Aiming to illuminate the path towards integrating energy harvesting (EH) technologies into modern electric power systems, thereby enabling more efficient and sustainable energy solutions, this paper explores energy harvesting within electric power systems and points out its potential to power data communication purposes. In this sense, we examine the overarching principles of EH in these systems, spotlighting both the merits and limitations associated with energy extraction across varying voltage levels and electric signal frequency bands. Central components of EH devices, alongside a spectrum of harvesting methodologies, are thoroughly reviewed. Also, we showcase a case study that provides a quantitative assessment of EH potential in electric power systems. The manuscript culminates in a forward-looking analysis of EH, considering emerging technologies that promise to redefine the landscape. These include integrating hybrid power line and wireless systems, strategies for optimal power allocation, enhancements in physical layer security, the innovative concept of negawatts, advancements in harvesting circuit designs and applying non-orthogonal multiple access techniques

The purpose of this paper is twofold. The first is to show how to deploy routing protocols in the FABRIC national-scale testbed, presenting examples step-by-step from the perspective of a network researcher who needs to book a slice composed of a topology with multiple paths, diversity of links, nodes with specific network interfaces (shared or/and programmable NICs) that form the basis to build a real-world network experiment. The second is to use the available tools (“metaresearch” API) to demonstrate how reproducible is the experimentation process, taking the evaluation of OSPF failure recovery and traffic throughput over dedicated smartNICS as use cases.

Este artigo propõe um ambiente virtual de experimentação de mecanismos de Engenharia de Tráfego para aplicações de Ciência de Dados Intensiva baseado na plataforma RARE/freeRtr, permitindo que experimentos complexos possam ser testados antes de serem transferidos para um testbed físico com switches programáveis P4. O estudo define os requisitos das redes para Ciência de Dados Intensiva e demonstra como esses requisitos podem ser atendidos pelo protocolo de Roteamento de Fonte PolKA, habilitando migração ágil de rotas, tolerância à falhas e balanceamento de carga baseado em políticas.

Transmission medium is always perturbed by noise with a random nature which can be characterized by taking a sequence of noise samples and, after analyzing the sequence, attributing a probabilistic model to represent the randomness of the noise. If thermal noise (receiver generated) is the only noise impairing the transmission (our only focus is digital transmission) the memoryless stationary discrete-time Gaussian process is the best model to probabilistically represent the noise. The mathematical representation of the transmission medium in such a situation yields the well known Gaussian Channel. As Information Theory points out, for a fixed noise power, the Gaussian channel is the worst channel to send information through. If thermal noise is not the only noise impairing the transmission (as in sonar communication and power line communication) finding the probabilistic model other than the single-parameter Gaussian process, which best match the noise can much improve the communication system design. The Bernoulli-Gaussian process, a three parameters model, is a common considered option. Finding the three parameters of the Bernoulli-Gaussian model (from known noise samples) is a formidable task that can be made simpler by considering the (original) results presented in the current paper. The Bernoulli-Gaussian model can be characterized, analytically, by using the noise power and two additional quantities: the expectation of the absolute value of the noise process plus the expected value of the third power of the absolute value. In practice the parameters would be calculated using estimates of the mentioned expected values. The communication system design can be much improved if a well fit Bernoulli-Gaussian stochastic process is selected to model the noise. This is an alternative to model the communication using power lines which is often modeled as Middleton Class-A. The rate harvested when modeling the medium as a Bernoulli-Gaussian channel, it is shown, is increased when compared to modeling the medium with the easily obtained Gaussian channel.

This paper investigates power allocation for minimizing the average bit error probability (BEP) in hybrid communication systems, more specifically hybrid power line/wireless systems (HPWSs). In this regard, a brief discussion of HPWSs is presented in order to point out the complementary characteristics of power line and wireless media. By considering orthogonal frequency-division multiplexing and maximal-ratio combining, optimization problems associated with the minimization of the average BEP in hybrid communication systems are formulated under two distinct transmission power constraints, called sum power and sum power-channel constraints. For both constraints, it is demonstrated that at most one medium should be used for data transmission over subchannels with the same index in order to minimize the average BEP in hybrid communication systems. Based on this finding, power allocation algorithms are derived for this purpose in HPWSs. Numerical analyses are then used to validate the proposed algorithms by comparing them with interior-point-based power allocation algorithms. In addition, performance comparisons show the advantage of the proposals over alternative algorithms from the literature, including previous algorithms proposed for maximizing the achievable data rate.

This work discusses the block error probability of an uncoded and single-carrier data communication system when short and finite-length blocks of symbols are transmitted and both the average energy and the additive noise variance need to be estimated at the receiver side. The lack of relevant information introduces more uncertainty at the receiver side, and a stochastic formulation needs to be adopted in order to characterize such randomness based on the availability of a short-length block of received symbols. Closed-form expressions for the probabilistic model are presented for both M-PAM and M-QAM constellations and flat fading channel. Finally, numerical results show that, to ensure a target block error probability, a trade-off between block length and a proposed uncertainty factor must be carefully considered for performing data communication under such constraint.

This letter proposes a joint channel estimation and Schmidl & Cox synchronization for the orthogonal chirp-division multiplexing (OCDM) scheme. First, it is proven that a symbol composed of two identical halves in the Fresnel domain has two identical halves in the time domain, which is required by the considered synchronization technique. In sequel, a Fresnel-domain pilot symbol that enables joint channel estimation and synchronization is proposed, allowing overhead reduction and hence higher data rates. Finally, measurement and simulation results validate the obtained findings for both passband and baseband OCDM schemes.

This paper introduces an analytical framework for analyzing the benefits of using the waste-to-energy concept to improve power quality and energy efficiency in electric power systems. In this framework, closed-form expressions for evaluating the analytic cross-power spectral density between voltage and current signals are introduced to quantify the wasted energy associated with undesirable components of electric signals that result from the interaction between nonlinear loads and electric power systems. These expressions demonstrate the existing relationship between the analytic cross-power spectral density and the well-known complex power, which is widely used in electric power systems. In the sequel, it is shown that these expressions allow the introduction of the so-called Passive Filtering Energy Recovery, which aims to recover the wasted energy from the undesirable components of electric signals. Numerical results show that the Passive Filtering Energy Recovery, which relies on the waste-to-energy concept, can improve power quality and energy efficiency in the Brazilian and worldwide electric power systems.

This paper focuses on a comprehensive analysis of typical power line communication (PLC) pulses for sensing high impedance faults in power distribution networks (PDNs) when the pulse compression time-domain reflectometry (TDR) system applies. In this sense, closed-form expressions for the PLC pulses, namely Hermitian symmetric orthogonal frequency-division multiplexing (HS-OFDM), impulsive ultra-wideband (UWB), and chirp spread spectrum (CSS), and their corresponding autocorrelation functions are presented. Also, parameters based on radar theory (e.g., range resolution, pulse compression ratio, reflectogram distortion, and maximum unambiguous range) are introduced to evaluate the usefulness of these PLC pulses for providing proper TDR measurements (reflectograms). A comparative numerical analysis considering frequency bands that comprise narrowband and broadband PLC systems, with a highlight on well-established regulatory constraints, is discussed. Numerical results show that the use of UWB pulses yields a larger number of reflectograms in a given time interval, while HS-OFDM and CSS pulses provide higher reflectogram quality and better resolution, under the same conditions. Also, narrowband PLC systems are suitable for the majority of PDNs, with the use of broadband PLC ones left for attaining high resolutions at short distances.

This paper investigates the feasibility of a quantum-secure Key Encapsulation Mechanism (KEM) in hardware constrained Smart Meter (SM) equipment. In this sense, the Cryptographic Suite for Algebraic Lattices (CRYSTALS)-Kyber scheme, the new standard for post-quantum Public-Key Encryption (PKE) systems chosen by the post-quantum cryptography (PQC) standardization process, is scrutinized and implemented in a System-on-a-Chip (SoC) Field Programmable Gate Array (FPGA) device. Experimental results show that the proposed hardware/software co-design implementation of the CRYSTALS-Kyber scheme in an SoC FPGA device reduces its execution time by around 70% compared to its software implementation. Moreover, the hardware resource analysis shows that the proposed hardware/software co-design implementation of the CRYSTALS-Kyber scheme in an SoC device is feasible for SM equipment.

Due to high power consumption and other problems, it is unlikely that orthogonal frequency-division multiplexing (OFDM) would be included in the uplink of the future 6G standard. High power consumption in OFDM systems is motivated by the high peak-to-average power ratio (PAPR) introduced by the inverse Fourier transform (IFFT) processing kernel in the time domain. Linear precoding of the symbols in the frequency domain using discrete Hartley transform (DHT) could be used to minimise the PAPR problem, however, at the cost of increased complexity and power consumption. In this study, we minimise the computation complexity of the DHT precoding on OFDM transceiver schemes and the consequent power consumption. We exploit the involutory properties of the processing kernels to process the DHT and IFFT as a single-processing block, thus reducing the system complexity and power consumption. These also enable a novel power-saving receiver design. We compare the results to three other precoding schemes and the standard OFDM scheme as the baseline; while improving the power consumption efficiency of a Class-A power amplifier from 4.16% to 16.56%, the bit error ratio is also enhanced by up to 5 dB when using a 1/2-rate error-correction coding and 7 dB with interleaving.

This paper introduces a hybrid cooperative spectrum sensing technique that exploits the existing diversity between power line and wireless media with the purpose of improving spectrum sensing functionalities in power line communication (PLC) systems, which operate in the frequency band between 1.7 and 100 MHz. To evaluate the performance of the proposed technique, a data set obtained from a measurement campaign is analyzed, and a feature evaluation reveals that the signal energy is the most relevant feature of all extracted ones. Also, the performance evaluation of the proposed technique shows that the exploitation of the existing diversity between signals acquired from both electric power grid and air can remarkably improve the detection of spectrum occupancy or holes in comparison to the sole use of one of them.

This study discusses an augmented investigation of the hybrid wiretap channel, which represents a PLC system with its data security threatened by a malicious and passive wireless device at the physical layer level, by focusing on the evaluation and analysis of wiretap code rates. The wiretap code rates are obtained through effective secrecy throughput. In this sense, numerical analyses based on real data set composed of channel estimates and measured additive noises are provided. This data set was collected from a measurement campaign carried out in several Brazilian houses. From the perspective of the physical layer security, the attained results show wiretap code rates for overcoming the malicious presence of a passive wireless device located in the vicinity of broadband PLC systems under practical scenarios.

—Aiming to bring attention to the necessity of dealing with the dynamics of access impedance in electric power systems, this paper introduces an adaptive impedance matching circuit that is based on an analog filter bank approach. In this sense, it describes a prototype that validates the proposed filter bank approach for improving impedance matching. Numerical results obtained with the detailed prototype operating in the frequency band between 2 and 500 MHz show that the proposed analog filter bank approach helps to improve impedance matching in power line communication (PLC) systems. Also, the numerical results show that the dynamics of impedance matching between two or more PLC transceivers is a difficult task to be accomplished because real-time coordination among them is necessary. Overall, it is shown that the proposed analog filter bank approach constitutes an interesting research direction for improving impedance matching between PLC transceivers and electric power systems.

Aiming to improve energy reliability in base stations (on- and off-grid), this paper focuses on the benefits of a feasible solution that applies a multiple-output singleton type-1 Mamdani fuzzy system to monitor and manage existing energy sources. It also shows how useful the reliability function is for quantifying energy reliability in base stations under the stochastic availability of the existing sources of energy. In this sense, it pays attention to a macro base station that can be feed by a power utility, wind source, solar source, and diesel generator. Numerical results show that using the chosen fuzzy system results in a simple and effective technique for switching among the available sources of energy.

Aiming to come up with strategies for harvesting energy in hybrid power line communication (PLC)-wireless systems, this work focuses on the amount of energy that can be potentially harvested from the additive noise in electric power grids and in the air within residential facilities when the frequencies from 1.7 up to 100~MHz are taken into account. Based on statistical analyses of a residential data set, we show that the average power of the measured additive noise in the power line is higher in the morning than other periods of the day. Also, it is higher than the values from the energy harvested from in the air, in the same frequency band. Moreover, we show that the amount of energy harvested from these additive noises can yields achievable data rates between hundreds of kbps up to dozens of Mbps if hybrid PLC-wireless channels are used for data communication purposes.

—This work advances the study of indoor hybrid PLC-wireless channels when the frequency band delimited by 1 . 7 MHz and 100 MHz is taken into account. In this sense, a measurement campaign was carried out in a building facility to investigate the wireless signal propagation of these kind of channels. Based on the collected measures of PLC-wireless channels and additive noises, it is reported a agreement with previous works, in terms of average channel gain, power spectral density of additive noise and achievable data rates. Also, numerical results show that wireless signal propagation part of PLC-wireless channels can offer several hundreds of Mbps if a wireless device is located up to 6 meters from the power lines. Also, they show that PLC-wireless systems can be powerful tools to benefit wireless communication inside an office.

This paper introduces the orthogonal chirp division multiplexing (OCDM) for baseband data communication systems. The OCDM scheme uses the discrete Fresnel transform in an analogous fashion as the orthogonal frequency division multiplexing (OFDM) uses the discrete Fourier transform. In this regard, this paper outlines the design of types of the OCDM schemes that allow data communication using real-valued time-domain signals and, as a consequence, making possible the application of the OCDM scheme in power line communication systems, which is supposed to operate in the baseband. Numerical analyses show that under the hardness of a noisy environment, the OCDM scheme is able to soften the impulsive noise effects better than previous schemes. Also, the OCDM scheme yields better results when the channel length is unknown, in comparison to Hermitian symmetric OFDM and single carrier-cyclic prefix schemes. Finally, the findings related to the OCDM scheme for baseband data communication are similar to those related to the passband one.

This letter considers a wireless power transfer enabled cooperative communication system where the end-users (EUs) make use of WPT to send energy to intermediate RUs to receive information. In traditional cooperative communications systems, service provider provides the energy for cooperation and the networks are optimized from the service providers’ perspectives. In the this system, EUs compensate for the energy requirements of RUs, and EUs should get a fair service back from RUs. To administrate EUs WPT and ensure the fair service policy, this proposes a novel beamforming technique named Pay-As-You-Go beamforming. This adapts data rates proportional to the amount of energy received from each EUs while optimizing the energy per bit cost of the overall system. Then formulated as an non convex optimization problem and solved with the semi-definite programming relaxation techniques.

This paper focuses on the statistical modeling of the magnitudes of frequency responses of Brazilian in-home power line and hybrid power line-wireless in the frequency band from 1.7 up to 100 MHz.'In this regard, a method to obtain statistical models is detailed. The statistical modelings of these channels are based on measured data sets, which were acquired through a measurement campaign carried out in Brazilian residences. Numerical results show that Beta and Log-Normal are the best statistical distributions for modeling magnitudes of the frequency responses of Brazilian in-home power line and hybrid power line-wireless communication channels, respectively. Also, these magnitudes are non-stationary random processes. (C) 2020 Elsevier B.V. All rights reserved.