Gain Measurements at Power Supply Networks in the Short Wave Frequency Range

摘要

Power supply networks, especially in-house networks, offer an excellent topology with respect to wire-bound communications, an aspect which is currently fostering the deployment of wide-spread Powerline Communication (PLC) technology. However, as the cables are generally unshielded, a certain portion of an injected high frequency signal is emitted as radiation. Thus, when considering EMC aspects, a PLC network must be regarded as a distributed antenna. Due to the complexity of the antenna structure a simulation-based analysis is hardly feasible with acceptable accuracy. The empirical alternative is to determine the antenna properties by measurements. In this context, the antenna gain is an important figure, which has been of special interest for recent studies of cumulative PLC far field radiation. Currently, the main drawback of this method is a lack of sufficient measurement data, i.e. a statistically relevant basis is not available so far. Therefore, the work reported in this paper aims at a fast measurement and evaluation procedure, enabling the acquisition of antenna gains for numerous and various power supply networks. The results show that gain values of -40 dBi at f < 10 MHz and-30 dBi at f > 10 MHz, respectively, are good estimates for statistical simulations of radiation from extended PLC activity.