High Speed Data Transmission using Earth Returning Circuit on Low-voltage Distribution Line

Abstract

We investigated the possibility of high speed data transmission using earth returning circuit on low voltage distribution line. It is expected that high quality and high speed acquisition of distribution facilities and customers data will be indispensable near future because of Demand Side Management etc. However at present, the data transmission rate on distribution line is about 100 bps by narrow band FSK or PSK. We use spread spectrum communication which is thought to be suitable for relatively low S/N. In this paper, we measured the transmission characteristics of earth returning circuit to make a model of transmission characteristics. We also measured the BER-E_b/N₀ characteristics both on outdoor model distribution line and on indoor simulator to confirm the transmission rate of 9600bps with the reach of 100m by direct spread spectrum modem. However, if we make use of this modem on actual distribution facilities, emission regulation and leakage voltage into customers' facilities must be taken into account.