SummaryIn this paper, the enhancement of global navigation satellite system (GNSS) adaptive acquisition using metaheuristic optimization techniques is proposed. The principal goal of this work is to optimize the cell averaging constant false alarm rate (CA‐CFAR) thresholding in Rayleigh fading channels. In GNSS acquisition, pilot and data blocks may have different thresholds. Thus, the optimization will focus on two scaling factors ( and ). Two fusion rules have been used here (“AND” and “OR”). Due to their performances in different optimization problems, metaheuristics have been chosen to be our tool for solving this kind of problem. Simulation results show that the optimized thresholds have an important influence on the performance of the acquisition system.
{"title":"Thresholding optimization of global navigation satellite system acquisition with constant false alarm rate detection using metaheuristic techniques","authors":"Mohamed Fouad Hassani, Abida Toumi, Sabra Benkrinah, Salim Sbaa","doi":"10.1002/dac.5938","DOIUrl":"https://doi.org/10.1002/dac.5938","url":null,"abstract":"SummaryIn this paper, the enhancement of global navigation satellite system (GNSS) adaptive acquisition using metaheuristic optimization techniques is proposed. The principal goal of this work is to optimize the cell averaging constant false alarm rate (CA‐CFAR) thresholding in Rayleigh fading channels. In GNSS acquisition, pilot and data blocks may have different thresholds. Thus, the optimization will focus on two scaling factors ( and ). Two fusion rules have been used here (“AND” and “OR”). Due to their performances in different optimization problems, metaheuristics have been chosen to be our tool for solving this kind of problem. Simulation results show that the optimized thresholds have an important influence on the performance of the acquisition system.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866810","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}
SummaryRelay selection plays a crucial role in enhancing the performance of wireless networks particularly in the context of cognitive radio (CR) systems with energy harvesters. In this paper, we propose a novel approach, namely, CGAPSO Shapley, for the best relay selection while simultaneously optimizing the parameters of signal‐to‐interference‐plus‐noise ratio (SINR), throughput, and outage probability. The CGAPSO Shapley algorithm combines the Shapley value, a cooperative game theory concept, with cellular genetic algorithm particle swarm optimization (CGAPSO) to achieve effective and efficient optimization of relay selection. The CGAPSO framework provides a hybrid structure that integrates cellular genetic algorithm (CGA) and particle swarm optimization (PSO), enabling simultaneous evolution of the population and particles within cells. The incorporation of the Shapley value and the hybrid CGAPSO framework enables effective exploration of the solution space and provides decision‐makers with comprehensive insights for relay selection. By utilizing the Shapley value, we assign weights to the relay nodes based on their contributions to the overall optimization objectives, considering their CR capabilities and energy harvesting capabilities. Some benchmark test functions are used to compare the hybrid algorithm with both the standard CGAPSO, Particle swarm optimization gravitational search algorithm (PSOGSA) and PSO algorithms in evolving best solution. The results show the hybrid algorithm possesses a better capability to escape from local optimums with faster convergence than the standard algorithms. The novel CGAPSO Shapley approach achieves an outage probability of 0.323324, marking a significant improvement of 60% over the outage probability achieved with conventional approach.
{"title":"Hybrid game theoretic strategy for optimal relay selection in energy harvesting cognitive radio network","authors":"Shalley Bakshi, Surbhi Sharma, Rajesh Khanna","doi":"10.1002/dac.5935","DOIUrl":"https://doi.org/10.1002/dac.5935","url":null,"abstract":"SummaryRelay selection plays a crucial role in enhancing the performance of wireless networks particularly in the context of cognitive radio (CR) systems with energy harvesters. In this paper, we propose a novel approach, namely, CGAPSO Shapley, for the best relay selection while simultaneously optimizing the parameters of signal‐to‐interference‐plus‐noise ratio (SINR), throughput, and outage probability. The CGAPSO Shapley algorithm combines the Shapley value, a cooperative game theory concept, with cellular genetic algorithm particle swarm optimization (CGAPSO) to achieve effective and efficient optimization of relay selection. The CGAPSO framework provides a hybrid structure that integrates cellular genetic algorithm (CGA) and particle swarm optimization (PSO), enabling simultaneous evolution of the population and particles within cells. The incorporation of the Shapley value and the hybrid CGAPSO framework enables effective exploration of the solution space and provides decision‐makers with comprehensive insights for relay selection. By utilizing the Shapley value, we assign weights to the relay nodes based on their contributions to the overall optimization objectives, considering their CR capabilities and energy harvesting capabilities. Some benchmark test functions are used to compare the hybrid algorithm with both the standard CGAPSO, Particle swarm optimization gravitational search algorithm (PSOGSA) and PSO algorithms in evolving best solution. The results show the hybrid algorithm possesses a better capability to escape from local optimums with faster convergence than the standard algorithms. The novel CGAPSO Shapley approach achieves an outage probability of 0.323324, marking a significant improvement of 60% over the outage probability achieved with conventional approach.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866809","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}
SummaryA compact, flexible, low‐profile end‐fire broadband wearable antenna operating in Ku‐band /X‐band is proposed in this manuscript for defense and satellite communications (Satcom) applications. The main objective of this work is cross‐polarization reduction by the defected ground structure (DGS), which offers a wider bandwidth. Due to its flexibility and ability to absolutely conform to the curved‐shaped human body, denim fabric is used as a substrate, whereas copper tape is used as a conductor, which allows for the integration of the antenna into garments and makes it appropriate for a wide range of wearable applications in various bands. The prototype has been developed with a size of mm3 for experimental validation. The measured results from a fabricated prototype are well matched with the simulated ones of the proposed design, which indicate a wide bandwidth of 57.35% (7.76–14 GHz) appropriate for use in applications such as defense operating from 8 to 12 GHz, satellite TV (11.7–12.2 GHz), Ku‐band downlink (10.95–11.7 GHz), Ku‐band uplink (11.7–14.5 GHz), and a high gain of 5.1 dBi. The specific absorption rate (SAR) is much below the permissible limit of 1.6 W/kg, with better radiation characteristics. Thus, the proposed antenna is more compact, and it clearly achieves a smaller footprint, larger impedance bandwidths, and a low SAR with potential prospect for Satcom and defense purposes.
{"title":"A compact wideband low‐profile all textile on/off body antenna for Satcom and defense applications","authors":"Rishabh Kumar Baudh, Sonal Sahu, Manoj Singh Parihar, Dinesh Kumar V.","doi":"10.1002/dac.5933","DOIUrl":"https://doi.org/10.1002/dac.5933","url":null,"abstract":"SummaryA compact, flexible, low‐profile end‐fire broadband wearable antenna operating in Ku‐band /X‐band is proposed in this manuscript for defense and satellite communications (Satcom) applications. The main objective of this work is cross‐polarization reduction by the defected ground structure (DGS), which offers a wider bandwidth. Due to its flexibility and ability to absolutely conform to the curved‐shaped human body, denim fabric is used as a substrate, whereas copper tape is used as a conductor, which allows for the integration of the antenna into garments and makes it appropriate for a wide range of wearable applications in various bands. The prototype has been developed with a size of mm<jats:sup>3</jats:sup> for experimental validation. The measured results from a fabricated prototype are well matched with the simulated ones of the proposed design, which indicate a wide bandwidth of 57.35% (7.76–14 GHz) appropriate for use in applications such as defense operating from 8 to 12 GHz, satellite TV (11.7–12.2 GHz), Ku‐band downlink (10.95–11.7 GHz), Ku‐band uplink (11.7–14.5 GHz), and a high gain of 5.1 dBi. The specific absorption rate (SAR) is much below the permissible limit of 1.6 W/kg, with better radiation characteristics. Thus, the proposed antenna is more compact, and it clearly achieves a smaller footprint, larger impedance bandwidths, and a low SAR with potential prospect for Satcom and defense purposes.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777325","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}
SummaryMillimeter Wave (mmWave) communication has emerged as a transformative technology at the forefront of wireless communication. One of the key challenges in harnessing the potential of mmWave technology is overcoming the increased susceptibility to propagation losses and environmental obstacles. To address these challenges, Three‐Dimensional Massive Multiple‐Input Multiple‐Output (3D Massive MIMO) systems have gained traction. The 3D aspect extends this concept by considering the elevation dimension, allowing for enhanced spatial resolution and coverage. Accurate estimation of the channel in 3D Massive MIMO scenarios is particularly challenging because of the complex propagation characteristics of mmWave signals. This paper introduces an efficient‐Aided Graph Neural Network Combining with Hierarchical Residual Learning (DPrGNN‐HrResNetL), designed specifically for beamspace Channel Estimation (CE)in mmWave‐Massive MIMO environments. The proposed model leverages deep priors and GNN mechanisms to enhance the extraction of spatial features, while hierarchical residual connections facilitate effective information flow through the network. DPrGNN enables the model to capture and understand complex spatial relationships among different antenna elements. The incorporation of deep priors provides a mechanism for leveraging prior knowledge about channel characteristics. This enhances the efficiency of the learning process, allowing the model to learn and adapt more effectively. The integration of hierarchical residual connections facilitates effective information flow through the network. This is particularly important for modeling complex dependencies within the beamspace channel data, enhancing the learning capacity of the network. The performance of the DPrGNN‐HrResNetL model is evaluated across a range of Signal‐to‐Noise Ratios (SNRs), utilizing metrics such as Normalized Mean Squared Error (NMSE) to measure the accuracy of the estimation. The outcomes underscore the resilience and efficacy of the DPrGNN‐HrResNetL approach in achieving precise CE within demanding mmWave scenarios.
{"title":"Millimeter wave–3D massive MIMO: Deep prior‐aided graph neural network combining with hierarchical residual learning for beamspace channel estimation","authors":"Haridoss Sudarsan, Krishnakumar Mahendran, Srinivasan Rathika, Subburaj Nagan Yoga Ananth","doi":"10.1002/dac.5918","DOIUrl":"https://doi.org/10.1002/dac.5918","url":null,"abstract":"SummaryMillimeter Wave (mmWave) communication has emerged as a transformative technology at the forefront of wireless communication. One of the key challenges in harnessing the potential of mmWave technology is overcoming the increased susceptibility to propagation losses and environmental obstacles. To address these challenges, Three‐Dimensional Massive Multiple‐Input Multiple‐Output (3D Massive MIMO) systems have gained traction. The 3D aspect extends this concept by considering the elevation dimension, allowing for enhanced spatial resolution and coverage. Accurate estimation of the channel in 3D Massive MIMO scenarios is particularly challenging because of the complex propagation characteristics of mmWave signals. This paper introduces an efficient‐Aided Graph Neural Network Combining with Hierarchical Residual Learning (DPrGNN‐HrResNetL), designed specifically for beamspace Channel Estimation (CE)in mmWave‐Massive MIMO environments. The proposed model leverages deep priors and GNN mechanisms to enhance the extraction of spatial features, while hierarchical residual connections facilitate effective information flow through the network. DPrGNN enables the model to capture and understand complex spatial relationships among different antenna elements. The incorporation of deep priors provides a mechanism for leveraging prior knowledge about channel characteristics. This enhances the efficiency of the learning process, allowing the model to learn and adapt more effectively. The integration of hierarchical residual connections facilitates effective information flow through the network. This is particularly important for modeling complex dependencies within the beamspace channel data, enhancing the learning capacity of the network. The performance of the DPrGNN‐HrResNetL model is evaluated across a range of Signal‐to‐Noise Ratios (SNRs), utilizing metrics such as Normalized Mean Squared Error (NMSE) to measure the accuracy of the estimation. The outcomes underscore the resilience and efficacy of the DPrGNN‐HrResNetL approach in achieving precise CE within demanding mmWave scenarios.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777323","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}
SummaryLocation‐based underwater communication applications such as strategic surveillance, disaster prevention, marine research, and mine detection have given the field of underwater wireless sensor networks (UWSN) a head start. Node localization is a prerequisite for accurate data collection, target monitoring, and network management in UWSNs. However, the unique characteristics of the underwater environment, such as signal attenuation, multipath propagation, and variable acoustic properties, pose a major challenge to effective node localization. Accurate sensor node location data is essential for successful underwater data collection, but difficult to achieve as the GPS system cannot be used in an underwater environment. In this paper, existing node localization techniques such as ALS, SLUM, MASL, SLMP, UDB, USP, etc., and recent advances such as the fusion of range‐based and range‐free techniques, the fusion of RSSI and AoA to improve localization accuracy by using directional information in addition to signal strength, and the use of optimization techniques such as PSO, COA, and WOA algorithms to improve the accuracy of the applied node localization algorithm, e.g., TP‐TSFLA, and challenges related to UWSN are discussed. Also, different localization algorithms that affect the accuracy of UWSN localization techniques have been evaluated and compared with NS2 in terms of localization error, localization coverage, energy consumption, and average communication cost metrics. In addition, this paper also provides an up‐to‐date investigation of localization techniques. Finally, the tools available for simulation are presented, followed by open research questions that need to be addressed in the localization of nodes.
{"title":"A survey on node localization technologies in UWSNs: Potential solutions, recent advancements, and future directions","authors":"Mamta Nain, Nitin Goyal, Sanjay Kumar Dhurandher, Mayank Dave, Anil Kumar Verma, Amita Malik","doi":"10.1002/dac.5915","DOIUrl":"https://doi.org/10.1002/dac.5915","url":null,"abstract":"SummaryLocation‐based underwater communication applications such as strategic surveillance, disaster prevention, marine research, and mine detection have given the field of underwater wireless sensor networks (UWSN) a head start. Node localization is a prerequisite for accurate data collection, target monitoring, and network management in UWSNs. However, the unique characteristics of the underwater environment, such as signal attenuation, multipath propagation, and variable acoustic properties, pose a major challenge to effective node localization. Accurate sensor node location data is essential for successful underwater data collection, but difficult to achieve as the GPS system cannot be used in an underwater environment. In this paper, existing node localization techniques such as ALS, SLUM, MASL, SLMP, UDB, USP, etc., and recent advances such as the fusion of range‐based and range‐free techniques, the fusion of RSSI and AoA to improve localization accuracy by using directional information in addition to signal strength, and the use of optimization techniques such as PSO, COA, and WOA algorithms to improve the accuracy of the applied node localization algorithm, e.g., TP‐TSFLA, and challenges related to UWSN are discussed. Also, different localization algorithms that affect the accuracy of UWSN localization techniques have been evaluated and compared with NS2 in terms of localization error, localization coverage, energy consumption, and average communication cost metrics. In addition, this paper also provides an up‐to‐date investigation of localization techniques. Finally, the tools available for simulation are presented, followed by open research questions that need to be addressed in the localization of nodes.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777324","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}
SummaryIn this paper, a novel strategy of video communication over a 5G platform of new radio (NR) is developed, and it is named ViNR. With the support of optimization on the ViNR quality of service (QoS) system design, we stretched the outdated R‐D optimization to a novel delay‐distortion‐rate optimization (DDRO) control method. The entire model is partitioned with two types of coding: source coding and channel coding. For source coding, we affianced the inter‐frame prediction method of independent predicted frames (IPPPP) with Lagrange multiplier optimization. Channel coding is intricate with the minimization of delay‐distortion and getting the most out of the rate using resource allocation optimization in terms of sub‐slice allocation. To perform this sub‐slice resource assignment with optimization of DDR, the isolation resource allocation is premeditated in this work to ensure the service level profile of various groups of resource slots or grids dealing with the subject of middling delay and rate. The widespread simulation results divulge that the proposed algorithm NR‐DDRO achieves better QoS parameters of delay, distortion, and rate with the metrics of end‐to‐end distortion, encoding Y‐PSNR, encoding bit rate, encoding time, end‐to‐end PSNR, optimization time, and complete computation time.
{"title":"Distortion‐less video wireless transmission in 5G new radio using delay‐distortion‐rate optimization (DDRO)","authors":"K. Maheswari, Nimmagadda Padmaja","doi":"10.1002/dac.5904","DOIUrl":"https://doi.org/10.1002/dac.5904","url":null,"abstract":"SummaryIn this paper, a novel strategy of video communication over a 5G platform of new radio (NR) is developed, and it is named ViNR. With the support of optimization on the ViNR quality of service (QoS) system design, we stretched the outdated R‐D optimization to a novel delay‐distortion‐rate optimization (DDRO) control method. The entire model is partitioned with two types of coding: source coding and channel coding. For source coding, we affianced the inter‐frame prediction method of independent predicted frames (IPPPP) with Lagrange multiplier optimization. Channel coding is intricate with the minimization of delay‐distortion and getting the most out of the rate using resource allocation optimization in terms of sub‐slice allocation. To perform this sub‐slice resource assignment with optimization of DDR, the isolation resource allocation is premeditated in this work to ensure the service level profile of various groups of resource slots or grids dealing with the subject of middling delay and rate. The widespread simulation results divulge that the proposed algorithm NR‐DDRO achieves better QoS parameters of delay, distortion, and rate with the metrics of end‐to‐end distortion, encoding Y‐PSNR, encoding bit rate, encoding time, end‐to‐end PSNR, optimization time, and complete computation time.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777326","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}
SummaryIn this paper, we investigate the performance of a rate‐splitting multiple access (RSMA)‐based intelligent reflecting surface (IRS)‐assisted uplink hybrid satellite‐terrestrial network. We consider three different scenarios based on the channel phase knowledge at the IRS, namely, the ideal, partial, and blind cases. In the ideal case, the IRS has full knowledge of both the user‐to‐IRS and IRS‐to‐satellite channel phase information. In the partial case, the IRS has only the user‐to‐IRS channel phase information. Last, in the blind case, the IRS has no any knowledge of the phase information. We assume that the user‐to‐IRS channel follows Rician fading, and the IRS‐to‐satellite channel follows the shadowed Rician fading. The closed‐form tight outage probability expressions for all three scenarios are derived. The accuracy of the derivations is confirmed by simulation results. In addition, it is shown that the performance of the RSMA‐based system is superior to those of the conventional non‐orthogonal and orthogonal multiple access‐based systems with a small number of reflecting elements at high target rates.
{"title":"Performance analysis of rate‐splitting multiple access in intelligent reflecting surface‐assisted uplink hybrid satellite‐terrestrial networks","authors":"Mehmet Can, Ibrahim Altunbas","doi":"10.1002/dac.5917","DOIUrl":"https://doi.org/10.1002/dac.5917","url":null,"abstract":"SummaryIn this paper, we investigate the performance of a rate‐splitting multiple access (RSMA)‐based intelligent reflecting surface (IRS)‐assisted uplink hybrid satellite‐terrestrial network. We consider three different scenarios based on the channel phase knowledge at the IRS, namely, the ideal, partial, and blind cases. In the ideal case, the IRS has full knowledge of both the user‐to‐IRS and IRS‐to‐satellite channel phase information. In the partial case, the IRS has only the user‐to‐IRS channel phase information. Last, in the blind case, the IRS has no any knowledge of the phase information. We assume that the user‐to‐IRS channel follows Rician fading, and the IRS‐to‐satellite channel follows the shadowed Rician fading. The closed‐form tight outage probability expressions for all three scenarios are derived. The accuracy of the derivations is confirmed by simulation results. In addition, it is shown that the performance of the RSMA‐based system is superior to those of the conventional non‐orthogonal and orthogonal multiple access‐based systems with a small number of reflecting elements at high target rates.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737926","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}
SummaryTraditional Orthogonal Multiple Access (OMA) and spectrum sharing methods struggle to provide the diverse quality of service (QoS) demands for enhanced mobile broadband (eMBB), ultra‐reliable low latency communications (uRLLC), and massive machine type communications (mMTC) leading to suboptimal performance and service quality degradation. Single‐carrier‐non‐orthogonal multiple access (SC‐NOMA) appears to be a more optimized solution. It can serve multiple users simultaneously on the same time‐frequency resources. This approach offers both enhanced spectrum efficiency and meets the QoS requirements for the coexistence of eMBB, uRLLC, and mMTC. However, SC‐NOMA has some drawbacks. Decoding a user's signal involves a complex successive interference cancellation (SIC) process that gets harder with more users causing delays and errors. Additionally, strong user signals can interfere with weaker ones, limiting the number of users per channel. In order to overcome the drawbacks associated with OMA and SC‐NOMA, this paper introduces a new method called user‐paired NOMA (hybrid NOMA). Hybrid NOMA adopts a strategic approach, employing two user pairing techniques: near‐far/far‐near (NF‐FN) and near‐near/far‐far (NN‐FF). NF‐FN pairing prioritizes users with similar signal strengths but different distances from the base station. This minimizes interference for the weaker user during SIC. NN‐FF pairing, on the other hand, groups users with similar signal strengths and proximity. This approach further simplifies SIC and minimizes potential interference altogether. The simulation results demonstrate trade‐offs between eMBB and uRLLC performance. OMA suffers with dedicated resource allocation, while SC‐NOMA balances performance but experiences interference. NN‐FF prioritizes eMBB and offers best latency, while NF‐FN prioritizes uRLLC with high spectral efficiency but suffers from higher latency. Finally, by providing a thorough grasp of how hybrid NOMA resource allocation works to improve the performance of various use cases, this research makes a significant contribution to the field of 5G spectrum optimization.
{"title":"Optimization of resource allocation in 5G networks: A network slicing approach with hybrid NOMA for enhanced uRLLC and eMBB coexistence","authors":"Rebba Chandra Sekhar, Poonam Singh","doi":"10.1002/dac.5928","DOIUrl":"https://doi.org/10.1002/dac.5928","url":null,"abstract":"SummaryTraditional Orthogonal Multiple Access (OMA) and spectrum sharing methods struggle to provide the diverse quality of service (QoS) demands for enhanced mobile broadband (eMBB), ultra‐reliable low latency communications (uRLLC), and massive machine type communications (mMTC) leading to suboptimal performance and service quality degradation. Single‐carrier‐non‐orthogonal multiple access (SC‐NOMA) appears to be a more optimized solution. It can serve multiple users simultaneously on the same time‐frequency resources. This approach offers both enhanced spectrum efficiency and meets the QoS requirements for the coexistence of eMBB, uRLLC, and mMTC. However, SC‐NOMA has some drawbacks. Decoding a user's signal involves a complex successive interference cancellation (SIC) process that gets harder with more users causing delays and errors. Additionally, strong user signals can interfere with weaker ones, limiting the number of users per channel. In order to overcome the drawbacks associated with OMA and SC‐NOMA, this paper introduces a new method called user‐paired NOMA (hybrid NOMA). Hybrid NOMA adopts a strategic approach, employing two user pairing techniques: near‐far/far‐near (NF‐FN) and near‐near/far‐far (NN‐FF). NF‐FN pairing prioritizes users with similar signal strengths but different distances from the base station. This minimizes interference for the weaker user during SIC. NN‐FF pairing, on the other hand, groups users with similar signal strengths and proximity. This approach further simplifies SIC and minimizes potential interference altogether. The simulation results demonstrate trade‐offs between eMBB and uRLLC performance. OMA suffers with dedicated resource allocation, while SC‐NOMA balances performance but experiences interference. NN‐FF prioritizes eMBB and offers best latency, while NF‐FN prioritizes uRLLC with high spectral efficiency but suffers from higher latency. Finally, by providing a thorough grasp of how hybrid NOMA resource allocation works to improve the performance of various use cases, this research makes a significant contribution to the field of 5G spectrum optimization.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141777117","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}
Hari Krishna Vana, Ramadevi Kolisetty, Balaji Narayanam
SummaryUnderwater wireless sensor networks (UWSNs) based on autonomous underwater vehicles (AUVs) have become the standard technology for underwater search tasks with the advent of new underwater information and communication technologies (ICTs). It is also vulnerable to threats and malicious attacks because of its inherent characteristics, open acoustic channel and hostile underwater environment. The purpose of this research is to develop a secure data transfer (SDF) system based on software‐defined networking (SDN) architecture with cooperative searching scheme (CSS) (SDN‐SDF‐CSS) for AUV‐based UWSN. This part employs data, local control and the primary control layer to provide a scalable SDN‐based architecture for the AUV‐based UWSN. To accomplish the underwater search operation, the data layer is primarily deployed to gather AUVs (G‐AUVs) and store AUVs (S‐AUVs). In order to schedule the AUV, the clustering process takes place based on priority ranking with respect to the average power of each cluster. Then, the CSS is developed, and it is performed in the data layer. The hierarchical localization framework (HLF) can be used to locate each AUV's location within the data layer, which is a necessary step in deploying the cooperative searching model. Finally, for an efficient data transfer, the communication model is deployed in the data layer. UWSNs are vulnerable to various malicious attacks (such as bad‐mouthing attacks, on–off attacks, blackhole attacks and wormhole attacks) because of the high bit error rate and unstable optical/acoustic channels in the underwater environment. To overcome this, an SDF technique is used, which involves isolating the attacker node from the data layer. The suggested SDN‐SDF‐CSS model is implemented on the MATLAB platform, and its performance is evaluated using various evaluation metrics, both with and without attacks. As a result, the proposed SDN‐SDF‐CSS model has achieved better performance and proved its superiority in the UWSN environment.
{"title":"SDN architecture‐based secure data transfer with cooperative searching scheme for AUV‐based underwater wireless networks","authors":"Hari Krishna Vana, Ramadevi Kolisetty, Balaji Narayanam","doi":"10.1002/dac.5909","DOIUrl":"https://doi.org/10.1002/dac.5909","url":null,"abstract":"SummaryUnderwater wireless sensor networks (UWSNs) based on autonomous underwater vehicles (AUVs) have become the standard technology for underwater search tasks with the advent of new underwater information and communication technologies (ICTs). It is also vulnerable to threats and malicious attacks because of its inherent characteristics, open acoustic channel and hostile underwater environment. The purpose of this research is to develop a secure data transfer (SDF) system based on software‐defined networking (SDN) architecture with cooperative searching scheme (CSS) (SDN‐SDF‐CSS) for AUV‐based UWSN. This part employs data, local control and the primary control layer to provide a scalable SDN‐based architecture for the AUV‐based UWSN. To accomplish the underwater search operation, the data layer is primarily deployed to gather AUVs (G‐AUVs) and store AUVs (S‐AUVs). In order to schedule the AUV, the clustering process takes place based on priority ranking with respect to the average power of each cluster. Then, the CSS is developed, and it is performed in the data layer. The hierarchical localization framework (HLF) can be used to locate each AUV's location within the data layer, which is a necessary step in deploying the cooperative searching model. Finally, for an efficient data transfer, the communication model is deployed in the data layer. UWSNs are vulnerable to various malicious attacks (such as bad‐mouthing attacks, on–off attacks, blackhole attacks and wormhole attacks) because of the high bit error rate and unstable optical/acoustic channels in the underwater environment. To overcome this, an SDF technique is used, which involves isolating the attacker node from the data layer. The suggested SDN‐SDF‐CSS model is implemented on the MATLAB platform, and its performance is evaluated using various evaluation metrics, both with and without attacks. As a result, the proposed SDN‐SDF‐CSS model has achieved better performance and proved its superiority in the UWSN environment.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737930","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}
SummaryIn today's intricate wireless communication environment, ensuring system quality demands the use of a reliable and versatile antenna system. This research article introduces a polarization reconfigurable antenna integrated with a 4 × 4 Artificial Magnetic Conductor (AMC) surface. The AMC unit cell exhibits a triple‐band reflection phase response at 1.8GHz, 4.5GHz, and 5.5GHz, demonstrating double negative metamaterial behavior. The antenna features two distinct C‐shaped metal strips connected to two PIN diodes, enabling dynamic current distribution adjustment. Consequently, the proposed antenna offers three reconfigurable states, facilitating seamless switching between dual circular polarization (left and right‐hand circular polarization) and linear polarization. With a frequency coverage ranging from 1.29 to 2.52GHz and 3.59 to 6.15GHz, the antenna boasts a maximum axial ratio (AR) bandwidth of 31.96%. Additionally, it achieves a maximum peak gain of 5.5 dB and maintains front‐to‐back ratio (FBR) values exceeding 25 dB, while recording a minimum specific absorption rate (SAR) value of 0.1059 W/kg. The integration of the AMC surface ensures enhanced performance of the antenna. Experimental results from constructed prototypes closely align with simulation outcomes, validating the effectiveness of the proposed antenna. Consequently, this antenna holds significant promise for next‐generation wireless applications.
{"title":"A miniaturized dual wide‐band polarization reconfigurable antenna integrated with artificial magnetic conductor for next‐generation wireless applications","authors":"Vellaichamy Rajavel, Dibyendu Ghoshal","doi":"10.1002/dac.5925","DOIUrl":"https://doi.org/10.1002/dac.5925","url":null,"abstract":"SummaryIn today's intricate wireless communication environment, ensuring system quality demands the use of a reliable and versatile antenna system. This research article introduces a polarization reconfigurable antenna integrated with a 4 × 4 Artificial Magnetic Conductor (AMC) surface. The AMC unit cell exhibits a triple‐band reflection phase response at 1.8GHz, 4.5GHz, and 5.5GHz, demonstrating double negative metamaterial behavior. The antenna features two distinct C‐shaped metal strips connected to two PIN diodes, enabling dynamic current distribution adjustment. Consequently, the proposed antenna offers three reconfigurable states, facilitating seamless switching between dual circular polarization (left and right‐hand circular polarization) and linear polarization. With a frequency coverage ranging from 1.29 to 2.52GHz and 3.59 to 6.15GHz, the antenna boasts a maximum axial ratio (AR) bandwidth of 31.96%. Additionally, it achieves a maximum peak gain of 5.5 dB and maintains front‐to‐back ratio (FBR) values exceeding 25 dB, while recording a minimum specific absorption rate (SAR) value of 0.1059 W/kg. The integration of the AMC surface ensures enhanced performance of the antenna. Experimental results from constructed prototypes closely align with simulation outcomes, validating the effectiveness of the proposed antenna. Consequently, this antenna holds significant promise for next‐generation wireless applications.","PeriodicalId":13946,"journal":{"name":"International Journal of Communication Systems","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737927","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}