Radio Frequency (RF) System Performance and Electromagnetic Interference (EMI) in Dynamic Environments

The on-board and co-site EMI environment can be very severe for aircraft sensor and communications systems. The current state of the art in predicting on-aircraft RF performance and performance degradation from EMI (also known as co-site interference) utilizes physics-based modeling and simulation tools that consider a static or stationary environment. However, real world environments are dynamically changing on scales that lead to unpredicted system performance degradation that are a direct result of non-stationary conditions. The request for proposal (RFP) indicates that on-aircraft effects from blade (or other moving part) modulation are among the sources of interference that need to be quantified with respect to their impact on antenna pattern degradation, and associated system performance degradation. However, on-aircraft EMI conditions can vary significantly depending on antenna location on the platform and whether they mechanically and/or electronically rotate to perform their function. Another consideration is the inclusion intentional or unintentional off-board RF interference that can interact with the platform/sensor dynamics in ways that can vary with illumination geometry and platform trajectories. Scenarios that combine these conditions further complicate the co-site interference between on-board systems that must simultaneously operate. This SBIR effort will identify and categorize classes of EMI along with potential solutions that will include passive, active and hybrid passive-active techniques. In addition, a subset of these potential solutions will be identified for possible implementation within an adaptive sensor resource manager (RM) framework. Finally, modeling methods will be used to evaluate the effectiveness of a select subset of EMI mitigation techniques that are of relative near term value to EA-18G, SH-60R and the MQ-8B Fire Scout VTUAV operating scenarios.