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}