EMIR: an expert system for electromagnetic interference resolution

Abstract

The increasing density and complexity of modern radio communications systems and the crowded electromagnetic environment make electromagnetic interference (EMI) a growing concern. To ensure electromagnetic compatibility (EMC) in Transport Canada (TC) installations, such as airports and air traffic control centres, improved methods for systems design, installation and maintenance are required. When Electromagnetic Interference is found to be a problem, immediate steps are taken to identify and resolve the interference which may be caused by radiation sources such as broadcast stations, air/ground transmitters, computing devices, vehicular electrical systems, etc.This paper discusses Phase I of a multi-phase project. EMIR (Electromagnetic Interference Resolution) is a rule-based project, sponsored by Transport Canada of the Canadian Government, through its Transportation Development Centre. The project encapsulated, an expert's knowledge and experience about Radio Frequency Interference (RFI) between radio communication systems in an expert system.EMIR reflects the standard diagnostic algorithm of hypothesis, test, and corrective measures; however, it contains a novel approach toward the treatment of the uncertainty of input data. EMIR removes the necessity of acquiring from the user the uncertainty associated with the responses. It uses the expert's experience to judge the relevance of the response to each individual interference. In addition, the system has a module which is automatically invoked when an anomalous situation occurs. This module not only allows the system to consider anomalies, it will also call for assistance from the expert when the situation appears to be outside EMIR's capability. Finally, the user interface is as helpful and easy to operate as possible, and the system is expandable into other EMI domains.