A PLC/VDSL2 coexistence method based on noise injection on powerline during VDSL2 initialization

PLC (Power Line Communications) and VDSL2 (Very high bit-rate Digital Subscriber Line) allow high bit-rate transmissions, through power line and copper pair respectively, but both technologies use the same frequency band. Consequently, these technologies could have to coexist in a home network inside the customer premises. This paper describes a theoretical analysis of the electromagnetic coupling between PLC and VDSL2 links. The effects of different parameters such as copper pair characteristics distance between the power line and the copper pair are presented.

After more than two decades since intensive research began on power line communications (PLC) technology, this interesting field of telecommunication engineering is still progressing towards maturity. Despite some factors that delay its worldwide acceptance, its implementation is starting to take off. Research in PLC is motivated (i) by many factors such as the crowded radio frequency spectrum that requires to be sustained by alternative technologies and (ii) by the emanation of other new technologies that may help PLC to extend its practical implementation such as visible light communications or other wireless communication technologies like near‐field communications. PLC technology is used in applications requiring both low and high data rate but traditionally exploited in applications in which the node does not move. Nowadays, PLC has become widely accepted; hence, a review of the technology may be useful to keep the readers aware of new updates. In this paper, we provide an overview of the evolution of PLC technology over the last few decades.

<div class="htmlview paragraph">This paper reviews the characteristics of a power line network as data communication medium and studies the challenges encountered when communicating over power wiring. This technology review has been done as part of feasibility study for using aircraft power-lines for data communication.</div> <div class="htmlview paragraph">Power-Line Communication is a term which describes the use of existing electrical lines to provide the medium for a high speed communications network. Power Line Communications is achieved by superimposing the voice or data signals onto the line carrier signal using an appropriate communication technology. Power Line Communications represent a potential simplicity for communications among different devices, because it does not need additional wires for connecting devices network together.</div> <div class="htmlview paragraph">Power line cables have been used as a communication medium for many years. However, because power line cables are not designed for communication, they pose major challenges for a modem designer. Frequency selectivity and time variation of the channel frequency response, high level of noise, and regulatory issues are some of the main considerations. The impedance, transmission line loss and noise level of power line fluctuate greatly according to how the devices are connected and their operating conditions. The paper reviews these sources of attenuation, noise and distortion encountered when communicating over power wiring. The power-line communication channel, in general, is modeled as having a time varying frequency-dependent signal-to-noise ratio over the communication bandwidth.</div> <div class="htmlview paragraph">The paper further discusses the required features for aircraft data networks and presents aircraft power lines channel characteristics. The aircraft power-line was initially designed to distribute power in an efficient way, hence it is not adapted for communication and advanced communication methods are needed. Baseband techniques are not acceptable for Power Line Communications over aircraft power networks because of high powers transferred in baseband. This means some kind of passband technique has to be used. There exist a few types of digital modulations acceptable for this type of application. These can be split into narrowband and broadband. Narrowband mostly uses single carrier modulations like Frequency Shift Keying or Phase Shift Keying. Broadband modulations can be selected from Direct Sequence Spread Spectrum or Orthogonal Frequency Division Multiplex. The paper assesses these technologies in light of the known channel conditions and discusses realization of reliable high-speed communication over aircraft power-lines.</div>

The paper presents a methodology proposal for testing and evaluation of communication systems in Smart Grids, especially for Power Line Communication (PLC) systems. The PLC technology is widely used in power grid as a part of Advanced Metering Infrastructure (AMI) allowing mainly data transfers between a management system at utility and customer-premises smart meters. However, the PLC technology on medium voltage (MV) lines is often used for remote control and monitoring of distribution transformers as well. Since power grid and consequently power lines have different transmission parameters affected by their placement and potentially burdened by interferences, the PLC systems have to be evaluated on site before placed to production. In this paper, authors propose a methodology for long-term benchmarking of the PLC systems using newly developed testing tools. The methodology is subsequently tested on real power grid and a selection of results is presented.

Advanced Metering Infrastructure (AMI) is the foundation of the Smart Grid system. One of the most important parts of AMI is smart meter communication. Power Line Communication (PLC) technology utilizes the existing power line network for communication media between smart meters and Data Collector Units (DCU). One of the biggest challenges of communication using PLC is the noise level due to residential loads. In this study, laboratory test set up to measure noise caused by PV rooftop and residential loads are observed. Each PLC frequency band was measured and observed to determine the suitable frequency for PLC communication which was the low noise level. Some experiments in the field were conducted to determine the performance of the PLC. Laboratory test measurement result shows the FCC band (150-490 kHz) was outside the range of PV rooftop and residential load noise. On the other hand, the Cenelec A (35-90 kHz) frequency range was in the range of noise signal. Therefore, NB-PLC G3 using FCC frequency band was proposed to achieve robust data communication and lower noise level. G3 PLC FCC band was tested in the real field residential area, the experimental results showed 97.62% successful rate within one-week data collection.

Power line communication (PLC) technology has proved itself in the last decade as an interesting solution for data transmission and communication in domestic application. Lately, this technology has been considered as a potential solution for monitoring and diagnosis of a motor-fed inverter setup. Information issued from sensors would be sent via power cables back to the controller despite the harsh environment and the switching of the inverter. This paper discusses the use of PLC technology over a pulsewidth modulation network by underlining the effect of the power cable length and the inverter switching on communication. A new approach based on the measurement of scattering parameters is used for this purpose, and the effect of the cable length is analyzed. It is shown that, for long distances, the PLC technology may not be effective, and hence, it is not possible to use power cables for communication.

Communication is the transfer of information from one point to another over a channel. However, as technology is growing, more information is needed to be passed over large distances for the realization of the world being a global village. There is the need to place a reliable communication system that will transmit effortlessly both data and voice over a channel. Power Line Communication (PLC) also known as Broadband over Power Line (BPL) technology offers high speed and broadband communication services to homes connected to the power lines. This makes use of the electrical lines for transmission of data up to the last mile and there is no need of separating copper cables, short haul satellite systems, optical fibre cable and Wi-Fi. This work presented an overview of a voice and data communication over PLC in terms of the various types, equipment use, method of communication, application, regulatory activities on PLC and the challenges facing the implementation of power line for transmitting voice and data. Therefore, PLC is a viable alternative to all other methods of transmission as it is readily available and can be easily implemented in rural areas where other communication systems are not implemented for the transmission of voice and data communication. Keywords: Communication, Power Line Communication, Broadband over Power Line, Voice and Data Communication, Broadband over Power Line, Transmission, Electrical Line. DOI : 10.7176/MTM/9-8-03 Publication date : August 31st 2019

Based on the techno-economic pedagogical (TEP) method proposed in [1] that is suitable for designing Broadband over Power Lines (BPL) networks in transmission and distribution power grids, this paper examines the broadband potential of overhead low-voltage/broadband over power lines (LV/BPL) and medium-voltage/broadband over power lines (MV/BPL) networks. In this paper, on the basis of the set of linear simplifications and techno-economic metrics already presented in [1], TEP method demonstrates to undergraduate electrical and computer engineering (ECE) students the behavior of overhead LV/BPL and MV/BPL networks in terms of their modal transmission characteristics when different overhead LV/BPL and MV/BPL topologies occur. The contribution of this paper is four-fold. First, the factors influencing modal transmission characteristics of overhead LV/BPL and MV/BPL networks are investigated with regard to their spectral behavior and end-to-end channel attenuation. Second, the impact of the multiplicity of branches at the same junction is first examined. In the light of cascaded two-way power dividers, TEP method is extended so as to cope with more complex BPL topologies offering a new simplified and accurate circuital approximation. Third, apart from the broadband transmission characteristics of the entire overhead distribution power grid, a consequence of the application of TEP method is that it helps towards the intraoperability/interoperability of overhead LV/BPL and MV/BPL systems under a common PHY framework in the concept of a unified distribution smart grid (SG) power network. Fourth, TEP method can be demonstrated to undergraduate ECE students as case study in order to stimulate their interest for Microwave Engineering and Circuit/System Engineering courses. Citation: Lazaropoulos, A. (2015). Designing Broadband over Power Lines Networks Using the Techno-Economic Pedagogical (TEP) Method – Part II: Overhead Low-Voltage and Medium-Voltage Channels and Their Modal Transmission Characteristics. Trends In Renewable Energy, 1 (2), 59-86. doi: 10.17737/tre.2015.1.2.006

Although Power Line Communication (PLC) is not a new technology, its use to support data transmission over low voltage (LV) distribution networks is still the focus of ongoing research. This thesis focuses on the channel modelling and performance evaluation of narrowband (NB) PLC system. First, the channel modelling approaches of PLC are studied. Then, the proposed PLC channel modelling method based on the bottom-up approach for LV narrowband PLC in a frequency band between 9 kHz and 490 kHz is presented. This proposed model employs the transmission and scattering matrix methods to calculate the transfer function of a typical LV PLC network which comprises two common cable types (copper cables and aluminium conductor steel reinforced). Unlike the top-down approaches, this model is scalable as the network complexity increases and can better describe the network behaviour as a function of physical parameters.In addition, the noise characteristics and popular noise reduction techniques of PLC are studied. The major impairment to the PLC is the impulsive noise which is mainly generated by the switching transient in the network. Hence, a new technique is proposed to mitigate the impact of impulsive noise on data transmission over power lines. This proposed technique is an optimal Clipping/Blanking nonlinearity technique which is based on the minimum bit error rate (BER) search. Results obtained from the simulation of this technique demonstrate that performance has been enhanced in the NB-PLC system. The performance of the narrowband PLC system is also evaluated in both physical (PHY) and medium access control (MAC) layers. Since Orthogonal Frequency Division Multiplexing (OFDM) is a suitable modulation scheme for hostile environment of the power line, it is used to evaluate the PHY layer performance. As a result of the PHY layer performance analyses, it is found that the BER performance between neighbouring points in the typical LV PLC network is reasonable, but communication beyond one hop have to rely on upper layer protocols. In the MAC layer performance evaluation of the PLC system, the widely known random access MAC protocol that uses the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) will be utilised. The MAC performance evaluation of the PLC system demonstrates a significant packet loss in LV PLC network even with a light traffic condition due to the noisy channel. Furthermore, the goodput declines abruptly once the individual transmission rate is high enough to block the network. In addition, the simulation results show that the channel errors can be reduced by adjusting the MAC parameters to allow the re-transmissions mechanisms to recoup the lost packets.

The hybrid wireless and power line communication (PLC) technology greatly improves the reliability of Power Internet of Things network (IoT) and the access ability of the terminals. However, with the development of Power IoT, the topology structure of the network becomes exceedingly complex, and the difficulty of networking is also gradually increasing. To address this issue, this paper proposes a multi-ant colony (MACS) based QoS networking algorithm for hybrid PLC and wireless communication networks. Considering the network QoS parameters and service demands, the networking algorithm constructs the fitness function to evaluate the quality of communication transmission paths, and the MACS algorithm is employed to establish the optimal relay route to complete networking. Numerical results prove that the MACS algorithm has a superior ability to jump out of local optimum than the traditional improved ant colony system (IACS) algorithm. Moreover, our proposed algorithm can construct the optimal relay route under corresponding constraints and demands according to different types of services.

Power line communications (PLCs) refer to a technology based on the existing electrical wiring to transmit data among the devices connected to the network. The PLC technology is an excellent solution widely studied and analysed by researchers, even in those areas characterized by strict requirements, such as industries. In this paper, a technique based on fuzzy logic, for the dynamic management of the amplitude of the signal emitted by the devices of a power line network, is proposed. The main aim is to manage the amplitude of the transmission signal in order to reduce the noise introduced into the network, and, as a consequence, the power consumption, increasing data transmission quality of network in terms of Quality of Service (QoS). This solution has been implemented into embedded systems based on the ADD1010, a power line System on Chip (SoC), and tested through a real scenario realized in laboratory.

Power Line Communications (PLC) is regarded as the promising home networking technology for smart grid application since the PLC technology enables data transmission via the existing power line. The cooperation between PLC and Wireless Local Area Network (WLAN) will be an effective hybrid solution for Home Area Networks (HANs). In this paper, we consider that Transmission Control Protocol (TCP) packets are transmitting in heterogenous communications network based on PLC and WLAN. The existing TCP congestion control has low effectiveness due to the error-prone power line channel. Therefore, we propose an adaptive rate control to improve TCP performance in the hybrid PLC/WLAN HANs. We exploit the communications mechanism of WLAN to improve the PLC link utilization. The methodology of Heuristic Dynamic Programming (HDP) is employed to obtain the optimal rate policy. The bottleneck link capacity is estimated by neural network training. The sending rate is adapted according to the long-term quality of service (QoS) of applications. Simulation results illustrate that the proposed rate control effectively filters out the negative impact from the instantaneous impulse noise in PLC channel and outperforms the existing TCP.

This work aims at measuring, characterizing, and analyzing hybrid channels for mobile data communication with power line communication (PLC) technologies. These channels denote the concatenation of power line and wireless as only one channel. A measurement setup and OFDM-based technique for channel estimation were applied to carry out a measurement campaign of hybrid channels in the PLC → wireless and wireless → PLC directions. Preliminary results as well as analysis when estimates of the hybrid channels cover the frequency band between 1.7 up to 100 MHz are presented. The attained results reveals that these hybrid channels are very challenging ones. Also, they could be useful for data communication if more investigation concerning the PLC coupling device, the antenna geometry, and theoretical formulation for the signal propagation through the hybrid channel is deeply investigated.

Structural Health Monitoring of distributed systems is closely connected with data transmission from measurement points to the main server, where measurement data is processed and subjected to expert assessment. Power Line Communication (PLC) technology allows data transmission through existing power network. The greatest advantage of the PLC technology is the possibility of using ubiquitous, electric infrastructure, wherever there is no access to dedicated wired transmission links. However, it should be stressed that the main application of power lines is transmission of electricity while data transmission is a secondary issue. In monitoring systems and distributed measurement systems it is of vital importance that information from measurement points reaches the receiver in the unchanged form. Hash functions rise possibility of proper recognition if transmitted data is an exact mapping of information sent from measurement point. The paper concerns the method of polynomial hash function implementation for PLC systems in the LabVIEW environment.

PLC (power line communication) technology is widely used in smart grid, this article details the power line channel characteristics of the environment, and its noise model can be divided into five categories. With analyzing their causes, bandwidth and respective property, we compare the advantages and disadvantages of the broadband and narrowband PLC technology in terms of the communication performance. And the major application scenarios in smart grid were divided into three different types: power information collection and the monitoring of electrical equipment, indoor devices interconnecting for smart home and broadband access. We are focusing on the topology and technical characteristics in the electric energy data acquisition system. Finally, the paper investigated the requirement of electric energy data acquisition system in China for smart grid.