A Repeater Fault Locator Using a Correlation Technique for a Submarine Coaxial Cable System

This paper introduces a correlation technique in order to accurately measure intermodulation products from repeaters within a short period of time. A pair of PN sequences, whose cross-correlation function has a zero sidelobe has been designed to reduce interference by other products, and to obtain the necessary signal-to-noise ratio (more than 50 dB). As an example, design objectives and results for a repeater fault locator in a 140 MHz submarine coaxial cable system are described.