Study of Possible Far Field EMI Impacts through High Speed Powerline Communication

If the impact of unwanted radiated HF signals from Powerline Communication (PLC) Systems to the far field has to be investigated, the assumption of field strength decreasing proportional to 1/r is common practice in many theoretical studies. However, the standard measuring distance is r0 = 3 m, so far field conditions are not met over a great portion of the relevant spectrum from 1.5 to 30 MHz. As the power supply grid is a very complex environment, reliable data can only be obtained from detailed measurements, which are not yet avail able with a sufficient statistical basis. This paper first reviews some simulation results for propagation to the far field and, in the main part, concentrates on the experimental verification of the 1/r approximation for field strength depending on distance.