Heterogeneous Wireless Communication Research Articles

Comprehensive Assessment of Context-Adaptive Street Lighting: Technical Aspects, Economic Insights, and Measurements from Large-Scale, Long-Term Implementations.

This paper addresses the growing importance of efficient street lighting management, driven by rising electricity costs and the need for municipalities to implement cost-effective solutions. Central to this study is the UNI 11248 Italian regulation, which extends the European EN 13201-1 standard introduced in 2016. These standards provide guidelines for designing, installing, operating, and maintaining lighting systems in pedestrian and vehicular traffic areas. Specifically, the UNI 11248 standard introduces the possibility to dynamically adjust light intensity through two alternative operating modes: (a) Traffic Adaptive Installation (TAI), which dims the light based solely on real-time traffic flow measurements; and (b) Full Adaptive Installation (FAI), which, in addition to traffic measurements, also requires evaluating road surface luminance and meteorological conditions. In this paper, we first present the general architecture and operation of an FAI-enabled lighting infrastructure, which relies on environmental sensors and a heterogeneous wireless communication network to connect intelligent, remotely controlled streetlights. Subsequently, we examine large-scale, in-field FAI infrastructures deployed in Vietnam and Italy as case studies, providing substantial measurement data. The paper offers insights into the measured energy consumption of these infrastructures, comparing them to that of conventional light-control strategies used in traditional installations. The measurements demonstrate the superiority of FAI as the most efficient solution.

INTERCONNECTION SCHEME FOR A MULTIPROTOCOL HETEROGENEOUS WIRELESS COMMUNICATION SYSTEM IN A CIVIL AIRPORT

In the movement area of an airport, the wireless communication system is built to satisfy the communication requirements of mobile stations (MSs), which include aircraft, vehicles, staff, passengers, and sensors. However, the actual airport wireless communication system is a heterogeneous wireless network with multiple individual wireless communication systems. In this paper, we design a multiprotocol base station (MPBS) to realize the access and interconnection of the MSs with different protocols. In addition, a direct forwarding scheme of MPBS is proposed to improve the performance of transmissions from one MS to another. Third, a priority order transmission scheme, which can reduce the end-to-end delay of important data, is proposed for direct forwarding MPBS. Simulation results show that the proposed direct forwarding MPBS scheme can improve the transmission performance of interactive data and reduce the load of the core network.

MPoR: A Modified Consensus for Blockchain-Based Internet of Vehicles

Ride-sharing services, such as ride-hailing and carpooling, have become attractive travel patterns for worldwide users. Due to the high dynamic topology, heterogeneous wireless communication mode, and centralization, the Internet of Vehicles (IoV) is much more vulnerable to security issues such as privacy theft, single point of failure, data island, and unauthorized access, resulting in great security risks, while ride-sharing services provide convenience. Blockchain technology used to solve the security problems of the IoV has become a current research hotspot, including authentication and privacy protection. Nevertheless, the existing algorithms still face challenges such as large amount of computation, low throughput, low scalability, consensus, and node security. Achieving an efficient, lightweight, and scalable secure blockchain–based IoV system still needs to be solved urgently. In this paper, we propose an effective consensus algorithm called Modified Proof of Reputation (MPoR). Firstly, by using the average network access time of the whole network nodes as the filtering threshold, the number of consensus nodes can be controlled adaptively. Then, a new multiweight reputation algorithm is proposed to quantify the reputation value of nodes, so as to detect and eliminate malicious nodes in the consensus node pool. Theoretical analysis and extensive simulation experiments reflect that under the IoV scenario, MPoR can adaptively select the number of consensus nodes, to effectively improve the consensus efficiency. When malicious nodes are less than 1/3 of the total nodes in the network, MPoR can effectively resist latent attack and collusive attack and has strong robustness.

Revenue Maximization Through Cell Switching and Spectrum Leasing in 5G HetNets

Even though dynamic cell switching is a prominent approach for energy optimization in heterogeneous wireless communication networks, it results in spectrum under-utilization as the spectrum originally occupied by the base stations that are turned off remain dormant. In order to make the businesses of primary network (PN) operators, who hold the spectrum license, more profitable and sustainable as well as to avoid spectrum under-utilization, this dormant spectrum can be leased to the secondary network (SN) operators who cannot afford to purchase the spectrum license. In this study, first, the cell switching problem, which solely focuses on the amount of energy saved, is translated to a problem of revenue maximization by including the spectrum leasing concept and converting the energy saving to monetary saving from reduced electricity bills. In this regard, two spectrum demand scenarios are considered for the SN operator: delay tolerant (DT), for non-real time applications, and non-delay tolerant (NDT), for real time applications. Then, a cell switching and spectrum leasing framework based on simulated annealing algorithm is developed to maximize the revenue of the PN while respecting the quality-of-service constraints. The simulation results reveal that the DT spectrum demand is more beneficial to both PN and SN operators as it results in greater revenue for the former while the latter is able to access more spectrum to meet higher service demands. This finding suggests that if the application can tolerate delays, then it makes more sense for both PN and SN to adopt the DT scenario. In addition, it is observed that the performance of the proposed framework is very close to that of the optimal solution with a significant reduction in the computation complexity.

Spoofing Attack Detection Using Machine Learning in Cross-Technology Communication

Cross-technology communication (CTC) technique can realize direct communication among heterogeneous wireless devices (e.g., WiFi, ZigBee, and Bluetooth in the 2.4 G ISM band) without gateway equipment for forwarding, which makes heterogeneous wireless communication more convenient and greatly reduces communication costs. However, compared with the traditional homogeneous network model, CTC technique also makes it easier to implement spoofing attacks in heterogeneous networks. WiFi devices with long communication distances and sufficient energy supply can directly launch spoofing attacks against ZigBee devices, which brings severe security concerns for heterogeneous wireless communications. In this paper, we focus on the CTC spoofing attack, especially spoofing attacks from WiFi to ZigBee and propose a machine learning-based method to detect spoofing attacks for heterogeneous wireless networks by using physical-layer information. First, we model the received signal strength (RSS) data of legitimate ZigBee devices to construct a one-class support vector machine (OSVM) classifier for detecting CTC spoofing attacks depending on the obtained training samples. Then, we simulated CTC spoofing attacks in a live testbed and evaluated the performance of our detection method. Results show that our approach is highly effective in spoofing detection. Even if the distance between the legitimate ZigBee device and WiFi attacker is near each other (i.e., less than 2 m) and does not require a large number of samples, the detection rate and precision of our method are both over 90%. Finally, we employ the OSVM classifier to obtain samples of spoofing attacks and then explore using SVM to further improve the performance of the classifier.

A Compact High Gain Multiband Bowtie Slot Antenna with Miniaturized Triangular Shaped Metallic Ground Plane

This paper presents a new compact, high gain and multiband planar bowtie slot antenna. The antenna structure comprises of dielectric substrate, copper conducting sheet, fillet triangular-shaped slots, and a chamfered metallic ground plane. The proposed antenna model is fed with the 50 Ω standard grounded coplanar waveguide (GCPW) feedline. The designed antenna is low profile with compact dimensions of 0.379λ×0.186λ×0.012λ at 2.39 GHz frequency. Stable multi-resonant behavior of frequencies is obtained with the material selection, slots dimensions and position. Moreover, the parametric study has been carried out in order to validate the frequency tuning mechanism and impedance matching control. The novelty of designed antenna lies in high performance features which have been achieved with ultra-compact (0.039λ×0.022λ) modified triangular shaped metallic ground plane. The proposed antenna is fabricated and experimentally verified. The antenna key features in terms of return loss, surface current distribution, peak gain, radiation efficiency and radiation patterns have been analyzed and discussed. The designed radiator exhibits the excellent performance including strong current density, peak realized gain of 6.3 dBi, 95% radiation efficiency, wide fractional bandwidth of 39.5% and good radiation characteristics at in-band frequencies. The simulation and measured results are in good agreement and hence make the proposed antenna a favorable candidate for the advanced heterogeneous wireless communication applications.

Guest Editorial: Introduction to the Special Section on Heterogeneous Communications Networks

The papers in this special section focus on heterogeneous communication networks. These networks, consisting of terrestrial mobile networks, satellite networks, IoT, WiFi, and etc., is a promising technique to meet the challenges in future mobile communications. Heterogeneous network resources are expected to cooperate with each other to support more efficient data transmissions and also provide more reliable services. However, current network architectures cannot efficiently exploit the benefit of heterogeneous wireless communication networks. Considering the deficiency in existing wireless networks nowadays, the most substantial amount of future system performance gains will be obtained by means of heterogeneous network infrastructure densification. Therefore, the heterogeneous communication networks should be deeply investigated to realize the full benefits of each of them.

Employing Unmanned Aerial Vehicles for Improving Handoff Using Cooperative Game Theory

Heterogeneous wireless networks that are used for seamless mobility are expected to face prominent problems in future fifth generation (5G) cellular networks. Due to their proper flexibility and adaptable preparation, remote-controlled unmanned aerial vehicles (UAVs) could assist heterogeneous wireless communication. However, the key challenges of current UAV-assisted communications consist in having appropriate accessibility over wireless networks via mobile devices with an acceptable Quality of Service grounded on the users’ preferences. To this end, we propose a novel method based on cooperative game theory to select the best UAV during handover process and optimize handover among UAVs by decreasing the i) end-to-end delay, ii) handover latency, and iii) signaling overheads. Moreover, the standard design of software-defined network with media-independent handover is used as forwarding switches in order to obtain seamless mobility. Numerical results derived from the real data are provided to illustrate the effectiveness of the proposed approach in terms of number of handovers, cost, and delay.

Towards Distributed SDN: Mobility Management and Flow Scheduling in Software Defined Urban IoT

The growth of Internet of Things (IoT) devices with multiple radio interfaces has resulted in a number of urban-scale deployments of IoT multinetworks, where heterogeneous wireless communication solutions coexist (e.g., WiFi, Bluetooth, Cellular). Managing the multinetworks for seamless IoT access and handover, especially in mobile environments, is a key challenge. Software-defined networking (SDN) is emerging as a promising paradigm for quick and easy configuration of network devices, but its application in urban-scale multinetworks requiring heterogeneous and frequent IoT access is not well studied. In this paper we present UbiFlow, the first software-defined IoT system for combined ubiquitous flow control and mobility management in urban heterogeneous networks. UbiFlow adopts multiple controllers to divide urban-scale SDN into different geographic partitions (assigning one controller per partition) and achieve distributed control of IoT flows. A distributed hashing based overlay structure is proposed to maintain network scalability and consistency. Based on this UbiFlow overlay structure, the relevant issues pertaining to mobility management such as scalable control, fault tolerance, and load balancing have been carefully examined and studied. The UbiFlow controller differentiates flow scheduling based on per-device requirements and whole-partition capabilities. Therefore, it can present a network status view and optimized selection of access points in multinetworks to satisfy IoT flow requests, while guaranteeing network performance for each partition. Simulation and realistic testbed experiments confirm that UbiFlow can successfully achieve scalable mobility management and robust flow scheduling in IoT multinetworks; e.g., 67.21 percent throughput improvement, 72.99 percent reduced delay, and 69.59 percent jitter improvements, compared with alternative SDN systems.

Achieving sustainability through smart city applications: protocols, systems and solutions using IoT and wireless sensor network

Smart city applications is not just limited to the use of technology in building better cities and improving the citizens’ quality of lives. In reality, it is capable of building comprehensive solutions for the development of sustainable communities, irrespective of being urban or rural. Different communities will have their own dynamics and complexity, some communities are widespread and distributed, while some are more dense and concentrated. Each of these characteristics can either become an advantage or a barrier while developing solutions for these communities, which can be addressed with the proper use of technology. Internet of things (IoT) and wireless sensor networks (WSN), are the technologies in particular that can help in building comprehensive solutions for creating sustainable communities as they have a wide variety of applications such as disaster management, healthcare, energy, water, surveillance, structural health monitoring and environmental monitoring. This paper describes about four major research works in smart city application areas such as (a) design and deployment of an IoT system for early warning of landslides, (b) heterogeneous wireless communication design and optimization for enabling real-time management of interoperation of heterogeneous devices and data services in a hybrid electrical network, (c) development of (low-cost) IoT sensors for remote patient monitoring and (d) design and deployment of systems and solution for providing mobile offshore connectivity for fishing vessels—internet over sea. This paper details the current state of the art, challenges to be solved, and the methodology that we have adapted for developing solutions in all these research areas. The extensive research in IoT, WSN and its applications has resulted in receiving the award, titled “World Center of Excellence in Landslide Risk Reduction” and five patents, namely (a) network-based system for predicting landslides and providing early warnings (b) mobile infrastructure for coastal region offshore communications and networks (c) wearable wireless tongue controlled devices (d) Systems, methods, and devices for remote health monitoring and management (e) Systems, methods, and devices for remote health monitoring and management using internet of things sensors

Effective Bandwidth Prediction through Statistical Technique over Heterogeneous Networks

Real time Streaming Media (Video Streaming) applications are mostly popular on the mobiles and computers using Internet. Due to higher demand of video streaming through wireless network and mobile devices, video are being transmitted through various heterogeneous networks so as to efficiently deliver to the clients devices. This has resulted in the lower quality of real time video, since real time streaming media has quality of parameter requirements like high bandwidth, low packet loss ratio, higher delay and jitter. Streaming media such as video through heterogeneous networks has more challenges due to unreliable wireless networks and device mobility; moreover bandwidth, delay and loss are unknown in advance and are unbounded. In this paper, effective bandwidth prediction through statistical technique over heterogeneous wireless communication networks is proposed. Statistical technique offers computationally efficient bandwidth prediction with reasonably better accuracy. Especially with mobile devices with limited computational power and battery life, necessitates better bandwidth prediction with efficient but computationally simpler algorithms. Bandwidth predictions assist in selecting effective network for video streaming when various heterogeneous networks are available. Detailed bandwidth prediction algorithm is presented with use of quality of service (QoS) parameters data sets available online.

Enabling Generic Wireless Coexistence Through Technology-Agnostic Dynamic Spectrum Access

Every year that passes, new standardized and proprietary wireless communication technologies are introduced in the market that seeks to find its place within the already highly congested spectrum. Regulation bodies all around the globe are struggling to keep up with the continuously increasing demand for new bands to offer to specific technologies, some of them requiring by design an exclusive frequency band in order to operate efficiently. Even wireless bands offered for public or scientific usage like the ISM bands are becoming the natural habitat of multiple wireless technologies that seek to use or “abuse” them in order to provide even more bandwidth to their offered applications. Wireless research teams targeting heterogeneous wireless communication coexistence are developing techniques for enabling one-to-one coexistence between various wireless technologies. Can such an exhaustive approach be the solution for N wireless technologies that wish to operate in the same band? We believe that a one-to-one approach is inefficient and cannot lead to a generic coexistence paradigm, applicable to every existing or new wireless communication technology that will arise in the future. Can another approach provide a more generic solution in terms of frequency reuse and coexistence compared to the one-dimensional frequency separation approach commonly used in commercial deployments today. Can such a generic approach provide a simple and easily adoptable coexistence model for existing technologies? In this paper we present a new generic medium sharing model that solves the huge coexistence problems observed today in a simple and efficient way. Our approach is technology-agnostic and compatible with all existing wireless communication technologies and also has the capability to support emerging ones with minimum overhead.

Automated Self-Optimization in Heterogeneous Wireless Communications Networks

Traditional single-tiered wireless communications networks cannot scale to satisfy exponentially rising demand. Operators are increasing capacity by densifying their existing macro cell deployments with co-channel small cells. However, cross-tier interference and load balancing issues present new optimization challenges in channel sharing heterogeneous networks (HetNets). One-size-fits-all heuristics for allocating resources are highly suboptimal, but designing ad hoc controllers requires significant human expertise and manual fine-tuning. In this paper, a unified, flexible, and fully automated approach for end-to-end optimization in multi-layer HetNets is presented. A hill climbing algorithm is developed for reconfiguring cells in real time in order to track dynamic traffic patterns. Schedulers for allocating spectrum to user equipment are automatically synthesized using grammar-based genetic programming. The proposed methods for configuring the HetNet and scheduling in the time–frequency domain can address ad hoc objective functions. Thus, the operator can flexibly tune the tradeoff between peak rates and fairness. Far cell edge downlink rates are increased by up to 250% compared with non-adaptive baselines. Alternatively, peak rates are increased by up to 340%. The experiments illustrate the utility and future potential of natural computing techniques in software-defined wireless communications networks.

Optimized Cell Planning for Network Slicing in Heterogeneous Wireless Communication Networks

We propose a cell planning scheme to maximize the resource efficiency of a wireless communication network while considering quality-of-service requirements imposed by different mobile services. In dense and heterogeneous cellular 5G networks, the available time-frequency resources are orthogonally partitioned among different slices, which are serviced by the cells. The proposed scheme achieves a joint optimization of the resource distribution between network slices, the allocation of cells to operate on different slices, and the allocation of users to cells. Since the original problem formulation is computationally intractable, we propose a convex inner approximation. Simulations show that the proposed approach optimizes the resource efficiency and enables a service-centric network design paradigm.

Bandwidth Efficiency and Service Adaptiveness Oriented Data Dissemination in Heterogeneous Vehicular Networks

Heterogeneous network resources are expected to cooperate with each other to support efficient data services in vehicular networks. However, current data scheduling methods cannot efficiently exploit the benefit of heterogeneous wireless communication interfaces in vehicular networks. In this paper, we propose a software-defined network based service architecture, which enables the scheduler to manage heterogeneous network resources in a centralized way. We analyze the heterogeneity of both data items and networks in terms of data sizes and network features (e.g., cost, transmission rate, coverage, etc.), respectively. On this basis, we formulate a data broadcast and network interface selection (DBNIS) problem, which aims to minimize both the service delay and the network access cost. To tackle the problem efficiently, we propose a coding-assisted multiobjective evolutionary algorithm (CMOEA), which consists of two components: packet encoding and network interface selection. Specifically, for packet encoding, we first develop a packet-size based random linear encoding (PRLE) technique to improve bandwidth efficiency. Then, we theoretically analyze the performance bound of PRLE. For network interface selection, we propose a multiobjective algorithm for network interface selection to adaptively satisfy dynamic requirements with respect to service delay and network access cost by deriving a set of pareto-solutions. Finally, we build the simulation model and implement CMOEA for performance evaluation. The comprehensive simulation results demonstrate the superiority of CMOEA under a wide range of scenarios.

Heterogeneous vehicular communications: A comprehensive study

Vehicular communications have developed rapidly contributing to the success of intelligent transportation systems. In VANET, continuous connectivity is a huge challenge caused by the extremely dynamic network topology and the highly variable number of mobile nodes. Moreover, message dissemination efficiency is a serious issue in traffic effectiveness and road safety. The heterogeneous vehicular network, which integrates cellular networks with DSRC, has been suggested and attracted significant attention recently. VANET-cellular integration offers many potential benefits, for instance, high data rates, low latency, and extended communication range. Due to the heterogeneous wireless access, a seamless handover decision is required to guarantee QoS of communications and to maintain continuous connectivity between the vehicles. On the other hand, VANET heterogeneous wireless networks integration will significantly help autonomous cars to be functional in reality. This paper surveys and reviews some related studies in the literature that deals with VANET heterogeneous wireless networks communications in term of vertical handover, data dissemination and collection, gateway selection and other issues. The comparison between different works is based on parameters like bandwidth, delay, throughput, and packet loss. Finally, we outline open issues that help to identify the future research directions of VANET in the heterogeneous environment.

Spectrum Sharing Policy: Interoperable Communication and Information Sharing for Public Safety

Among Public Safety Communication (PSC) systems there is a mounting concern over interoperability. To mitigate such interoperability issues, the Department of Homeland Security (DHS) created the National Emergency Communications Plan (NECP) to guide the implementation of a nationwide PSC system; however, this system hinges on the effective integration of heterogeneous wireless communication systems, efficient spectrum sharing, and ability to overcome other key policy or management obstacles. To explore these topics further, this paper reviews government documents pertaining to interoperability, wireless communication, and spectrum sharing. Within the context of PSC, the study aims to identify key obstacles; understand how government documents address policies and regulations related to the wireless communication, interoperability, and spectrum sharing; and, determine how to address overload of wireless communication and spectrum during a major disaster situation.

A Multi-Criteria Decision Framework for network selection over LTE and WLAN

The most appealing topic for next generation wireless networks – 5G and upcoming generations – is the vertical handover, as many heterogeneous wireless communication technologies have been introduced recently to fulfil the needs of mobile users under all circumstances. Especially with the growing applications that are greedy in terms of Quality of Service (QoS). Thus, being Always Best Connected (ABC) remains a difficult task to achieve.The purpose of this article is to tackle the network selection issue levering a combination of Multi-Criteria Decision Making (MCDM) methods to ensure that appropriate network is selected for a certain type of traffic and considering a number of QoS metrics that due to their interdependency, a weight distribution phase is required. To ascertain thoroughly the weights of QoS metrics impacting the decision for each application, Analytical Hierarchy Process (AHP) is generally applied. But its classical form comes with biased rules that are dealt with through an enhanced version FAHP (Fuzzy AHP) that has proven its performance when combined with other well reputed ranking methods, namely: ”Multiplicative Exponential Weighting (MEW)”, ”Simple Additive Weighting (SAW)”, ”Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS)” and ”VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR)”.The implementation and simulation experiments in LTE and WLAN environments using Network Simulator NS3 are presented in order to evaluate the reviewed algorithms focusing on Packet Delay and Packet Loss Rate as key selection criteria. The empirical results show that FAHP algorithms over perform the classical AHP ones. The most suitable algorithms combination will be assessed and suggested for each type of traffic.

Double-ring multiband microstrip patch antenna with parasitic strip structure for heterogeneous wireless communication systems

In this paper, a novel design of compact Coplanar Waveguide-fed planar monopole antenna with enhanced bandwidth and multiband characteristics has been proposed. Two rectangular rings have been incorporated in a rectangular patch to obtain multiband operation for Wireless Local Area Network (WLAN) (2.4/5.2/5.8 GHz) and Worldwide Interoperability for Microwave Access (WiMAX) (2.3/2.5/5.5 GHz) bands. A parasitic strip and meandering along with double-ringed structure have been used to achieve enhanced impedance bandwidth in WLAN (from 2.26 to 3.03 GHz) and WiMAX (from 4.48 to 6.85 GHz) bands. The parametric analysis is carried out to study effect of varying dimensions on antenna performance. The proposed antenna is optimized and prototype is designed and fabricated. Simulated and measured radiation patterns in elevation and azimuthal planes are also observed. The antenna shows significant gain of 7.33 dBi at 6.54 GHz frequency.

A novel downlink semi-persistent packet scheduling scheme for VoLTE traffic over heterogeneous wireless networks

Long-term evolution (LTE) is becoming the first choice of mobile network operators (MNOs) when constructing a wireless network infrastructure because of its high data rate, high throughput, and low latency. These significant advancements are necessary for satisfying the delivery of a wide-range of mobile applications and managed network resources. However, deploying a new LTE network or a transition from current legacy cellular networks to LTE can take several years to roll out. In the meantime, working in a heterogeneous wireless communication network looks inevitable. This paper investigates Voice over LTE (VoLTE) Quality of Service (QoS) under a heterogeneous wireless communication scenario. The contributions of this paper are twofold. First, a novel downlink (DL) semi-persistent scheduling scheme is proposed to reduce VoLTE end-to-end delay and increase system capacity. Second, an extensive network simulation model has been designed and implemented to evaluate the proposed scheme. The performance of the proposed scheme is compared with the performance of two relevant and well-known DL packet scheduling methods. The simulation results confirm that the proposed scheme is able to reduce VoLTE end-to-end delay and achieve a better system capacity than current methods, and maintain the desired VoLTE QoS.