A Method of Detecting Significant Sources of Intermodulation Interference

A method of detecting significant sources of ship topside intermodulation is presented which represents a major extension in capability and ease of use. The method involves a two-frequency test procedure and the use of elementary direction finding techniques. Deliberate concentration on interfering signals of the high order is the basis of the method. A computational scheme is presented which permits the determination of the lowest intermodulation product or order contributing to a given interfering signal.