An Overview of Broadband communication over Power Lines

Broadband over power lines are Systems for carrying data on conductors used for electric power transmission. Power line communication technologies can be used for different applications ranging from home automation to internet access. With the spread of broadband technologies in the last few years, there are yet significant areas in the world that do not have access to high speed internet, as compared with the few internet service providers in existence, the additive expenditures of laying cables and building necessary infrastructure to provide DSL in many areas most especially rural areas is too great. But if broadband is served through power lines considering the fact that it exist all over the country, there will be no need to build new infrastructure. Therefore, anywhere there is electricity, there could also be broadband. Broadband over Power line is designed to offer an alternative means to provide high speed internet access, voice over Internet protocol (VOIP) and other broadband services, using medium and low voltage lines to reach customers and businesses by combining the principle of wireless networking, modems and Radio. Researchers and developers have created ways to transmit data over power lines into homes at speeds between 500kilobits and 3 megabits per second which is equivalent to the cable DSL (Digital Subscriber Line) and this is achieved by modifying the present power grids with specialized equipments. With this knowledge, the broadband power line developers could partner with power companies and Internet service providers to bring broadband to everyone with access to electricity

INVESTIGATIVE STUDY OF VOICE AND DATA COMMUNICATION OVER POWER LINE COMMUNICATION SYSTEM

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 201

Širokopojasni prijenos podataka elektroenergetskom mrežom

The paper presents an overview to broadband over powe lines. Over the past few years advances in signal processing technology have enabled the advent of modem chips that are able to overcome the transmission difficulties associated with sending communications signals over electrical power lines. There are two predominant types of BPL communications configurations: Access BPL and In-Home BPL. One of the largest commercial markets for BPL is the ability to provide Internet Services by means of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocols. Another significant benefit of BPL is the ability to employ “intelligent” power line networks that make use of SCADA devices.U radu je opisan pregled širokopojasnog prijenosa podataka elektroenergetskom mrežom. Razvoj tehnologije prijenosa signala omogućio je prevladavanje problema prijenosa komunikacijskih signala putem elektroenergetske mreže. Time je omogućen širokopojasni prijenos podataka kojim se osigurava pristup Internetu koristeći postojeću infrastrukturu. Ovakva komunikacija dijeli se na: pristupnu i kućnu. Najveći ekonomski značaj ove tehnologije je mogućnost pružanja pristupa Internetu TCP/IP protokolom. Osim pristupa Internetu omogućava i implementaciju pametne elektroenergetske mreže (SCADA)

Effects of Power Line Communication on Radio Communication Equipment

Radio communication is a wireless transfer of information via power cable by Power Line Communication (PLC) and its dissemination through radio communication equipment.. However, this information causes signal interference, noise and distortion with the power line communication. This work analyzed the effect of PLC on radio communication equipment by interconnecting two high-speed PLC modems communicating with a data rate of up to 250 Mbit/s using telephone distribution wiring for radio spectrum to reduce the interference radiation that emanates from a power line. The measurements were made using a reference antenna at a distance of 3 m from the power line. The peak field-strength values were measured and recorded in the 30-350 MHz frequency range in horizontal and vertical polarization. The result shows that interference radiation occurring at frequencies up to 305 MHz, includes the FM band as well as the Digital Audio Broadcasting (DAB) band. It is expected that as the data rate of high speed modems increases, a corresponding increase in the interference radiation occurs at frequencies above 300 MHz. To this regard, administrations should take all practicable and necessary steps to ensure that the operation of power and telecommunication distribution networks do not cause harmful interference to a radio communication service. Keywords: PLC, Radio Communication, Interference, Noise, Distortion, Communication Equipment, Field Strength, DAB DOI: 10.7176/JNSR/9-16-04 Publication date: August 31st 201

On power line positioning systems

Power line infrastructure is available almost everywhere. Positioning systems aim to estimate where a device or target is. Consequently, there may be an opportunity to use power lines for positioning purposes. This survey article reports the different efforts, working principles, and possibilities for implementing positioning systems relying on power line infrastructure for power line positioning systems (PLPS). Since Power Line Communication (PLC) systems of different characteristics have been deployed to provide communication services using the existing mains, we also address how PLC systems may be employed to build positioning systems. Although some efforts exist, PLPS are still prospective and thus open to research and development, and we try to indicate the possible directions and potential applications for PLPS.European Commissio

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

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.2015.1.2.00

Smart Energy and Spectral Efficiency (SE) of Distribution Broadband over Power Lines (BPL) Networks – Part 2: L1PMA, L2WPMA and L2CXCV for SE against Measurement Differences in Overhead Medium-Voltage BPL Networks

This second paper assesses the performance of piecewise monotonic data approximations, such as L1PMA, L2WPMA and L2CXCV, against the measurement differences during the spectral efficiency (SE) calculations in overhead medium-voltage broadband over power lines (OV MV BPL) networks. In this case study paper, the performance of the aforementioned three already known piecewise monotonic data approximations, which are considered as countermeasure techniques against measurement differences, is here extended during the SE computations. The indicative BPL topologies of the first paper are again considered while the 3-30 MHz frequency band of the BPL operation is assumed.Citation: Lazaropoulos, A. G. (2018). Smart Energy and Spectral Efficiency (SE) of Distribution Broadband over Power Lines (BPL) Networks – Part 2: L1PMA, L2WPMA and L2CXCV for SE against Measurement Differences in Overhead Medium-Voltage BPL Networks. Trends in Renewable Energy, 4, 185-212. DOI: 10.17737/tre.2018.4.2.007

Smart Energy and Spectral Efficiency (SE) of Distribution Broadband over Power Lines (BPL) Networks – Part 1: The Impact of Measurement Differences on SE Metrics

This paper assesses the impact of measurement differences on the spectral efficiency (SE) of distribution broadband over power lines (BPL) networks when CS2 module is applied. The broadband performance of distribution BPL networks is investigated in the 3-88 MHz frequency range when appropriate injected power spectral density limits (IPSD limits) and uniform additive white Gaussian noise (AWGN) PSD levels from the BPL literature are assumed. The impact of measurement differences on SE of the distribution BPL networks is here assessed through appropriate SE metrics. These SE metrics assessing this impact are detailed in order to act as the benchmark metrics of the countermeasures techniques against measurement differences of the companion paper.Citation: Lazaropoulos, A. G. (2018). Smart Energy and Spectral Efficiency (SE) of Distribution Broadband over Power Lines (BPL) Networks – Part 1: The Impact of Measurement Differences on SE Metrics. Trends in Renewable Energy, 4, 125-184. DOI: 10.17737/tre.2018.4.2.007

Investigation into the impedance and communication requirements for the low voltage distribution line in the high frequency spectrum

Power Line Communications is long established for low data rate applications over high- voltage power lines. It is now charting new territory in high speed data transmission to the high frequency band of IMHz and upwards over the low-voltage segment below the distribution transformers.' Since the power line is designed for transmission of power instead of signal transmitting originally; it has many shortages when used as a signal communication channel. The heterogeneous structure of the power line network with numerous branches and impedance mismatcheS causing reflections and attenuations during signal transmission, and thus communication signal cannot be sent out or received completely. From this point of view, the power line impedance is a very important parameter in the design of power line communication (PLC) modem architecture, which is subject to legislations that limit the signals in the line. Variations on the impedance of the power line affect the communications channel performance. For the optimum modem design, power line impedance must be known. Power line impedance changes with time, carrier frequency, load variations, architectures and locations of the lines in city, urban, rural & industrial environment. The objective of this study is to determine the impedance of power distribution network in a frequency range from IMHz to 30MHz. This is in line with international standard bodies including CENELEC, IEC, ITV and ETSI, which stipulates that for propagation characteristics of power line and EMC regulations, data transmission rate are evolving and . are being extended all the time to data rate up to 100 Mbps. This thesis covers impedance measurements carried out in college buildings in Somerset, UK together with some residential houses in Somerset and London. The college buildings have both three-phase and single-phase architectures with various laboratories where loads are randomly switched on and off. An impedance analyser is used to carry out the measurements which performs a scan through a programmable frequency limits and acquires impedance parameters in the frequency domain Measurements were monitored using Microsoft Remote Desk Top client application Series of experimental measurements were carried out in the Bridgwater College and residential houses in Bridgwater and also in London. The first part of the thesis offers detailed introduction to the topics of electricity supply networks, power line communications, modulation techniques and electromagnetic compatibility, noise and transmission line characteristics. From the experimental results, presented in graphical format, a number of conclusions can be drawn. A wide range of impedances are observed for single phase measurements, within the range of 3 - 584 Ω for large buildings and residential houses. For three phase measurements impedances varied from 21 - 340 Ω. The thesis concludes with a suggestion of how these measurements may be used in PLC modem design. Dynamic output-impedance PLC modems may be designed using a real-time impedance detector of the power line and the adjustable output impedance-power amplifier. Therefore, modem output impedance may be matched to the real time line impedance

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