Application and demonstration of a knowledge-based approach to interference rejection for EMC

This paper discusses the application and demonstration of a knowledge-based approach to performing interference cancellation for a collection of RF spread spectrum, frequency hopped transceivers co-located on an airborne platform. An expert system pre-processor is used to set up the initial problem and in particular, to provide a fully-validated geometry which is used to compute geodesic losses in the frequency domain. The expert system is then used to `monitor' the signal environment in the time domain and select the interference rejection scheme(s) appropriate for mitigating the effects of interferers present at a victim receptor port. The problem is that a single interference rejection scheme cannot be expected to suppress all types of interference that may be present. Computer simulations were conducted to demonstrate the effectiveness of the approach for several interference scenarios using the Electromagnetic Environment Effects EXpert Processor with Embedded Reasoning Tasker (E³EXPERT). This work was sponsored by the US Air Force Research Laboratory/IFSA under Contract F30602-97-C-0162.