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This paper presents a ray tracing approach to optimise the position of a relay in a static environment such that the signal-to-noise ratio (SNR) is maximised at the receiver. The underlying principles behind the ray tracing wireless channel model are summarised. An implementation of a ray tracing algorithm is developed in MATLAB to calculate the channel state information (CSI) of a relay-assisted...
In a wireless body area networks (WBAN) with integrated sensor hubs, the proposed MAC protocol is a TDMA-based schedule used in active superframe interleaving and beacon shifting defined by the IEEE 802.15.6 standard. It considers the human dynamics and traffic information to meet the different QoS requirements of each sensor, improve bandwidth utilization and reduces packet collisions within networks...
We propose a new caching concept in which wireless nodes in Device-to-Device (D2D) network can cache the initialsegments of the popular video files and may share to users in their proximity upon request. We term this approach as Bootstrapping-D2D (B-D2D) system. Our findings suggest that caching only initial-segments creates a large pool of popular files, thus improving the probability of availability...
Aiming at meeting the application requirements of low time delay and packet lose rate of wireless HD video PAN, an Video Point Coordination Function (VPCF) mechanism for MAC layer scheduling based on IEEE 802.11 PCF is proposed in this paper. TSP service periods are allocated to video station, which has burst video frames to transfer, and the number of needed CBAP (Slot Period Transmission), is evaluated...
A variety of wireless communication links today, such as HSPA+ access in high speed trains, balloon-based aerial wireless networks and satellite Internet connections have high loss rates. In such environments, Multipath TCP (MPTCP) offers a robust solution compared to regular TCP. However, MPTCP and existing schedulers suffer from performance degradation for both constant bit rate (CBR) and bulk traffic...
The research on the future high-speed communication systems has already reached the critical point with better continuous transmission and higher system capacity especially for the on-board users in the high-speed trains. However, due to the inflexible architecture of current cellular networks where Internet access schemes served by multiple Internet Service Providers lack effective coordination,...
Designing wireless industrial communication for factory automation is a serious task because novel radio systems have to compete with well established wired fieldbus solutions. The requirements to achieve equivalent reliability and latencies impose challenging demands on design and implementation. In this paper, we propose a hardware accelerator for highly adaptive and parallel medium access allowing...
There are lots of efforts to improve interworking architectures for the purpose of offloading cellular traffic via complementary wireless technologies. Some offer a specific feature and others work on a generic one, and yet there is a need for feature-rich interworking architecture for offloading purposes. This paper proposes a fully integrated, hybrid and Quality of Service aware interworking architecture...
An experimental set-up and procedure for emulating realistic fading channels in a reverberation chamber is described in this contribution. Of particular interest is the generation of power delay profiles of urban-macro and -micro channels defined in the 3GPP Spatial-Channel-Model-Extended (SCME). The input signal to the chamber is generated by convolving a rectangular pulse with delay taps using a...
Recently, 5G systems started to explore the usage of mmWave bands both for access and backhaul. Cellular systems operating at such frequencies would achieve a significantly higher capacity than current systems due to the large frequency block available. Due to the propagation characteristics, highly directional mmWave links may frequently switch between Line-of-sight, Non Line-of-sight and outage...
Pervasive networks formed spontaneously by wireless mobile devices capable of ad hoc communication make it possible to get services from these devices, and to compose them dynamically so as to provide people with new and more sophisticated application services. Discovering, invoking and composing services in such networks are challenging tasks, due to the numerous and unpredictable connectivity disruptions...
Although IEEE 802.11p technology is standardized for road safety and efficiency applications, the channel congestion problem is its key weakness necessitating distributed congestion control (DCC) algorithms on different layers of the communication stack. In this paper, we propose DCC-enabled Contention based Forwarding scheme targeting multi-hop dissemination of Decentralised Event Notification Messages...
With the increment in users' data demand and the emergence of applications with stringent Quality of Service requirements, important improvements in cellular network architecture need to be made. In this paper we explore the symbiosis of three key communication technologies in 5G: Device-to-Device communications, 60 GHz unlicensed band transmissions and adaptive beamforming techniques. It provides...
With the rapid increasing scale of Intelligent Transportation System (ITS) and vehicular network, our quality of life are significantly improved, especially traveling in urban area. To supply a large amount of real-time ITS applications, such as navigation and automatic driving, aggregation delay should be controlled in a small range so that more data might be dropped during aggregation. State-of-the-art...
Millimeter wave (mmWave) communication has become a promising key technology of the fifth generation (5G) communication systems, and gained extensive interests. In this paper, we examine 60 GHz mmWave channels in an indoor office environment by means of ray tracing method. Based on geometrical optic (GO) and uniform theory of diffraction (UTD), ray tracing method uses computer simulation to approximate...
In this paper, we propose a scheme in which a communication relay unmanned aerial vehicle (UAV) estimates the distribution of the terminals and selects the optimal relay position for autonomous maneuvering. In order to accomplish mission success, warfighters on the battlefield must communicate with their commander all the time. Autonomous maneuvering of a relay UAV using the proposed scheme will support...
To satisfy the requirement of increasing mobile traffic, heterogeneous networks (HetNets) will be deployed for the fifth generation (5G) mobile communications systems. Since the deployment of base stations (BSs) in HetNets is generally dense and random, stochastic geometry has increasingly been used to analyze the performance of HetNets. Most of the existing work is based on Poisson point processes...
Wireless multimedia sensor networks (WMSNs) require data to be communicated timely and reliably. However, radio transmission errors incurred by wireless channel make it difficult to achieve these qualities simultaneously. To provide good quality of service (QoS) of WMSNs, parameters associated with the WMSNs need to be studied completely and best tradeoff needs to be made. To characterize the delay-reliability...
In recent years, video streaming traffic has increased exponentially over the Internet. This can be observed through the emergence of various video on demand sites such as Netflix, Amazon movies and others. In parallel, IEEE 802.11 (WiFi) technology has been deployed extensively from home to public areas. Although significant research has been done to address issues on video streaming through WiFi...
Smart grid (SG) has been recognized as a promising solution to manage and distribute electricity in the next generation power systems. The large number of devices in power systems make the wired communication a non feasible solution, thus wireless transmission becomes necessary. However this demands a huge portion of radio spectrum. In this work, we aim to provide the secure and reliable SG communication...
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