Green indoor optical wireless communication systems:Pathway towards pervasive deployment

The Optical Wireless Communication(OWC)offers the high capacity of optical fiber communication with the flexibility of wireless communication.Since it works in the optical region of the ElectroMagnetic(EM)spectrum,it guarantees safety and security which are critical in radio and microwave frequency communication.The principal objective of this paper is to analyze the indoor OWC systems on these guaranteed features,and safety and security are jointly denoted by the term green.The high obstacle impermeability of optical signals and their directivity strengthen the security of indoor OWC data transmission.The confidentiality and authenticity of optical wireless data can also be preserved with the Quantum Key Distribution(QKD).This paper provides a technological overview and a review of literature about the OWC system that helps to identify the challenges in the path of a ubiquitous deployment of green wireless communication systems.Significant advancements in the sources and detectors are discussed together with the coding,modulation and multiplexing techniques for making highly robust OWC links.The ubiquitous deployment of green OWC necessitates the development of optical transmitters and receivers,performance enhancement techniques,incorporation of uplink and energy harvesting abilities,and safety and security enhancement techniques.Hence,a special emphasis is placed on these aspects and their challenges towards the green implementation.Furthermore,the paper explores some significant indoor applications based on the OWC that have great impacts on the Next Generation Networks(NGN)and the Internet of Things(IoT).

Enabling Efficient Data Transmission in Wireless Sensor Networks-Based IoT Application

The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure domains like oil and gas supply,intelligent transportation,power grids,and autonomous agriculture,it is essential to guarantee the confidentiality,integrity,and authenticity of data collected and exchanged.However,the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic techniques.Consequently,designing a lightweight secure data transmission scheme is becoming essential.In this article,we propose lightweight secure data transmission(LSDT)scheme for IoT environments.LSDT consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement protocol.We design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation costs.Security and performance analysis indicates that the LSDT scheme is secure,suitable for IoT applications,and performs better in comparison to other related security schemes.

Create Your Own Data and Energy Integrated Communication Network:A Brief Tutorial and a Prototype System

In order to satisfy the ever-increasing energy appetite of the massive battery-powered and batteryless communication devices,radio frequency(RF)signals have been relied upon for transferring wireless power to them.The joint coordination of wireless power transfer(WPT)and wireless information transfer(WIT)yields simultaneous wireless information and power transfer(SWIPT)as well as data and energy integrated communication network(DEIN).However,as a promising technique,few efforts are invested in the hardware implementation of DEIN.In order to make DEIN a reality,this paper focuses on hardware implementation of a DEIN.It firstly provides a brief tutorial on SWIPT,while summarising the latest hardware design of WPT transceiver and the existing commercial solutions.Then,a prototype design in DEIN with full protocol stack is elaborated,followed by its performance evaluation.

Very Low-power Wireless Communication Technology-ZigBee

The ZigBee as the main supporting technology for the wireless sensor network has received extensive attention. Completed ZigBee protocol kits consist of the high-level application specification, the application convergence layer, the network layer, the data link layer, and the Physical (PHY) layer. The protocols of the network layer and higher ones are set up by the ZigBee Alliance, the physical layer and the Media Access Control (MAC) layer are defined by the IEEE 802.15.4 standard. The IEEE 802.15.4 physical layer simply adopts technologies of mapping from bit to symbol, conversion from symbol to chip sequence, and Offset Quadrature Phase Shift Keying (OQPSK) modulation, avoiding complicated arithmetic such as channel coding. The IEEE 802.15.4 MAC layer adopts Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) technology and supports the sleeping mode. The ZigBee enables low data transmission rate, low power consumption at low cost, and is more suitable for industry monitoring systems, sensor networks, home monitoring systems, and security systems.

Foundation Study on Wireless Big Data: Concept, Mining, Learning and Practices

Facing the development of future 5 G, the emerging technologies such as Internet of things, big data, cloud computing, and artificial intelligence is enhancing an explosive growth in data traffic. Radical changes in communication theory and implement technologies, the wireless communications and wireless networks have entered a new era. Among them, wireless big data(WBD) has tremendous value, and artificial intelligence(AI) gives unthinkable possibilities. However, in the big data development and artificial intelligence application groups, the lack of a sound theoretical foundation and mathematical methods is regarded as a real challenge that needs to be solved. From the basic problem of wireless communication, the interrelationship of demand, environment and ability, this paper intends to investigate the concept and data model of WBD, the wireless data mining, the wireless knowledge and wireless knowledge learning(WKL), and typical practices examples, to facilitate and open up more opportunities of WBD research and developments. Such research is beneficial for creating new theoretical foundation and emerging technologies of future wireless communications.

Development of a Wireless Environmental Data Acquisition Prototype Adopting Agile Practices: An Experience Report

The traditional software development model commonly named “waterfall” is unable to cope with the increasing functionality and complexity of modern embedded systems. In addition, it is unable to support the ability for businesses to quickly respond to new market opportunities due to changing requirements. As a response, the software development community developed the Agile Methodologies (e.g., extreme Programming, Scrum) which were also adopted by the Embedded System community. However, failures and bad experiences in applying Agile Methodologies to the development of embedded systems have not been reported in the literature. Therefore, this paper contributes a detailed account of our first-time experiences adopting an agile approach in the prototype development of a wireless environment data acquisition system in an academic environment. We successfully applied a subset of the extreme Programming (XP) methodology to our software development using the Python programming language, an experience that demonstrated its benefits in shaping the design of the software and also increasing productivity. We used an incremental development approach for the hardware components and adopted a “cumulative testing” approach. For the overall development process management, however, we concluded that the Promise/Commitment-Based Project Management (PB-PM/CBPM) was better suited. We discovered that software and hardware components of embedded systems are best developed in parallel or near-parallel. We learned that software components that pass automated tests may not survive in the tests against the hardware. Throughout this rapid prototyping effort, factors like team size and our availability as graduate students were major obstacles to fully apply the XP methodology.

Coal mine gas monitoring system based on wireless sensor network

Based on the nowadays＇ condition, it is urgent that the gas detection cable communication system must be replaced by the wireless communication systems. The wireless sensors distributed in the environment can achieve the intelligent gas monitoring system. Apply with multilayer data fuse to design working tactics, and import the artificial neural networks to analyze detecting result. The wireless sensors system communicates with the control center through the optical fiber cable. All the gas sensor nodes distributed in coal mine are combined into an intelligent, flexible structure wireless network system, forming coal mine gas monitoring system based on wireless sensor network.

Research on Wireless Monitoring Technology of the Well Site Environment

Based on the characteristics of wireless communication technology and Wireless Sensor Network, this paper studies the well site environmental monitoring system. The relevant hardware and software of the system are designed to monitor the well site environment, thus preventing downhole accidents. The system uses the wireless ZigBee technology as the transmission mode, and combines the virtual instrument technology to design the upper machine interface. The test results show that the system can monitor the outdoor environment in real time. When the environmental parameters exceed the set value, the corresponding location of the LabVIEW interface will send an alarm.

Designing of New Data Synchronization System

As the rapid development of Wireless Communications and the popularity of the Intelligent Terminal, data synchronization has been a social focus, meanwhile, user terminal devices are increasingly diversified, traditional synchronization technology based C/S mode has such deficiencies as insufficient amount of transmitting data and bad Real-time efficiency. It has become increasingly unable to meet the needs of future development. In this paper, we proposed and designed a new method and system by separating control with transmission to synchronize data to ensure Real-time data and improve efficiency.

Use of wireless system in healthcare for developing countries

Healthcare is one of the major applications of wireless systems that possess crucial issues. Specifically developing countries require a tow cost and reliable network with efficient protocols. The most challenging concern of Body Area Network （BAN） is heterogeneity, which requires fairness with reliability among all the network nodes. Solutions proposed for these networks either do not provide fair packet transmission or consume high energy and introduce delays. In this paper, we propose a cross layer protocol for healthcare applications meeting the requirements and challenges of the heterogeneous BAN. The protocol is also feasible for developing countries as it can be implemented over existing wireless infrastructure and provides high network reliability with energy efficiency through cooperation and adaptability. Results show that the proposed scheme improves reliability, throughput, Packet Delivery Ratio （PDR）, and energy consumption for scalable and mobile networks over conventional BAN protocols.

Energy saving for data centers using spatial multichannel optical wireless communication

Data centers are crucial elements in modern information technology.In order to implement the next generation of data centers,new challenges must be overcome.These include reducing the energy consumption,increasing the data rates,reducing the communication latency,increasing the flexibility and scalability,and reducing the maintenance time and cost.One promising way for meeting these challenges is to employ multichannel optical wireless communication as part of the data center hybrid communication network.In this paper,we analyze three technologies that could be used in this context:MIMO(Multiple-in-Multipleout),multiplexing through orbital angular momentum of light,and direct modulation through the large number of modes associated with orbital angular momentum.Our results indicate that these technologies could provide an innovative and flexible means of meeting the challenges of the next generation of data centers.

Broadband Communications for High-Speed Trains via NDN Wireless Mesh Network

With the increasing utilization of High-Speed Trains （HSTs）, the need for a reliable and high-bandwidth Internet access under high-speed mobility scenarios has become more demanding. In static, walking, and low mobility environments, TCP/IP （transmission control protocol/Internet protocol） can work well. However, TCP/IP cannot work well in high-speed scenarios because of reliability and handoff delay problems. This is mainly because the mobile node is required to maintain the connection to the corresponding node when it handovers to another access point node. In this paper, we propose a named data networking wireless mesh network architecture for HST wireless communication （NDN-Mesh-T）, which combines the advantages of Wireless Mesh Networks （WMNs） and NDN architectures. We attempt to solve the reliability and handoff delay problems to enable high bandwidth and low latency in Internet access in HST scenarios. To further improve reliability and bandwidth utilization, we propose a Direction-Aware Forwarding （DAF） strategy to forward Interest packet along the direction of the running train. The simulation results show that the proposed scheme can significantly reduce the packet loss rate by up to 51% compared to TCP/IP network architecture. Moreover, the proposed mechanism can reduce the network load, handoff delay, and data redundancy.

Development of Pandemic Monitoring System Based on Constellation of Nanosatellites

Covid-19 is a global crisis and the greatest challenge we have faced.It affects people in different ways.Most infected people develop a mild to moderate form of the disease and recover without hospitalization.This presents a problem in spreading the pandemic with unintentionally manner.Thus,this paper provides a new technique for COVID-19 monitoring remotely and in wide range.The system is based on satellite technology that provides a pivotal solution for wireless monitoring.This mission requires a data collection technique which can be based on drones’technology.Therefore,the main objective of our proposal is to develop a mission architecture around satellite technology in order to collect information in wide range,mostly,in areas suffer network coverage.A communication method was developed around a constellation of nanosatellites to cover Saudi Arabia region which is the area of interest in this paper.The new proposed architecture provided an efficient monitoring application discussing the gaps related to thermal imaging data.It reached 15.8 min as mean duration of visibility for the desired area.In total,the system can reach a coverage of 5.8 h/day,allowing to send about 21870 thermal images.

Multisensor Information Fusion for Condition Based Environment Monitoring

Destructive wildfires are becoming an annual event,similar to climate change,resulting in catastrophes that wreak havoc on both humans and the envir-onment.The result,however,is disastrous,causing irreversible damage to the ecosystem.The location of the incident and the hotspot can sometimes have an impact on earlyfire detection systems.With the advancement of intelligent sen-sor-based control technologies,the multi-sensor data fusion technique integrates data from multiple sensor nodes.The primary objective to avoid wildfire is to identify the exact location of wildfire occurrence,allowingfire units to respond as soon as possible.Thus to predict the occurrence offire in forests,a fast and effective intelligent control system is proposed.The proposed algorithm with decision tree classification determines whetherfire detection parameters are in the acceptable range and further utilizes a fuzzy-based optimization to optimize the complex environment.The experimental results of the proposed model have a detection rate of 98.3.Thus,providing real-time monitoring of certain environ-mental variables for continuous situational awareness and instant responsiveness.

A Secured Message Transmission Protocol for Vehicular Ad Hoc Networks

Vehicular Ad hoc Networks(VANETs)become a very crucial addition in the Intelligent Transportation System(ITS).It is challenging for a VANET system to provide security services and parallelly maintain high throughput by utilizing limited resources.To overcome these challenges,we propose a blockchain-based Secured Cluster-based MAC(SCB-MAC)protocol.The nearby vehicles heading towards the same direction will form a cluster and each of the clusters has its blockchain to store and distribute the safety messages.The message which contains emergency information and requires Strict Delay Requirement(SDR)for transmission are called safety messages(SM).Cluster Members(CMs)sign SMs with their private keys while sending them to the blockchain to confirm authentication,integrity,and confidentiality of the message.A Certificate Authority(CA)is responsible for physical verification,key generation,and privacy preservation of the vehicles.We implemented a test scenario as proof of concept and tested the safety message transmission(SMT)protocol in a real-world platform.Computational and storage overhead analysis shows that the proposed protocol for SMT implements security,authentication,integrity,robustness,non-repudiation,etc.while maintaining the SDR.Messages that are less important compared to the SMs are called non-safety messages(NSM)and vehicles use RTS/CTS mechanism for NSM transmission.Numerical studies show that the proposed NSM transmission method maintains 6 times more throughput,2 times less delay and 125%less Packet Dropping Rate(PDR)than traditional MAC protocols.These results prove that the proposed protocol outperforms the traditional MAC protocols.

Symbiotic Radio Systems:Detection and Performance Analysis

Symbiotic radio(SR)is an emerging green technology for the Internet of Things(IoT).One key challenge of the SR systems is to design efficient and low-complexity detectors,which is the focus of this paper.We first drive the mathematical expression of the optimal maximum-likelihood(ML)detector,and then propose a suboptimal iterative detector with low complexity.Finally,we show through numerical results that our proposed detector can obtain near-optimal bit error rate(BER)performance at a low computational cost.

TIO: A VLC-Enabled Hybrid Data Center Network Architecture

To satisfy the ever-increasing bandwidth demand of modern data centers, researchers have proposed hybrid Data Center Networks(DCNs), which employ high-bandwidth Optical Circuit Switches(OCSs) to compensate for Electrical Packet Switches(EPS). Existing designs, such as Helios and c-Through, mainly focus on reconfiguring optical devices to meet the estimated traffic requirements. However, these designs face two major challenges in their OCS-based networks, namely, the complex control mechanism and cabling problems. To solve these challenges, we propose TIO, a hybrid DCN that employs Visible Light Communication(VLC) instead of wired OCS design to connect racks. TIO integrates the wireless VLC-based Jellyfish and wired EPS-based Fat Tree seamlessly and combines the opposite and complementary characteristics, including wireless VLC direct connection and wired electrical packet switching, random graph, and Clos topology properties. To further exploit the merits of TIO, we design a hybrid routing scheme and congestion-aware flow scheduling method. Comprehensive evaluations indicate that TIO outperforms the Jellyfish and Fat Tree in both topology properties and network performance, and the flow scheduling method also evidently improves performance.

Design and optimization of VLC based small-world data centers

The visible light communication (VLC) has the potential to provide dense and fast connectivity at low cost. In this paper, we propose a novel VLC enabled Wireless Small-World Data Center (WSWDC). It employs VLC links to achieve a fully wireless data center network (DCN) across racks for the first time. The using of VLC links eliminates hierarchical switches and inter-rack cables, and thus reducing hardware investment, as well as maintenance cost. More precisely, to simplify the configuration and control operations, we propose three DCN design rationales:(1) fully-wireless, all inter-rack links are wireless;(2) easy-deployable, it is not necessary to change the existing infrastructure inside data center;(3) plug-and-play, no extra centralized control operations are required. Previous proposals, however, cannot achieve the three rationales simultaneously. To this end, we first use regular VLC links to interconnect racks as a regular grid DCN and optimize the rack placement to shorten the average path length and the network diameter. To further exploiting the benefits of VLC links, a few random VLC links are carefully introduced to update the wireless grid DCN as a wireless small-world DCN. To avoid the potential interference among VLC links, we deploy VLC transceivers at different heights on the top of each rack. In this way, VLC links would not interfere with others at each height level. Moreover, we design a greedy but efficient routing method for any pair of racks using their identifiers as inputs. Comprehensive evaluation results indicate that our WSWDC exhibits good topological properties and network performance.

True-data testbed for 5G/B5G intelligent network

Future beyond fifth-generation(B5G)and sixth-generation(6G)mobile communications will shift from facilitating interpersonal communications to supporting internet of everything(IoE),where intelligent communications with full integration of big data and artificial intelligence(AI)will play an important role in improving network efficiency and providing high-quality service.As a rapid evolving paradigm,the AI-empowered mobile communications demand large amounts of data acquired from real network environment for systematic test and verification.Hence,we build the world’s first true-data testbed for 5G/B5G intelligent network(TTIN),which comprises 5G/B5G on-site experimental networks,data acquisition&data warehouse,and AI engine&network optimization.In the TTIN,true network data acquisition,storage,standardization,and analysis are available,which enable system-level online verification of B5G/6G-orientated key technologies and support data-driven network optimization through the closed-loop control mechanism.This paper elaborates on the system architecture and module design of TTIN.Detailed technical specifications and some of the established use cases are also showcased.

Energy efficient data collection in UAV-assisted Internet of things:trajectory planning and aerodynamic-based attitude control

Due to its inherent characteristics of flexible mobility,unmanned aerial vehicle(UAV) is exploited as a cost-efficient mobile platform to assist remote data collection in the 5 th generation or beyond the 5 th generation(5 G/B5 G) wireless systems.Compared with static terrestrial base stations,the line-of-sight(LoS) link between UAVs and ground nodes are stronger due to their flexibility in three-dimensional(3 D) space.Due to the fact that flexible mobility of UAVs requires high propulsion power,the limited on-board energy constrains the performance of UAV-assisted data collection.It is worth noting that UAVs can be categorized into rotary-wing UAVs and fixed-wing UAVs,either has its own characteristics in propulsion energy consumption.In this article,a comprehensive review of state-of-art studies on trajectory design schemes for rotary-wing UAVs,as well as aerodynamic-aware attitude control strategies for fixed-wing UAVs was provided.Then,two case studies for energy-efficient data collection using rotary-wing UAVs and fixed-wing UAVs were presented,respectively.More specifically,an age-energy aware data collection scheme was demonstrated for rotary-wing UAVs to optimize the timeliness of collected data.Moreover,an aerodynamic-aware attitude control strategy for fixed-wing UAVs was also demonstrated under data collection requirements.