Alberto Pittolo

In-Home Power Line Communication Channel: Statistical Characterization

A statistical characterization of the in-home power line communication channel is performed from the study of a wide set of measured channels in the 1.8-100 MHz frequency band. The study provides new insights on (a) the relation between the line impedance and the channel frequency response (CFR), and (b) on the spatial relation between the channels that share either the transmitter or the receiver outlet. Furthermore, it confirms the validity of some results presented in the literature that are limited to the 30 MHz band. The study comprises the analysis of the average channel gain, the root-mean-square delay spread and the coherence bandwidth, as well as the relation between such quantities and the phase of the CFR. Closed-form expressions are provided to model the quantities and their relations. Finally, the coverage, i.e., the relation between the maximum achievable rate and the distance, as well as the achievable rate gain offered by the use of the frequency band up to 300 MHz, are studied.

State of the Art in Power Line Communications: From the Applications to the Medium

In recent decades, power line communication (PLC) has attracted considerable attention from the research community and industry, as well as from regulatory and standardization bodies. In this paper, 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 the areas of current and further study that will enable the continued success of PLC technology.

Physical layer security in power line communication networks: an emerging scenario, other than wireless

The authors consider the secure transmission of information over power line communication (PLC) networks. The focus is on the secrecy guaranteed at the physical layer, named physical layer security (PLS). Although PLS has been deeply investigated for the wireless case, it is not the same for the PLC environment. Thus, starting from the knowledge in the wireless context, the authors extend the results to typical PLC scenarios. In particular, the PLC channel statistics is evaluated and a performance comparison among PLC and wireless channels is performed, in terms of secrecy rate distribution. For the PLC case, the secrecy rate distribution, under a total power constraint, is evaluated for both optimal and uniform power distributions in broadband channels. To provide experimental evidence, the authors consider channel measures obtained in an in-home measurement campaign. The underlying network presents a tree topology, which introduces frequency and spatial correlation among channels, and suffers from the keyhole effect, generated by branches that depart from the same node. As shown by the numerical results, these effects can reduce the secrecy rate. Finally, the authors evaluate the secrecy rate region for the multi-user broadcast channel considering both simulated channel realisations and experimental channel measures.

In-Vehicle Power Line Communication: Differences and Similarities Among the In-Car and the In-Ship Scenarios

This article deals with power line communication (PLC) in the context of invehicle 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 (EC) 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 on the EC context. New results from the statistical analysis of measurements made in a compact EC and in a large cruise ship are also shown. The channel characteristics are analyzed in terms of average channel gain (ACG), delay spread (DS), coherence bandwidth (CB), and achievable transmission rate. Finally, an overall comparison is made, highlighting similarities and differences while taking into account the conventional combustion engine car and the largely investigated in-home scenario.

Physical layer security in PLC networks: Achievable secrecy rate and channel effects

We consider confidential data communication over power line communication (PLC) networks. In particular, rather than analyzing cryptographic techniques, we focus on the security provided at the physical layer, named physical layer security (PLS). Although physical layer security is widely discussed for wireless systems, we can not say the same for the PLC context. As a starting point, the wireless case will be examined. Then, we highlight the differences with PLC and we compare the average secrecy rate that can be achieved in typical wireless and PLC fading channels. Both optimal and uniform power distributions are considered. The theoretical results show that wireless fading channels provide higher secrecy rate than PLC channels. This is due to different channel statistics and propagation scenario. To provide experimental evidence, we consider channel measures obtained in a in-ship and in a in-home measurement campaign. While log-normal fading fits well the former channels, the latter channels are not strictly log-normal. Furthermore, the considered in-home network topology introduces correlation among channels, and it is subject to the keyhole effect introduced by branches that depart from the same node. These effects can reduce the secrecy rate.

Considerations on narrowband and broadband power line communication for smart grids

The high amount of applications to be implemented in the Smart Grid requires bi-directional connectivity between a multitude of nodes with a reliable, high speed, low latency, energy efficient and cost effective communication technology. Power line communication (PLC) has the potentiality to meet the requirements. Indeed, there exists space for PLC technology improvements and to overcome the challenges mostly due to a hostile communication medium. There are two considered frequency spectra: a narrowband (3-500 kHz) spectrum and a broad band (1.8-86 MHz) spectrum that are exploited by current technology. In this paper, we discuss the usage of these spectra both in LV and MV networks, highlighting pros and cons and advocating the realization of an adaptive technology that can cognitively make the best usage of available resources so that the requirements of reliability, latency and coverage can be met.

Performance of MIMO PLC in measured channels affected by correlated noise

We study the performance improvement provided by the use of precoding schemes in multiple-input multiple-output (MIMO) power line communications (PLC) in the presence of additive colored and correlated Gaussian noise. We assume a power spectral density constraint, according to the HomePlug AV2 standard, and we focus on a 2 × 4 MIMO system, thus exploiting also the common mode at the receiver side. The MIMO channels have been obtained through an experimental measurement campaign across Europe, collected by the ETSI special task force 410. We compare the performance (in terms of capacity) when the power allocation is optimal or uniform. Furthermore, a comparison with the single-input single-output (SISO) and reduced-dimension MIMO configurations is made, showing as the 2 × 4 MIMO scheme outperforms the others.

Physical Layer Security in Power Line Communication Networks

This chapter digs into the secrecy provided and guaranteed at the physical layer, named physical layer security (PLS), over power line communication (PLC) channels for in-home networks. The PLC scenario peculiarities are briefly discussed in terms of channel characteristics and noise features. The effects of the channel properties on the performance are evaluated, in terms of the achievable secrecy rate, starting from the single-input single-output (SISO) scheme with additive white Gaussian noise. The results are also compared to the more common wireless scenario, namely a scenario where the channels are independent and experience Rayleigh fading as a consequence of rich scattering. Furthermore, the performance improvement attainable with the use of multiple-input multiple-output (MIMO) transmission is discussed. The effect of increasing the transmission band 2–30 to 2–86 MHz and the effect of colored spatially correlated noise is also investigated. Moreover, a non uniform power allocation strategy, provided by the application of an alternating optimization (AO) approach is evaluated. A comparison with the channel capacity, achieved without secrecy constraints, is also performed. The experimental results are provided relying on measured noise and channel responses.

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

Power Line Communications: Understanding the Channel for Physical Layer Evolution Based on Filter Bank Modulation

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