A Study of Producing an LCL Probe for Residential Power-lines
Although power-line communications are expected as a promising method to realize an in-home network, one of their difficulties is an unnecessary radiation due to the electrical unbalance of power-line channels. To solve the problem, the statistical data of electrical unbalance based on the measurement at the practical fields, i.e., many and various Japanese residential power-lines, must be collected as the first step. In this paper, a method to produce a longitudinal-conversion-loss˜(LCL) probe that can be used for the practical measurement is studied. The LCL is a measure of the electrical unbalance, and is often used to determine the impairment of EMC performance of a system by the cabling. To improve the dynamic range of the probe, an adjustment method of transformers’ parameters is proposed. According to our scenario, the obtained dynamic range was better than that of the conventional probe with the frequency band higher than 2MHz. The achieved improvement was 6dB at 6MHz, and 14dB at 30MHz, for example.