Wireless Network Protocols and Performance Evaluation

A special issue of Electronics (ISSN 2079-9292). This special issue belongs to the section "Microwave and Wireless Communications".

Deadline for manuscript submissions: closed (31 January 2021) | Viewed by 43091

Special Issue Editors


E-Mail Website
Guest Editor
Institute for Information Transmission Problems, Russian Academy of Sciences, 127994 Moscow, Russia
Interests: design and analysis of wireless network protocols; wireless network performance evaluation methods; stochastic modeling of wireless networks based on random multiple access
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
School of Computing, Queen’s University, Kingston, ON K7L 3N6, Canada
Interests: 5G wireless sensor networks; radio resource management; edge computing; Internet of things; data-centric networks
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Telecommunications, AGH University of Science and Technology, 30-059 Krakow, Poland
Interests: wireless LANs; quality of service provisioning; novel 802.11 amendments; coexistence in unlicensed bands (e.g., Wi-Fi + LAA/NR-U); IoT and wireless SDN; modelling and simulation of wireless networks; network protocols
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Telecommunication technologies are rapidly evolving due to the rapid change of imposed functional requirements. Specifically, a quarter-century ago, the most typical problems of the time were successfully resolved by wired networks connecting mainframes. At the turn of the millennium, wireless networks were developed rapidly due to the need for the Internet access anytime and anywhere. Nowadays, we are witnessing the emergence of the Internet of Things, the ecosystem of billions of autonomous devices (sensors, controllers, robots, etc.) interacting with each other. Additionally, the future Internet will connect people and "things" and will become the Internet of Everything.

The practical development of this concept is driven by the evolution of the wireless networking technologies which are facing a number of challenges: the exponential growth of traffic, the increase in the number and density of wireless devices, and the rapid development of a new type of communications between autonomous systems involving physical objects and manufacturing processes. The development of these technologies is impossible without substantial progress in the field of modulation and coding schemes, channel access methods, QoS/QoE support and energy efficiency, the theory and recommended practice of reliable data delivery in multi-hop wireless networks (wireless mesh networks, MANET, VANET, FANET, etc.), analytical modelling, and the performance evaluation of wireless networks and their protocols.

The main aim of this Special Issue is to seek high-quality submissions focusing on the development of efficient algorithms for wireless networks and mathematical frameworks for the performance evaluation of network protocols. Topics of interest include, but are not limited to:

  • Ad-hoc, sensor, mesh, and vehicular wireless networks;
  • Energy efficiency and QoS/QoE provisioning for wireless and mobile networks;
  • 5G Systems and beyond;
  • Coexistence of wireless technologies in unlicensed bands;
  • Network virtualization and software-defined wireless networks;
  • Underground and underwater communications;
  • RFID, NFC, and machine-to-machine (M2M) communications;
  • Stochastic processes and models of wireless networks and their protocols;
  • Queues and queueing networks for wireless network performance evaluation;
  • Simulation tools for wireless network performance evaluation;
  • Testbeds and prototypes.
Prof. Dr. Andrey Lyakhov
Prof. Dr. Hossam S. Hassanein
Prof. Dr. Katarzyna Kosek-Szott
Guest Editors

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Keywords

  • wireless network protocols
  • performance evaluation
  • QoS/QoE
  • analytical models
  • simulation
  • testbeds

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Published Papers (14 papers)

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Research

34 pages, 4033 KiB  
Article
Wireless Loss Detection over Fairly Shared Heterogeneous Long Fat Networks
by Alan Briones, Adrià Mallorquí, Agustín Zaballos and Ramon Martin de Pozuelo
Electronics 2021, 10(9), 987; https://doi.org/10.3390/electronics10090987 - 21 Apr 2021
Cited by 3 | Viewed by 1976
Abstract
The quality of inter-network communication is often detrimentally affected by the large deployment of heterogeneous networks, including Long Fat Networks, as a result of wireless media introduction. Legacy transport protocols assume an independent wired connection to the network. When a loss occurs, the [...] Read more.
The quality of inter-network communication is often detrimentally affected by the large deployment of heterogeneous networks, including Long Fat Networks, as a result of wireless media introduction. Legacy transport protocols assume an independent wired connection to the network. When a loss occurs, the protocol considers it as a congestion loss, decreasing its throughput in order to reduce the network congestion without evaluating a possible channel failure. Distinct wireless transport protocols and their reference metrics are analyzed in order to design a mechanism that improves the Aggressive and Adaptative Transport Protocol (AATP) performance over Heterogeneous Long Fat Networks (HLFNs). In this paper, we present the Enhanced-AATP, which introduces the designed Loss Threshold Decision maker mechanism for the detection of different types of losses in the AATP operation. The degree to which the protocol can maintain throughput levels during channel losses or decrease production while congestion losses occur depends on the evolution of the smooth Jitter Ratio metric value. Moreover, the defined Weighted Fairness index enables the modification of protocol behavior and hence the prioritized fair use of the node’s resources. Different experiments are simulated over a network simulator to demonstrate the operation and performance improvement of the Enhanced-AATP. To conclude, the Enhanced-AATP performance is compared with other modern protocols. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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13 pages, 2375 KiB  
Communication
Stochastic Geometry-Based Analysis of Heterogeneous Wireless Network Spectral, Energy and Deployment Efficiency
by Jasmin Musovic, Vlatko Lipovac and Adriana Lipovac
Electronics 2021, 10(7), 786; https://doi.org/10.3390/electronics10070786 - 26 Mar 2021
Cited by 3 | Viewed by 2151
Abstract
For quite a while, it has been evident that homogeneous network architectures, based on cells with a uniform radiation pattern, cannot fulfill the ever increasing demand of mobile users for capacity and service quality while still preserving spectrum and energy. However, only with [...] Read more.
For quite a while, it has been evident that homogeneous network architectures, based on cells with a uniform radiation pattern, cannot fulfill the ever increasing demand of mobile users for capacity and service quality while still preserving spectrum and energy. However, only with the introduction of the Fourth Generation mobile communication networks to deal with the surging data traffic of multimedia applications, have smaller cells been widely used to break down service zone areas of macro base stations into multiple tiers, thus improving network performance, reducing traffic congestion, and enabling better management of spectrum and energy consumption in a macro network. In this paper, we present an analytical model for assessing the efficiency of bandwidth and energy usage, as well as of network deployment, taking into account overall network investment and maintenance costs. This paves the way to the improved planning of network coverage, and its capacity and reliability, thus preserving its spectrum and energy, as well as the environment. The analysis considers the downlink of an arbitrary heterogeneous cellular network by using tools of stochastic geometry that adopt the distribution of base stations in the form of a Poisson Point Process. The proposed analytical model is verified by the according software simulations using the ns-3 network simulator. The obtained results closely match the theoretically predicted values and boundaries, clearly indicating that, in all three analyzed aspects: spectral, energy, and deploymental, the efficiency of small-cell networks was higher with respect to traditional large-cell networks and increased even further for heterogeneous (two-tier in our tests) networks. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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17 pages, 3369 KiB  
Article
EVeREst: Bitrate Adaptation for Cloud VR
by Mikhail Liubogoshchev, Evgeny Korneev and Evgeny Khorov
Electronics 2021, 10(6), 678; https://doi.org/10.3390/electronics10060678 - 14 Mar 2021
Cited by 9 | Viewed by 2695
Abstract
Cloud Virtual Reality (VR) technology is expected to promote VR by providing a higher Quality of Experience (QoE) and energy efficiency at lower prices for the consumer. In cloud VR, the virtual environment is rendered on the remote server and transmitted to the [...] Read more.
Cloud Virtual Reality (VR) technology is expected to promote VR by providing a higher Quality of Experience (QoE) and energy efficiency at lower prices for the consumer. In cloud VR, the virtual environment is rendered on the remote server and transmitted to the headset as a video stream. To guarantee real-time experience, networks need to transfer huge amounts of data with much stricter delays than imposed by the state-of-the-art live video streaming applications. To reduce the burden imposed on the networks, cloud VR applications shall adequately react to the changing network conditions, including the wireless channel fluctuations and highly variable user activity. For that, they need to adjust the quality of the video stream adaptively. This paper studies video quality adaptation for cloud VR and improves the QoE for cloud VR users. It develops a distributed, i.e., with no assistance from the network, bitrate adaptation algorithm for cloud VR, called the Enhanced VR bitrate Estimator (EVeREst). The algorithm aims to optimize the average bitrate of cloud VR video flows subject to video frame delay and loss constraints. For that, the algorithm estimates both the current network load and the delay experienced by separate frames. It anticipates the changes in the users’ activity and limits the bitrate accordingly, which helps prevent excess interruptions of the playback. With simulations, the paper shows that the developed algorithm significantly improves the QoE for the end-users compared to the state-of-the-art adaptation algorithms developed for MPEG DASH live streaming, e.g., BOLA. Unlike these algorithms, the developed algorithm satisfies the frame loss requirements of multiple VR sessions and increases the network goodput by up to 10 times. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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24 pages, 3592 KiB  
Article
A Comparative Experimental Study of MIMO A&F and D&F Relay Nodes Using a Software-Defined Radio Platform
by Randy Verdecia-Peña and José I. Alonso
Electronics 2021, 10(5), 570; https://doi.org/10.3390/electronics10050570 - 28 Feb 2021
Cited by 5 | Viewed by 3067
Abstract
The relaying technologies in co-operative systems are considered a core element in actual and future wireless communications, assisting the network by enhancing its reliability and improving its capability through exploiting co-operativity. In this paper, a co-operative system testbed based on Software Defined Radio [...] Read more.
The relaying technologies in co-operative systems are considered a core element in actual and future wireless communications, assisting the network by enhancing its reliability and improving its capability through exploiting co-operativity. In this paper, a co-operative system testbed based on Software Defined Radio (SDR) through Universal Software Radio Peripherals (USRPs) and the MatlabTM software is presented. The main novelty in this development of the platform is the implementation of 4G signal features, such as Physical Downlink Shared Channel (PDSCH) and Downlink Shared Channel (DL-SCH) for transport channel coding, which is one of the main contribution of the paper. The developed Multi-Input and Multi-Output (MIMO) SDR co-operative platform is capable of developing prototypes for the Relay Nodes. More specifically, the Amplify-&-Forward (A&F)—with or without Zero Forcing (ZF) and Minimum Mean Square Error (MMSE) Pre-Equalization—and Decode-&-Forward (D&F) protocols were implemented. Both Single-Input and Single-Output (SISO) and MIMO modes are supported by our testbed. The developed A&F and D&F MIMO co-operative systems in this paper utilize Orthogonal Space-Frequency Block Codes (OSFBCs) for the transmission of data symbols from the source to the destination. Our results show that relay nodes can substantially improve the Bit Error Rate (BER) and throughput in communications between the eNodeB (eNB) and User Equipment (UE). In particular, the maximum throughput achieved by conventional MIMO A&F is 9.3Mbps at SNR=16dB, which is 4Mbps higher than throughput of MIMO Non-Co-operative. It also shows the capacity improvement when considering the pre-equalization in the A&F schemes, compared to the conventional A&F Relay Node. For example, with MIMO A&F-MMSE pattern, a value of 11.8 Mbps is achieved for SNR=16dB, which is 84.8 % of the maximum system throughput (13.95 Mbps). On the other hand, the obtained results with D&F schemes far exceed those obtained with A&F strategies, achieving the maximum performance with the 2 × 2 MIMO D&F protocol from SNR=8dB. Furthermore, this work constitutes a first stage to the implementation of a 5G New-Radio Co-operative System platform. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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13 pages, 700 KiB  
Article
Analytical Study of Periodic Restricted Access Window Mechanism for Short Slots
by Elizaveta Zazhigina, Ruslan Yusupov, Evgeny Khorov and Andrey Lyakhov
Electronics 2021, 10(5), 549; https://doi.org/10.3390/electronics10050549 - 26 Feb 2021
Cited by 8 | Viewed by 2018
Abstract
The tremendous number of devices involved in the Internet of Things is bringing new challenges to wireless networking. The more devices that transmit in a wireless network, the higher the contention for the channel. The novel Wi-Fi HaLow standard introduces a new channel [...] Read more.
The tremendous number of devices involved in the Internet of Things is bringing new challenges to wireless networking. The more devices that transmit in a wireless network, the higher the contention for the channel. The novel Wi-Fi HaLow standard introduces a new channel access mechanism called the Periodic Restricted Access Window (PRAW), which aims to reduce this contention. With this mechanism, an access point can define a series of time intervals during which only a predefined group of stations can transmit data while the other stations are forbidden to access the channel. Unfortunately, the standard does not suggest how to configure the PRAW mechanism according to scenario-specific requirements and restrictions. Many Internet of Things scenarios require the fast and low energy consumption delivery of measurement data from wireless sensors while saving channel resources for other stations that transmit, for example, multimedia traffic. Therefore, this paper studies the problem of the minimization of the channel timeshare consumed by the PRAW with restrictions on the average delay and power consumption. To solve the problem and configure the PRAW optimally, a novel analytical model is developed. The key feature of the model is the consideration of the case of short PRAW slots that allow the computational complexity to be reduced and high accuracy to be achieved. These properties make the model suitable for implementation in real devices. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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16 pages, 460 KiB  
Article
Optimal Energy Beamforming to Minimize Transmit Power in a Multi-Antenna Wireless Powered Communication Network
by Iqra Hameed, Pham-Viet Tuan, Mario R. Camana and Insoo Koo
Electronics 2021, 10(4), 509; https://doi.org/10.3390/electronics10040509 - 22 Feb 2021
Cited by 9 | Viewed by 3053
Abstract
In this paper, we study the transmit power minimization problem with optimal energy beamforming in a multi-antenna wireless powered communication network (WPCN). The considered network consists of one hybrid access point (H-AP) with multiple antennae and multiple users with a single antenna each. [...] Read more.
In this paper, we study the transmit power minimization problem with optimal energy beamforming in a multi-antenna wireless powered communication network (WPCN). The considered network consists of one hybrid access point (H-AP) with multiple antennae and multiple users with a single antenna each. The H-AP broadcasts an energy signal on the downlink, using energy beamforming to enhance the efficiency of the transmit energy. In this paper, we jointly optimize the downlink time allocation for wireless energy transfer (WET), the uplink time allocation for each user to send a wireless information signal to the H-AP, the power allocation to each user on the uplink, and the downlink energy beamforming vectors while controlling the transmit power at the H-AP. It is challenging to solve this non-convex complex optimization problem because it is numerically intractable and involves high computational complexity. We exploit a sequential parametric convex approximation (SPCA)-based iterative method, and propose optimal and sub-optimal solutions for the transmit power minimization problem. All the proposed schemes are verified by numerical simulations. Through the simulation results, we present the performance of the proposed schemes based on the effect of the number of transmit antennae and the number of users in the proposed WPCN. Through the performance evaluation, we show that the SPCA-based joint optimization solution performance is superior to other solutions. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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14 pages, 3542 KiB  
Article
An Efficient Clustering Protocol for Cognitive Radio Sensor Networks
by Vladimir Shakhov and Insoo Koo
Electronics 2021, 10(1), 84; https://doi.org/10.3390/electronics10010084 - 4 Jan 2021
Cited by 12 | Viewed by 2337
Abstract
Wireless sensor networks are considered an integral part of the Internet of Things, which is the focus of research centers and governments around the world. Clustering mechanisms and cognitive radio, in turn, are considered promising wireless network technologies for network management and spectral [...] Read more.
Wireless sensor networks are considered an integral part of the Internet of Things, which is the focus of research centers and governments around the world. Clustering mechanisms and cognitive radio, in turn, are considered promising wireless network technologies for network management and spectral efficiency, respectively. In this paper, we consider the flaws in the previously proposed network stability-aware clustering technique. In particular, we demonstrate that existing solutions do not operate properly based on the remaining energy and the quality of available common channels, even if their fusion is declared. In addition, security issues have not been sufficiently developed. We offer an approach to address these flaws. To improve protocol efficiency, the problem of parameter tuning is discussed, and a performance analysis of the proposed solution is provided as well. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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28 pages, 1113 KiB  
Article
Cache-Enabled Data Rate Maximization for Solar-Powered UAV Communication Systems
by Pham Duy Thanh, Tran Nhut Khai Hoan, Hoang Thi Huong Giang and Insoo Koo
Electronics 2020, 9(11), 1961; https://doi.org/10.3390/electronics9111961 - 20 Nov 2020
Cited by 1 | Viewed by 2180
Abstract
Currently, deploying fixed terrestrial infrastructures is not cost-effective in temporary circumstances, such as natural disasters, hotspots, and so on. Thus, we consider a system of caching-based UAV-assisted communications between multiple ground users (GUs) and a local station (LS). Specifically, a UAV is exploited [...] Read more.
Currently, deploying fixed terrestrial infrastructures is not cost-effective in temporary circumstances, such as natural disasters, hotspots, and so on. Thus, we consider a system of caching-based UAV-assisted communications between multiple ground users (GUs) and a local station (LS). Specifically, a UAV is exploited to cache data from the LS and then serve GUs’ requests to handle the issue of unavailable or damaged links from the LS to the GUs. The UAV can harvest solar energy for its operation. We investigate joint cache scheduling and power allocation schemes by using the non-orthogonal multiple access (NOMA) technique to maximize the long-term downlink rate. Two scenarios for the network are taken into account. In the first, the harvested energy distribution of the GUs is assumed to be known, and we propose a partially observable Markov decision process framework such that the UAV can allocate optimal transmission power for each GU based on proper content caching over each flight period. In the second scenario where the UAV does not know the environment’s dynamics in advance, an actor-critic-based scheme is proposed to achieve a solution by learning with a dynamic environment. Afterwards, the simulation results verify the effectiveness of the proposed methods, compared to baseline approaches. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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19 pages, 988 KiB  
Article
Joint Beamforming and Artificial Noise Optimization for Secure Transmissions in MISO-NOMA Cognitive Radio System with SWIPT
by Carla E. Garcia, Mario R. Camana and Insoo Koo
Electronics 2020, 9(11), 1948; https://doi.org/10.3390/electronics9111948 - 18 Nov 2020
Cited by 8 | Viewed by 2648
Abstract
The integration of non-orthogonal multiple access (NOMA) in cognitive radio (CR) networks has demonstrated how to enhance spectrum efficiency and achieve massive connectivity for future mobile networks. However, security is still a challenging issue due to the wireless transmission environment and the broadcast [...] Read more.
The integration of non-orthogonal multiple access (NOMA) in cognitive radio (CR) networks has demonstrated how to enhance spectrum efficiency and achieve massive connectivity for future mobile networks. However, security is still a challenging issue due to the wireless transmission environment and the broadcast nature of NOMA. Thus, in this paper, we investigate a beamforming design with artificial noise (AN) to improve the security of a multi-user downlink, multiple-input single-output (MISO) NOMA-CR network with simultaneous wireless information and power transfer (SWIPT). To further support power-limited, battery-driven devices, energy-harvesting (EH) users are involved in the proposed network. Specifically, we investigate the optimal AN, power-splitting ratios, and transmission beamforming vectors for secondary users and EH users in order to minimize the transmission power of the secondary network, subject to the following constraints: a minimum signal-to-interference-plus-noise ratio at the secondary users, minimum harvested energy by secondary users and EH users, maximum power at the secondary transmitter, and maximum permissible interference with licensed users. The proposed solution for the challenging non-convex optimization problem is based on the semidefinite relaxation method. Numerical results show that the proposed scheme outperforms the conventional scheme without AN, the zero-forcing-based scheme and the space-division multiple-access-based method. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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16 pages, 327 KiB  
Article
Evaluation of Rate Adaptation Algorithms in IEEE 802.11 Networks
by Ibrahim Sammour and Gerard Chalhoub
Electronics 2020, 9(9), 1436; https://doi.org/10.3390/electronics9091436 - 3 Sep 2020
Cited by 21 | Viewed by 5523
Abstract
Wireless technologies are being used in various applications for their ease of deployment and inherent capabilities to support mobility. Most wireless standards supports multiple data rates that may vary between few Mbps to few Gbps. Reaching the maximum supported data rate is what [...] Read more.
Wireless technologies are being used in various applications for their ease of deployment and inherent capabilities to support mobility. Most wireless standards supports multiple data rates that may vary between few Mbps to few Gbps. Reaching the maximum supported data rate is what most application seek for. Nevertheless, the choice of data rates is very closely related to the quality of communication links and their stability. IEEE 802.11 standard introduced multi-rate support, since then, a lot of research has been done on rate adaptation, dealing with the different parameters that lead to an estimation of the channel conditions and the metrics that affect the network performance. In this paper, we present some of the popular rate adaptation schemes and summarize their characteristics. We categorize them as well into different categories according to their design and functionalities in terms of the strategies that are used to estimate channel conditions and decision making. We implemented some algorithms from the different categories in the network simulator NS-3 in order to evaluate their performance under different scenarios in Ad hoc and infrastructure modes. We present the lessons learned as well as our insights for future research work that can enhance the current approaches in the literature. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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24 pages, 974 KiB  
Article
Optimizing a Secure Two-Way Network with Non-Linear SWIPT, Channel Uncertainty, and a Hidden Eavesdropper
by Pham Viet Tuan, Pham Ngoc Son, Tran Trung Duy, Sang Quang Nguyen, Van Quang Binh Ngo, Do Vinh Quang and Insoo Koo
Electronics 2020, 9(8), 1222; https://doi.org/10.3390/electronics9081222 - 29 Jul 2020
Cited by 10 | Viewed by 3068
Abstract
In this paper, the optimization of downlink beamforming vectors, uplink transmission power, and power-splitting factors is investigated for a secure two-way SWIPT network in the presence of a hidden eavesdropper and non-linear energy harvesting circuits over both perfect and imperfect channels. The eavesdropper [...] Read more.
In this paper, the optimization of downlink beamforming vectors, uplink transmission power, and power-splitting factors is investigated for a secure two-way SWIPT network in the presence of a hidden eavesdropper and non-linear energy harvesting circuits over both perfect and imperfect channels. The eavesdropper is inactive, so its channel information is not available at the base stations (BSs). The purpose of artificial noise is to create downlink interference with the hidden eavesdropper as much as possible, while satisfying the quality of service for two-way communications. For perfect downlink channels, the semidefinite relaxation (SDR) technique is exploited, and the optimal matrices are proven to satisfy rank-1 conditions, thus providing the optimal beamforming vectors. For imperfect downlink channel state information, we propose an iterative algorithm with a penalty function to obtain the approximate rank-1 matrices. On uplink, we attain the optimal transmission power for users receiving maximum ratio transmission beamforming at the BSs. Eventually, the numerical experiments show the superiority of the proposed scheme, compared to a conventional scheme, in terms of signal-to-interference-plus-noise ratio at the eavesdropper. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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20 pages, 11037 KiB  
Article
A Novel QoS-Aware A-MPDU Aggregation Scheduler for Unsaturated IEEE802.11n/ac WLANs
by Cong Lu, Bin Wu and Tianchun Ye
Electronics 2020, 9(8), 1203; https://doi.org/10.3390/electronics9081203 - 27 Jul 2020
Cited by 9 | Viewed by 2796
Abstract
Improving the quality of service (QoS) performance to support existing and upcoming real-time applications is critical for IEEE 802.11n/ac devices. The mechanisms of the media access control (MAC) layer, including the aggregate MAC protocol data unit (A-MPDU) aggregation, greatly affect the QoS performance [...] Read more.
Improving the quality of service (QoS) performance to support existing and upcoming real-time applications is critical for IEEE 802.11n/ac devices. The mechanisms of the media access control (MAC) layer, including the aggregate MAC protocol data unit (A-MPDU) aggregation, greatly affect the QoS performance in wireless local area networks (WLANs). To investigate the impact of the aggregation level on the QoS performance for real-time multimedia applications, a novel end-to-end delay model for the unsaturated settings is proposed in this paper. The presented model considers the gathering procedure of packets, queuing behaviors, and transmissions using the RTS/CTS (request to send/clear to send) mechanism on error-prone channels. Based on the model, a novel QoS-aware A-MPDU aggregation scheduler for IEEE802.11n/ac WLANs was shown to obtain better QoS performance with lower latency and less packet loss, a larger capacity to hold higher data rates, and more working nodes. The validation of the proposed model and the promotion of the proposed scheduler are well benchmarked by ns-3. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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18 pages, 1044 KiB  
Article
Energy-Aware Sensing on Battery-Less LoRaWAN Devices with Energy Harvesting
by Adnan Sabovic, Carmen Delgado, Dragan Subotic, Bart Jooris, Eli De Poorter and Jeroen Famaey
Electronics 2020, 9(6), 904; https://doi.org/10.3390/electronics9060904 - 29 May 2020
Cited by 32 | Viewed by 4771
Abstract
Billions of Internet of Things (IoT) devices rely on batteries as the main power source. These batteries are short-lived, bulky and harmful to the environment. Battery-less devices provide a promising alternative for a sustainable IoT, where energy harvested from the environment is stored [...] Read more.
Billions of Internet of Things (IoT) devices rely on batteries as the main power source. These batteries are short-lived, bulky and harmful to the environment. Battery-less devices provide a promising alternative for a sustainable IoT, where energy harvested from the environment is stored in small capacitors. This constrained energy storage and the unpredictable energy harvested result in intermittent on–off behavior of the device. Measuring and understanding the current consumption and execution time of different tasks of IoT applications is crucial to properly operate these battery-less devices. In this paper, we study how to properly schedule sensing and transmission tasks on a battery-less LoRaWAN device. We analyze the trade-off between sleeping and allowing the device to turn off between the execution of application tasks. This study allows us to properly define the device configuration (i.e., capacitor size) based on the application tasks (i.e., sensing and sending) and environmental conditions (i.e., harvesting rate). We define an optimization problem that determines the optimal capacitor voltage at which the device should start performing its tasks. Our results show that a device using LoRaWAN Class A can measure the temperature and transmit its data at least once every 5 s if it can harvest at least 10 mA of current and uses a relatively small capacitor of 10 mF or less. At harvesting rates below 3 mA, it is necessary to turn off the device between application cycles and use a larger supercapacitor of at least 140 mF. In this case, the device can transmit a temperature measurement once every 60–100 s. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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24 pages, 833 KiB  
Article
FQ-AGO: Fuzzy Logic Q-Learning Based Asymmetric Link Aware and Geographic Opportunistic Routing Scheme for MANETs
by Ali Alshehri, Abdel-Hameed A. Badawy and Hong Huang
Electronics 2020, 9(4), 576; https://doi.org/10.3390/electronics9040576 - 29 Mar 2020
Cited by 16 | Viewed by 3109
Abstract
The proliferation of mobile and IoT devices, coupled with the advances in the wireless communication capabilities of these devices, have urged the need for novel communication paradigms for such heterogeneous hybrid networks. Researchers have proposed opportunistic routing as a means to leverage the [...] Read more.
The proliferation of mobile and IoT devices, coupled with the advances in the wireless communication capabilities of these devices, have urged the need for novel communication paradigms for such heterogeneous hybrid networks. Researchers have proposed opportunistic routing as a means to leverage the potentials offered by such heterogeneous networks. While several proposals for multiple opportunistic routing protocols exist, only a few have explored fuzzy logic to evaluate wireless links status in the network to construct stable and faster paths towards the destinations. We propose FQ-AGO, a novel Fuzzy Logic Q-learning Based Asymmetric Link Aware and Geographic Opportunistic Routing scheme that leverages the presence of long-range transmission links to assign forwarding candidates towards a given destination. The proposed routing scheme utilizes fuzzy logic to evaluate whether a wireless link is useful or not by capturing multiple network metrics, the available bandwidth, link quality, node transmission power, and distance progress. Based on the fuzzy logic evaluation, the proposed routing scheme employs a Q-learning algorithm to select the best candidate set toward the destination. We implemented FQ-AGO on the ns-3 simulator and compared the performance of the proposed routing scheme with three other relevant protocols: AODV, DSDV, and GOR. For precise analysis, we considered various network metrics to compare the performance of the routing protocols. The simulation result validates our analysis and demonstrates remarkable performance improvements in terms of total network throughput, packet delivery ration, and end-to-end delay. FQ-AGO achieves up to 15%, 50%, and 45% higher throughput compared to DSDV, AODV, and GOR, respectively. Meanwhile, FQ-AGO reduces by 50% the end-to-end latency and the average number of hop-count. Full article
(This article belongs to the Special Issue Wireless Network Protocols and Performance Evaluation)
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