arXiv subjects

Andrea M. Tonello

Publications and source records attributed to Andrea M. Tonello.

At least 37 records · Page 2Linked to original sources

arXiv2019

Machine Learning Tips and Tricks for Power Line Communications

A great deal of attention has been recently given to Machine Learning (ML) techniques in many different application fields. This paper provides a vision of what ML can do in Power Line Communications (PLC). We firstly and briefly describe classical formulations of ML, and distinguish deterministic from statistical learning models with relevance to communications. We then discuss ML applications in PLC for each layer, namely, for characterization and modeling, for the development of physical layer algorithms, for media access control and networking. Finally, other applications of PLC that can benefit from the usage of ML, as grid diagnostics, are analyzed. Illustrative numerical examples are reported to serve the purpose of validating the ideas and motivate future research endeavors in this stimulating signal/data processing field.

eess.SP↗

arXiv2019

Smart Grid Monitoring Using Power Line Modems: Anomaly Detection and Localization

The main subject of this paper is the sensing of network anomalies that span from harmless impedance changes at some network termination to more or less pronounced electrical faults, considering also cable degradation over time. In this paper, we present how to harvest information about such anomalies in distribution grids using high frequency signals spanning from few kHz to several MHz. Given the wide bandwidth considered, we rely on power line modems as network sensors. We firstly discuss the front-end architectures needed to perform the measurement and then introduce two algorithms to detect, classify and locate the different kinds of network anomalies listed above. Simulation results are finally presented. They validate the concept of sensing in smart grids using power line modems and show the efficiency of the proposed algorithms.

eess.SP↗

arXiv2019

Smart Grid Monitoring Using Power Line Modems: Effect of Anomalies on Signal Propagation

The aim of the present work is to provide the theoretical fundamentals needed to monitor power grids using high frequency sensors. In our context, network monitoring refers to the harvesting of different kinds of information: topology of the grid, load changes, presence of faults and cable degradation. We rely on transmission line theory to carry out a thorough analysis of how high frequency signals, such those produced by power line modems, propagate through multi-conductor power networks. We also consider the presence of electrical anomalies on the network and analyze how they affect the signal propagation. In this context, we propose two models that rely on reflectometric and end-to-end measurements to extrapolate information about possible anomalies. A thorough discussion is carried out to explain the properties of each model and measurement method, in order to enable the development of appropriate anomaly detection and location algorithms.

eess.SP↗

arXiv2018

New Findings about Multi Conductor Noise in Narrow Band PLC

The market projection for Internet of Things (IoT) systems is appealing for the Power Line Communication (PLC) technology. A massive growth and a pervasive presence of these IoT objects is expected in our everyday life. About 20 billion of IoT devices are forecasted to be installed in the next two years. PLC is a compelling technology that could become essential for certain IoT applications. For example, sensor nodes and actuators used in the Smart Buildings domain can be connected through PLC. In this case, the PLC network will work as a backbone for the in-building communication. PLC systems, in this domain, will help to solve or reduce the overcrowded-spectrum problem, exploiting the existing cable infrastructure. Narrow band (NB) PLC is probably the most suitable type of PLC technology for IoT applications. The main reasons are: simple hardware, good coverage, appropriate bit-rate and low cost. Nevertheless, to guarantee reliable connectivity further analysis and improvements should be done. There are such as signal propagation discontinuities, high channel attenuation and noise. Despite the fact that PLC noise is a well-known problem, it still poses several challenges for this technology. This paper aims at adding some new consideration on this topic. This paper describes new results on MC NB noise. The MC noise is measured between the Live-Protective Earth (L-PE) and between Neutral-Protective Earth (N-PE) pairs (L-PE-N configuration), to exploit the symmetries of the channel. The analysis in this paper considers the whole PLC NB frequency spectrum that ranges from 3 kHz to 500 kHz. It considers the noise observed at the two output ports of a given outlet in an in-building network with three conductors.

cs.IT↗

arXiv2018

Physical Layer Key Generation for Secure Power Line Communications

Leakage of information in power line communication networks is a threat to privacy and security both in smart grids and in-home applications. A way to enhance security is to encode the transmitted information with a secret key. Relying on the channel properties, it is possible to generate a common key at the two communication ends without transmitting it through the broadcast channel. Since the key is generated locally, it is intrinsically secure from a possible eavesdropper. Most of the existing physical layer key generation techniques have been developed for symmetric channels. However, the power line channel is in general not symmetric, but just reciprocal. Therefore, in this paper, we propose two novel methods that exploit the reciprocity of the power line channel to generate common information at the two intended users. This information is processed through different quantization techniques to generate secret keys. To assess the security of the generated keys, we analyze the spatial correlation of the power line channels and verify the low correlation of the possible eavesdropping channels. The two proposed methods are tested on a measurement dataset. The results show that the information leaked to possible eavesdroppers has very low correlation to any secret key.

cs.CR↗

arXiv2018

Broadband MIMO Couplers Characterization and Comparison

This paper focuses on MIMO Power Line Communication (PLC) to provide increased performance. In MIMO PLC, appropriate coupling methods are necessary in order to enable the effective injection of the signal through the broad band PLC channel so that high data rates can be achieved. In this paper, we want to analytically characterize strengths and weaknesses of each coupler design (topology) from an electrical circuit perspective. We dwell on the description and analysis of the three main and common configurations used for the MIMO couplers: star (S), triangle ($Δ$) and T.

eess.SP↗

arXiv2018

Smart Routing for Improved PLC Backhauling of the Radio Access Network

Transmission line theory enables the bottom up study of networks based on wireline infrastructures. This technique is here applied to a simulator that brings together powerline communication networks with small radio cells ones in a hybrid paradigm: this allows to implement a study of channel capacity and communication quality based on the geometrical properties of the network and the type of cables employed to enable connectivity. Results are shown regarding how deterministic properties related to performance in the network can be retrieved and used to enable a smart routing algorithm.

cs.NI↗

arXiv2017

Modeling Transmission and Radiation Effects when Exploiting Power Line Networks for Communication

Power distribution grids are exploited by Power Line Communication (PLC) technology to convey high frequency data signals. The natural conformation of such power line networks causes a relevant part of the high frequency signals traveling through them to be radiated instead of being conducted. This causes not only electromagnetic interference (EMI) with devices positioned next to power line cables, but also a consistent deterioration of the signal integrity. Since existing PLC channel models do not take into account losses due to radiation phenomena, this paper responds to the need of developing accurate network simulators. A thorough analysis is herein presented about the conducted and radiated effects on the signal integrity, digging into differential mode to common mode signal conversion due to network imbalances. The outcome of this work allows each network element to be described by a mixed-mode transmission matrix. Furthermore, the classical per-unit-length equivalent circuit of transmission lines is extended to incorporate radiation resistances. The results of this paper lay the foundations for future developments of comprehensive power line network models that incorporate conducted and radiated phenomena.

physics.soc-ph↗

arXiv2017

Analysis of High Frequency Impedance Measurement Techniques for Power Line Network Sensing

A major aspect in power line distribution networks is the constant monitoring of the network properties. With the advent of the smart grid concept, distributed monitoring has started complementing the information of the central stations. In this context, power line communications modems deployed throughout the network provide a tool to monitor high frequency components of the signals traveling through a power line network. We propose therefore to use them not only as communication devices but also as network sensors. Besides classical voltage measurements, these sensors can be designed to monitor high frequency impedances, which provide useful information about the power line network, as for instance status of the topology, cable degradation and occurrence of faults. In this article, we provide a technical analysis of different voltage and impedance measurement techniques that can be integrated into power line modems. We assess the accuracy of the techniques under analysis in the presence of network noise and we discuss the statistical characteristics of the measurement noise. We finally compare the performances of the examined techniques when applied to the fault detection problem in distribution networks, in order to establish which technique gives more accurate results.

physics.soc-ph↗

arXiv2017

A Synthetic Statistical MIMO PLC Channel Model Applied to an In-Home Scenario

This paper proposes a synthetic statistical top-down MIMO power line communications channel model based on a pure phenomenological approach. The basic idea consists of directly synthesizing the experimental channel statistical properties to obtain an extremely compact model that requires a small set of parameters. The model is derived from the analysis of the in-home 2 $\times$ 3 MIMO PLC channel data set obtained by the ETSI Specialist Task Force 410 measurement campaign in the band 1.8-100 MHz. The challenge of modeling the channel statistical correlation, exhibited among the frequencies and between the MIMO modes, in compact form is tackled and it is shown that a small set of parameters can be used to reconstruct such a correlation behavior. The model is validated and compared to the measured channels, showing a good agreement in terms of average channel gain, root-mean-square delay spread, coherence bandwidth, and channel capacity distribution.

cs.IT↗

arXiv2016

EMC Regulations and Spectral Constraints for Multicarrier Modulation in PLC

This paper considers Electromagnetic Compatibility (EMC) aspects in the context of Power Line Communication (PLC) systems. It offers a complete overview of both narrow band PLC and broad band PLC EMC norms. How to interpret and translate such norms and measurement procedures into typical constraints used by designers of communication systems, is discussed. In particular, the constraints to the modulated signal spectrum are considered and the ability of pulse shaped OFDM (PS-OFDM), used in most of the PLC standards as IEEE P1901 and P1901.2, to fulfill them is analyzed. In addition, aiming to improve the spectrum management ability, a novel scheme named Pulse Shaped Cyclic Block Filtered Multitone modulation (PS-CB-FMT) is introduced and compared to PS-OFDM. It is shown that, PS-CB-FMT offers better ability to fulfill the norms which translates in higher system capacity.

cs.IT↗

arXiv2016

Novel Grid Topology Estimation Technique Exploiting PLC Modems

A fundamental requirement to develop routing strategies in power line networks is the knowledge of the network topology, which might not be complete. In this work, we present a novel method to derive the topology of a distribution network that exploits the capability of Power Line Communication modems to measure the network admittance, and we report the most significant results.

cs.OH↗

arXiv2016

Statistical Assessment of PLC Networking for Front-Hauling in Small Radio Cells

The employment of power lines for communications (PLC) has been theorized almost a century ago; although the physical medium is not meant for data transmission, recent technical developments pushed the capacity boundary much higher than expected, allowing to consider PLC for new applications as the one considered in this contribution, i.e., as a solution for small cell back/front-hauling. In principle, back-hauling for cellular networks via PLC is very attractive given how pervasive the power line infrastructure is. Telecom operators are looking for solutions that can handle the traffic increase which is doublying every year. This calls for improvements of both cellular systems and front-hauling technologies that have to bridge the radio network with the core network. Small cells are currently advocated as the solution to spatially fragment the network and offer high capacity in densely populated areas; this is also due to the availability of spectrum at high frequency (mmWave links) which inherently offers large bandwidth but forces the cells to become smaller due to the short distance coverage. Therefore, it appears that mobile operators may eventually have to deploy an order of magnitude more (small) cells compared to existing networks having macro cells. This translates in a high density cellular network that poses more challenges for the back-haul.

cs.NI↗

arXiv2016

On the Exploitation of Admittance Measurements for Wired Network Topology Derivation

The knowledge of the topology of a wired network is often of fundamental importance. For instance, in the context of Power Line Communications (PLC) networks it is helpful to implement data routing strategies, while in power distribution networks and Smart Micro Grids (SMG) it is required for grid monitoring and for power flow management. In this paper, we use the transmission line theory to shed new light and to show how the topological properties of a wired network can be found exploiting admittance measurements at the nodes. An analytic proof is reported to show that the derivation of the topology can be done in complex networks under certain assumptions. We also analyze the effect of the network background noise on admittance measurements. In this respect, we propose a topology derivation algorithm that works in the presence of noise. We finally analyze the performance of the algorithm using values that are typical of power line distribution networks.

cs.NI↗

arXiv2016

Orthogonal Design of Cyclic Block Filtered Multitone Modulation

The orthogonal design of a Cyclic Block Filtered Multititone Modulation (CB-FMT) system is addressed. CB-FMT is a filter bank modulation scheme that uses frequency confined prototype pulses, similarly to Filtered Multitone Modulation (FMT). Differently from FMT, where the linear convolution is used, the cyclic convolution is exploited in CB-FMT. This allows to efficiently implement the system via a concatenation of discrete Fourier transforms (DFT). The necessary and sufficient orthogonality conditions are derived in time domain and frequency domain. Then, these conditions are expressed in matrix form and the prototype pulse coefficients are parameterized with hyper-spherical coordinates. The effect of a linear time-variant transmission medium is discussed. In such a scenario, the optimal filter bank orthogonal design is considered with the objective of maximizing either the in-band-to-out-band sub-channel energy ratio or the achievable rate. Numerical results and comparisons show the performance improvements attainable with several designed optimal pulses also w.r.t. the use of the baseline root-raised-cosine pulse.

cs.IT↗

arXiv2016

A Synthetic MIMO PLC Channel Model

The huge and increasing demand of data connectivity motivates the development of new and effective power line communication (PLC) channel models, which are able to faithfully describe a real communication scenario. This is of fundamental importance since a good model represents a quick evaluation tool for new standards or devices, allowing a considerable saving in time and costs. The aim of this paper is to discuss a novel top-down MIMO PLC synthetic channel model, able to numerically emulate a real PLC environment. First, the most common channel modeling strategies are briefly described, highlighting strengths and weaknesses. Afterwards, the basic model approach is described considering the SISO scenario. The implementation strategy is then extended to the MIMO case. The validity of the proposed model is proved making a comparison between the simulated channels and channels obtained with measurements in terms of both performance and statistical metrics. The focus is on the broadband frequency spectrum.

cs.IT↗

arXiv2016

In-Vehicle PLC: In-Car and In-Ship Channel Characterization

This paper deals with power line communication (PLC) in the context of in-vehicle data networks. This technology can provide high-speed data connectivity via the exploitation of the existing power network, with clear potential benefits in terms of cost and weight reduction. The focus is on two scenarios: an electric car and a cruise ship. An overview of the wiring infrastructure and the network topology in these two scenarios is provided. The main findings reported in the literature related to the channel characteristics are reported. Noise is also assessed with emphasis to the electric car context. Then, new results from the statistical analysis of measurements made in a compact electric car and in a large cruise ship are shown. The channel characteristics are analysed in terms of average channel gain, delay spread, coherence bandwidth and achievable transmission rate. Finally, an overall comparison is made, highlighting similarities and differences taking into account also the conventional (combustion engine) car and the largely investigated in-home scenario.

cs.OH↗

arXiv2016

State-of-the-art in Power Line Communications: from the Applications to the Medium

In recent decades, power line communication has attracted considerable attention from the research community and industry, as well as from regulatory and standardization bodies. In this article we provide an overview of both narrowband and broadband systems, covering potential applications, regulatory and standardization efforts and recent research advancements in channel characterization, physical layer performance, medium access and higher layer specifications and evaluations. We also identify areas of current and further study that will enable the continued success of power line communication technology.

cs.NI↗