# Broadband Power Line Communication for Integration of Energy Sensors within a Smart City Ecosystem
## 1 Introduction  
Broadband Power Line Communication (BPLC) technology is well known in the commercial and scientific spheres today. It is widespread in areas from home use via smart metering to industry solutions. BPLC technology is a separate part of the generally used term PLC (Power Line Communication) technologies. The main division of PLC technology is given by the frequency band i.e., Narrow Band (NPLC) and Broadband (BPLC) systems.  
Specific technology is chosen by the end use application. The real environment affects the functionality of a particular technology. The parameters of the power line (cable type) and the influence of possible interference (background noise) are essential communication parameters. Usability, due to the time and frequency invariance of several parameters such as power spectral density and line impedance, is limited. The predicted suitability of the technology and its specific configuration in particular applications are problematic depending on the specific deployment location. Available technologies resolve this problem by hardcoded settings of adaptive methods in better cases; in worse cases, there is only one configuration that the device works with. As a rule, this is the most robust communication mode. The Signal to Noise Ratio (SNR), or similar related quantities, is considered as one of the main parameters and channel quality indicators. For this reason, the values of this physical quantity are often used as a decision indicator to setup the configuration for communication. In practice this means that when the PLC system recognizes a low value of SNR, it chooses, for example, a modulation mode with fewer states, if this is possible. These processes are not perfect and if the changes are more frequent, the delay or stability of the communication may be even worse than without such an adaptation. Because of this, PLC does not always seem to be the most suitable candidate for a stableconnection for high-speed networks. The article does not focus on NPLC, mainly due to limited transmission speed, although NPLC systems are considered in smart grid and smart metering applications [1], presented in articles [2; 3; 4; 5]. NPLC technology is considered in the related works section. The paper is divided into four parts.  
The first part deals with approaches and possible ways of developing adaptive methods for PLC technology using a simulator. To create an adaptive method, it is necessary to design topologies in a simulation environment, where it is possible to perform experimental simulations. These simulations are based on mathematical models of the physical parameters of cables, background noise, attenuation and the number of communication devices.  
The second part demonstrates available works with experimental simulations of the BPLC technology with focus on smart grid and smart metering areas.  
The third part shows comparison of a real measurement and corresponding simulations. The scenarios considered in this work are taken from a real smart grid infrastructure.  
The fourth part demonstrates several experimental measurements of PLC systems under real or laboratory conditions. These measurements bring short and long term results in the form of specific data for evaluation of a specific PLC topology as to whether it suits the real infrastructure. Other parts of the paper deal with simulations of real scenarios using the NS-3 simulator. The first results of the simulated scenarios serve to verify the expected trend based on line distance. The second series of results correspond with the real smart grid infrastructure via which the measurements were taken. The main goal of the paper is to present a possible method of low-budget development of PLC systems with verification of suitability for end application before installation.