Performance evaluation of networking protocols for connected vehicles

Modern cars feature many embedded systems that monitor and manage all the critical sensors and actuators. The interconnection of such systems is a challenging task since the information to be exchanged is of mission-critical nature and affects the driving experience. The vehicle connectivity can be further extended with Vehicle-to-Vehicle (V2V) technology, which allows cars to exchange sensory information and even act on it. In this article a unified networking architecture is presented, starting from the inside of the vehicle and the interconnection of various control units and ultimately targeting Car-to-Car communications which enable smarter, safer and more efficient transportation. The researchers review and evaluate the performance of Power Line Communications as a solution for in-car networking. Then the safety-critical data as well as multimedia originating from each individual vehicle's in-car network are broadcasted to other neighbouring vehicles via IEEE 802.11p in a simulation environment featuring realistic vehicular mobility

Worst-case access delay of HomePlug Green PHY (HPGP) for delay-critical in-vehicle applications

The increasing complexity of automotive electronics has put considerable pressure on automotive communication networking to accommodate in-vehicle information flows. The use of power lines has been a promising alternative to in-vehicle communications because of elimination of extra data cables. In this paper, we focus on the latest HomePlug Green PHY (HPGP) which has been promoted by major automotive manufacturers for green communications with electric vehicles, and study its worst-case access delay performance in supporting delaycritical in-vehicle applications using both theoretical analysis and the simulation. Specifically, we apply Network Calculus as a deterministic modeling approach to evaluate the worst delay and further verify its performance using the OMNeT++ simulation. Evaluation results are also supplemented to compare with legacy methods and provide useful guidelines for developing HPGP based vehicular power line communication systems

Delay analysis and time-critical protocol design for in-vehicle power line communication systems

With the emerging automated tasks in vehicle domain, the development of in-vehicle communications is increasingly important and subjected to new applications. The use of vehicular power lines has been a promising alternative to invehicle communications because of elimination of extra data cables. In this paper, we focus on the latest HomePlug Green PHY (HPGP) and explore its opportunity to support timecritical in-vehicle applications. Specifically, we apply Network Calculus to evaluate the worst access and queuing delay of various priority flows in vehicle bus networks. In order to maximize the bandwidth utility and satisfy the end-to-end hard delay requirements, we further propose a bandwidth efficient fair rate scheduling and delay sensitive traffic shaper. Performance evaluation supplemented by numerical and simulation results is also provided to show the advantage of HPGP and the proposed traffic shaper over the existing industry solutions

Powerline communication and demand side management for microgrids

Motivation: The greatest challenge for microgrid deployment is making energy affordable, especially in remote low-income communities. This thesis answers the following research question: Can digital communication reduce the price of electricity for an islanded low voltage microgrid and if so, can broadband powerline communications meet microgrid control requirements? Approach: This study conducts a cost-benefit analysis of the addition of a field area network to a microgrid. Broadband powerline communication is selected as a candidate technology and tested on various microgrid networks to determine its suitability. Results: The main contributions of this study are: A demand-side management strategy and unsubsidised cost reflective tariff structure for rural microgrids in the developing world. A cost-benefit analysis that shows the addition of a low bit rate, medium latency communication system (1 kbps per customer, 100 ms) may reduce the levelized cost of energy by 32%. A performance evaluation of broadband HomePlug powerline communications for microgrids which shows the Homeplug AV2 has a range of 600 m and functions well on complex radial distribution networks. Conclusion: Investment in a minimally capable communication system has significant economic benefit to both customer and utility by enabling smart grid services such as automatic meter reading and demand side management. Since communication technologies share similar bit rate and latency capabilities and are similarly priced, the technology choice is driven more by microgrid geography, complexity, availability and reliability. Powerline communications require no additional cable, but boast reliability similar to dedicated cable solutions. The HomePlug AV meets bit rate and latency requirements, is affordable, reliable, simple and widely available around the world. This study concludes it is a solid candidate for low voltage islanded microgrids. The material presented in this thesis has been published or submitted for publication in an abbreviated format in the following publications: D. Neal et al, "Demand side energy management and customer behavioral response in a rural islanded microgrid," in IEEE PES/IAS PowerAfrica, 2020. D. Neal, D. Rogers and M. McCulloch, "A Techno-Economic Analysis of Communication in Islanded Microgrids," unpublished. Submitted Oct 2023 to Elsevier Renewable and Sustainable Energy Reviews. D. Neal, D. Rogers and M. McCulloch, "Broadband Powerline Communication for Low-Voltage Microgrids," unpublished. Submitted Oct 2023 to IEEE Transactions on Power Delivery

Sincronizzazione tra dispositivi su Power Line Communications per Smart Grid

Lo scopo di questa tesi è quello di fornire una panoramica sull'ambiente delle Smart Grid, sull'evoluzione della rete elettrica esistente e sui miglioramenti portati da questa tecnologia. Verrà fatta una presentazione anche delle Power Line Communications (PLC), una tecnologia di comunicazione che si propone come struttura di comunicazione per la Smart Grid, analizzandone anche l'articolato modello di canale. Verranno presi in considerazione vari protocolli di PLC, applicabili ad un ambiente smart grid, con particolare interesse verso PRIME, il protocollo che sarà poi implementato nel progetto di tesi. L'obiettivo del progetto consiste nel gestire la sincronizzazione tra due dispositivi PLC forniti da Texas Instruments attraverso un Development Kit, riferendosi alla tecnologia Smart Grid e al protocollo PRIME. Sarà quindi sviluppato un algoritmo che corregge il clock di un nodo Slave, sincronizzandolo al nodo Master. Per fare questo verranno illustrate le varie tecniche adottate nel procedimento, dalla stima del Round Trip Time, al calcolo e correzione dell'offset di tempo fino al calcolo e correzione dell'offset di frequenza, e infine verranno illustrati i risultati raggiunti dall'algoritm

The role of communication systems in smart grids: Architectures, technical solutions and research challenges

The purpose of this survey is to present a critical overview of smart grid concepts, with a special focus on the role that communication, networking and middleware technologies will have in the transformation of existing electric power systems into smart grids. First of all we elaborate on the key technological, economical and societal drivers for the development of smart grids. By adopting a data-centric perspective we present a conceptual model of communication systems for smart grids, and we identify functional components, technologies, network topologies and communication services that are needed to support smart grid communications. Then, we introduce the fundamental research challenges in this field including communication reliability and timeliness, QoS support, data management services, and autonomic behaviors. Finally, we discuss the main solutions proposed in the literature for each of them, and we identify possible future research directions

Transmission of compressed images over power line channel

In the telecommunications industry, the use of existing power lines has drawn the attention of many researchers in the recent years. PLC suffers from impulsive noise that can affect data transmission by causing bit or burst errors. In this thesis, PLC channel was used as a transmission scheme to transmit compressed still images using FFT-OFDM. When lossy compression is applied to an image, a small loss of quality in the compressed image is tolerated. One of the challenging tasks in image compression and transmission is the trade-off between compression ratio and image quality. Therefore, we utilized the latest developments in quality assessment techniques, SSIM, to adaptively optimize this trade-off to the type of image application which the compression is being used for. A comparison between different compression techniques, namely, discrete cosine transform (DCT), discrete wavelet transform (DWT), and block truncation coding (BTC) was carried out. The performance criteria for our compression methods include the compression ratio, relative root-meansquared (RMS) error of the received data, and image quality evaluation via structural similarity index (SSIM). Every link in a powerline has its own attenuation profile depending on the length, layout, and cable types. Also, the influences of multipath fading due to reflections at branching point vary the attenuation profile of the link. As a result, we observed the effect of different parameters of the PLC channel based on the number of paths, and length of link on the quality of the image. Simulations showed that the image quality is highly affected by the interaction of the distance of PLC channel link and the number of multipath reflections. The PLC channel is assumed to be subjected to Gaussian and impulsive noises. There are two types of impulsive noise: asynchronous impulsive noise and periodic impulsive noise synchronous to the mains frequency. BER analysis was performed to compare the performance of the channel for the two types of impulsive noise under three impulsive scenarios. The first scenario is named as "heavily disturbed" and it was measured during the evening hours in a transformer substation in an industrial area. The second scenario is named as "moderately disturbed" and was recorded in a transformer substation in a residential area with detached and terraced houses. The third scenario is named as "weakly disturbed" and was recorded during night-time in an apartment located in a large building. The experiments conducted showed that both types of noise performed similarly in the three impulsive noise scenarios. We implemented Bose-Chaudhuri-Hocquenghen (BCH) coding to study the performance of Power Line Channel (PLC) impaired by impulsive noise and AWGN. BCH codes and RS codes are related and their decoding algorithms are quite similar. A comparison was made between un-coded system and BCH coding system. The performance of the system is assessed by the quality of the image for different sizes of BCH encoder, in three different impulsive environments. Simulation results showed that with BCH coding, the performance of the PLC system has improved dramatically in all three impulsive scenarios

A taxonomy of cyber-physical threats and impact in the smart home

In the past, home automation was a small market for technology enthusiasts. Interconnectivity between devices was down to the owner’s technical skills and creativity, while security was non-existent or primitive, because cyber threats were also largely non-existent or primitive. This is not the case any more. The adoption of Internet of Things technologies, cloud computing, artificial intelligence and an increasingly wide range of sensing and actuation capabilities has led to smart homes that are more practical, but also genuinely attractive targets for cyber attacks. Here, we classify applicable cyber threats according to a novel taxonomy, focusing not only on the attack vectors that can be used, but also the potential impact on the systems and ultimately on the occupants and their domestic life. Utilising the taxonomy, we classify twenty five different smart home attacks, providing further examples of legitimate, yet vulnerable smart home configurations which can lead to second-order attack vectors. We then review existing smart home defence mechanisms and discuss open research problems