Performance Evaluation for Medium Voltage MIMO-OFDM Power Line Communication System

Power line communication(PLC)provides intelligent electrical functions such as power quality measurement,fault surveys,and remote control of electrical network.Most of research works have been done in low voltage(LV)scenario due to the fast development of in-home PLC.The aim of this paper is to evaluate the link-level performance of a medium voltage(MV)MIMO-OFDM communication system based on transmission link under underground power line channel.The MIMO channel is modeled as a modified multipath model in the presence of impulsive noise and background noise.We first perform a measurement on the practical MV MIMO channel parameters for a section of buried cable of 1 km long in Ganzhou city,Jiangxi province,China.Based on the measured channel,we design the frame structure based on an IEEE standard for broadband over power line networks[1]to support MV MIMO-OFDM transmission.According to designed frame structure,we design an encoder and a decoder for a dual binary tail-biting turbo code and optimize some key decoder parameters for low bit error rate performance.Finally,the link-level performance for both spatial multiplexing and spatial diversity are evaluated.Numeral results show that MV MIMO-OFDM is a promising approach to provide both high data rate and link reliability for PLC.

A FAST BIT-LOADING ALGORITHM FOR HIGH SPEED POWER LINE COMMUNICATIONS

Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology. According to the real situation of the transmitting power spectrum limited in high speed power line communications, this paper explored the adaptive bit loading algorithm to maximize transmission bit number when transmitting power spectral density and bit error rate are not exceed upper limit. With the characteristics of the power line channel, first of all, it obtains the optimal bit loading algorithm, and then provides the improved algorithm to reduce the computational complexity. Based on the analysis and simulation, it offers a non-iterative bit allocation algorithm, and finally the simulation shows that this new algorithm can greatly reduce the computational complexity, and the actual bit allocation results close to optimal.

Modeling of OFDM Based Transceiver for Broadband Powerline Communication

In the recent past power line communication has emerged as an attractive choice for high speed data transfer and is looked upon as inexpensive and reliable media suitable for broadband internet access, home and office automation, in-vehicle data communication etc. In this paper we present an architecture for the physical layer of a PLC transceiver based on Orthogonal Frequency Division Multiplexing (OFDM) and the impact on multipath distortion for PLC transmission in terms of bit error rate. Since there is no standard PLC channel model available, a widely accepted multipath channel model is used for simulation purpose. Simulation results as well as FPGA synthesis verify the effectiveness of the proposed architecture for PLC modem design at 110 Mbps data rate.

Modeling Transfer Function of Electrical Power Lines for Broadband Power Line Communication

The indoor access network is characterized by several branches that cause many reflections. In this paper, we present an approach to model the transfer function of electrical power lines for broadband power line communication. The assuming channel consists of three wires, which is widely used in many countries. As an application of the proposed method, the effect of line length from transmitter to receiver, branched line length and number of branched are also studied. From the frequency response of the transfer function (magnitude and phase), it is seen that the position of notches and peaks in the magnitude responses are largely affected in terms of attenuation by the electrical network which consists of 15 branches.

Low Complexity Discrete Bit-loading for OFDM Systems with Application in Power Line Communications

Adaptive bit-loading algorithms can improve the performance of OFDM systems significantly. The tradeoff between the performance of the algorithm and its computational complexity is essential for the implementation of loading algorithms. In this paper, we present a low complexity non-iterative discrete bit-loading algorithm to maximize the data rate subject to specified target BER and uniform power allocation. Simulation results show that the proposed algorithm outperforms the equal-BER loading and achieves similar rates to incremental allocation, yet with much lower complexity.

Data Logging and Control of a Remote Inverter Using LoRa and Power Line Communication

For decades, the power system was highly centralized. With the growing integration of distributed generations into the system, there is a necessity for bi-directional communication methods to monitor and control the remote assets. The primary objective of this paper is to develop a communication link for monitoring and controlling a grid-connected inverter in a remote location. Furthermore, the paper presents developments that have been incorporated to improve the communication link. The literature survey indicates that LoRa is superior compared to other technologies, but has some security and reliability issues. This paper also presents an encryption algorithm to improve the security of the LoRa link. Local data storage added to the system before transmitting data increases the system reliability. A display at the transmission end is added to improve the user-friendliness of the communication link. A Powerline Communication link is parallelly added to the LoRa link to improve the reliability. Finally, tests are conducted with an actual inverter and the results are presented. The tests show that the developed communication link has improved security and reliability, while its open nature makes it highly scalable and adaptable for employment in other smart grid applications.

Traffic Modeling of a Finite-Source Power Line Communication Network

Power line communication (PLC) is a promising smart grid application for information transmission using existing power lines. We analytically model a finite-source PLC network subject to channel failure through a queueing theoretic framework. The proposed PLC network model consists of a base station (BS), which is located at a transformer station and connected to the backbone communication networks, and a number of subscriber stations that are interconnected with each other and with the BS via the power line transmission medium. An orthogonal frequency division multiplexing based technique is assumed for forming the transmission channels in a frequency spectrum. The channels are subject to failure during service due to noise. We determine the steady-state solution of the proposed model and derive a set of performance metrics of interest. Numerical and simulation results are presented to provide further insights into the analytical results. The proposed modeling method is expected to be used for evaluation and design of future PLC networks.

A Power Line-delivered and Lamp-based Broadband Mobile Communication System

A new mobile communications network architecture is proposed to solve four existing bottlenecks that restrict the rapid development of mobile communications,as well as to meet the development demands of future broadband mobile communications. The architecture introduces the Information Lamp (IL),a novel device carrying out transceiver function,as the access point,besides providing light. It fulfills information interaction between the access points and radio access network through the power line (or fiber). The new system,supported by core technologies such as multi-antenna based distributed space-time signal processing and distributed radio resource management,integrates the wired and wireless networks to provide high-speed and high-quality mobile communication services.

Power Line Communications Networking Method Based on Hybrid Ant Colony and Genetic Algorithm

When solving the routing problem with traditional ant colony algorithm, there is scarce in initialize pheromone and a slow convergence and stagnation for the complex network topology and the time-varying characteristics of channel in power line carrier communication of low voltage distribution grid. The algorithm is easy to fall into premature and local optimization. Proposed an automatic network algorithm based on improved transmission delay and the load factor as the evaluation factors. With the requirements of QoS, a logical topology of power line communication network is established. By the experiment of MATLAB simulation, verify that the improved Dynamic hybrid ant colony genetic algorithm (DH_ACGA) algorithm has improved the communication performance, which solved the QoS routing problems of power communication to some extent.

WAVELET-BASED OFDM-CDMA HIGH SPEED POWER LINE COMMUNICATION SYSTEMS

This letter derives the Equivalent M-band Discrete Wavelet(EMDW) transmission mode of Orthogonal Frequency Division Multiplexing(OFDM) transmission systems, and presents a new Quadrature M-band Discrete Wavelet(QMDW) based OFDM-CDMA(Code Division Multiple Access) communication systems for high speed Power Line Communication (PLC) channels.This system gives much better robustness to Inter-Channel Interference (ICI), Multi-User Interference (MUI) and noise interference, which is verified by simulation.

基于门限判断机会调度的多用户PLC/RF系统性能分析

针对融入译码转发中继技术的混合电力线通信(Power Line Communication, PLC)与射频(Radio-Frequency, RF)传输系统,首先提出了一种基于门限判断的多用户机会调度方案。其次,在PLC和RF链路信道衰落分别服从对数正态分布和相关莱斯分布的条件下,推导出采用所提调度方案的PLC/RF系统中断概率和归一化平均反馈负载的闭合表达式。接着,还通过分析高信噪比条件下系统中断概率的渐进性能,得到系统分集度和阵列增益的简单闭合表达式。最后,计算机仿真不仅验证了理论分析的正确性,而且进一步揭示了所提方案能够在尽量减少反馈负载的同时获得较优的中断性能,从而为实际的系统设计提供参考和依据。

基于改进压缩感知的宽带低压PLC系统脉冲噪声抑制算法

为解决宽带低压电力线通信(Power Line Communication,PLC)系统中脉冲噪声造成的通信性能不稳定、误比特率高的问题,针对正交频分复用的宽带低压PLC系统提出了一种改进压缩感知的脉冲噪声抑制算法,综合考虑了脉冲噪声恢复精度和时间复杂度去改进先验支撑集获取精度和压缩感知恢复步长。首先,利用改进的门限在接收端筛选出脉冲噪声的先验部分支撑集;其次,将频域的空子载波数据当作观测向量建立压缩感知方程,利用改进的稀疏度自适应匹配追踪算法恢复脉冲噪声;最后,通过减去恢复的脉冲噪声对接收信号进行抑制。仿真结果表明,与传统算法对比,所提算法具有较好的误比特率性能,并在较高信噪比时有更好的恢复性能。

Cross-layer Resource Allocation on Broadband Power Line Based on Novel QoS-priority Scheduling Function in MAC Layer

Traditional resource allocation algorithms use the hierarchical system, which does not apply to the bad channel environment in broadband power line communication system. Introducing the idea of cross-layer can improve the utilization of resources and ensure the QoS of services. This paper proposes a cross-layer resource allocation on broadband power line based on QoS priority scheduling function on MAC layer. Firstly, the algorithm considers both of real-time users’ requirements for delay and non-real-time users’ requirements for queue length. And then user priority function is proposed. Then each user’s scheduled packets number is calculated according to its priority function. The scheduling sequences are based on the utility function. In physical layer, according to the scheduled packets, the algorithm allocates physical resources for packets. The simulation results show that the proposed algorithm give consideration to both latency and throughput of the system with improving users’ QoS.

基于译码转发的PLC-VLC/RF混合传输系统中断性能分析

针对译码转发(Decode and Forward,DF)协议下室内电力线通信(Power Line Communication,PLC)-可见光通信(Visible Light Communication,VLC)/射频(Radio Frequency,RF)的混合传输系统,考虑接收端采用最大比合并(Maximal Ratio Combining,MRC)和选择合并(Selection Combining,SC)两种方案,并分析这两种方案下的系统中断性能。首先,在考虑路径损耗、信道衰落和用户随机分布的情况下,分别给出MRC和SC两种方案的输出信噪比表达式。接着,推导出这两种方案下系统的中断概率闭合表达式。最后,利用计算机仿真验证理论分析的正确性,分析不同参数对系统中断性能的影响,从而为PLC-VLC/RF混合传输系统的实际应用提供理论依据。

Smart Home Networking: Lessons from Combining Wireless and Powerline Networking

Integrating the power grid technology with renewable power generation technologies, Demand Response (DR) programs enabled by the Advanced Metering Infrastructure (AMI) were introduced into the power grid in the interest of both utilities and residents. They help to achieve load balance and increase the grid reliability by encouraging residents to reduce their power usage during peak load periods in return for incentives. To automate this process, appliances, in-house sensors, and the AMI controller need to be networked together. In this paper, we compare mainstream network technologies applicable to home appliance control and propose a solution combining Power Line Communication (PLC) with wireless communication in smart homes for the purpose of energy saving. We extended NS-2, a popular network simulator, to model such combined network scenarios. Using a number of different routing strategies, we then model and evaluate the network performance of DR programs in smart homes in such a combined network.

基于PLC及电力线载波技术的园区照明控制系统

针对目前国内大部分园区照明控制采用的时控器、人工巡检、无控制策略等自动化程度低,能源浪费等问题,为响应国家节能减排,该文针对传统园区道路照明和车库照明提出了一种基于PLC和电力线载波技术的园区智能照明控制系统,并在上海武宁园区进行实际应用,达到了高效节能效果。该控制系统采用可视化集中控制,传感器和实际作息策略相结合等智能控制管理,通过以太网和电力线载波的通信方式和监控平台建立通信,实现园区路灯节点、车库照明与监控中心之间的实时数据通信,实际应用验证了该控制系统能够实时采集环境参数,实现按时按需照明,能源利用率提高了30%,验证得出该文提出的控制方式大大提高了园区照明的智能化水平。

G3-PLC Keepalive网络维护机制设计

电力线载波通信技术是构建智能电网的重要手段,作为国际公认的技术标准,现有的G3-PLC标准并未规定具体的网络维护方法。该文提出了一种新型Keepalive网络维护机制,该机制同时考虑时效性和可靠性,在保证路由重启后表端能及时入网的基础上,确保了单次未能重入网模块能在较短时间内恢复正常工作状态。该机制在正常工作状态亦可进行网络维护,可协助路由端确认拓扑状态、掌握相位讯息,在链路失效时加速表端确认速度。该机制已通过Vango V63xx+V6000平台确认可行性,对于提高G3-PLC电力线载波通信网络稳定性有一定的实用意义。

动力电池分选模组线PLC信息传递的程序设计与分析

随着智能制造技术的发展和工业机器人技术的普及,柔性制造作为一种先进的低成本生产方式,成为企业降低消耗和提高生产效率的重要途径,有利于提升企业竞争力,满足客户的多样化需求。在某动力电池分选模组线项目中,从可编程逻辑控制器(Programmable Logic Controller,PLC)角度解析项目中的电芯信息的传递与流动,设计了一套完整的信息传递与流动方案。方案的主要功能是从上位机获取所需生产的模组信息,在一条产线上同时生产多种模组,按要求配组容量,组合出满足要求的产品。

智能电网应用中的PLC技术

智能电网已成为研究关注的热点、并代表未来电网的发展方向,信息与通信技术是其关键的促成因素,其中电力线通信(PLC)技术正发挥着愈来愈重要的作用。结合智能电网应用特点、以及近年来正交频分复用调制解调策略(OFDM)的发展,分析和阐述基于OFDM的高速窄带PLC技术,即PRIME与G3 PLC技术,包括其物理层与媒介访问控制层;同时考虑到PRIME与G3 PLC在互操作性方面的不足,论述了下一代新型窄带电力线通信技术G.hnem,包括其物理层G.9955与数据链路层G.9956;最后,总结得出相关结论。

基于PLC信道相关性的分集合并技术研究

研究电力线信道(power line channel,PLC)相关性对提高电力线通信系统的性能具有重要意义。基于电力线信道的多输入多输出(multiple input muliple output,MIMO)模型和信道本身的物理特性,可知电力线载波通信系统中信道间存在一定的相关性。详细分析了电力线信道单输入多输出(single input multiple output,SIMO)系统中子信道之间相关性及计算方式,同时也分析了电力线单输入多输出系统在分集合并技术下,采用二进制相移键控(binary phase shift keying,BPSK)调制方式时的最大比合并和等增益合并的系统误码率,比较了2种分集合并技术在不同的信道相关性下的误码率。通过仿真得出,相关性会影响分集合并的误码率,进而影响系统的性能。