Researchers at Oklahoma State University (OSU) have been supporting studies with the Federal Aviation Administration for years. Currently, the groups are combing resources through the use of drone research.
Team members from the University’s Unmanned Systems Research Institute and the FAA are exploring electromagnetic modeling and calibration using unmanned aircraft systems (UAS).
FAA’s Flight Program Operations is researching opportunities to expand the development of UAS to calibrate light and radiofrequency signals. Such research could streamline facility inspection times and better use existing resources. Four different kinds of instrument landing systems are undergoing research: localizers, glide slopes, very-high-frequency omnidirectional ranges (VORs) and distance-measuring equipment.
Employees in Flight Program Operations have been preparing to significantly reduce uncertainty in measuring the signal strength of such equipment for several years. Upon reaching the limits of what can be accomplished with a two-dimensional measuring scheme, the Flight Inspection Airborne Processor Application (FIAPA) has now added programming flexibility, helping with corrections in all three dimensions and for frequency dependence.
As the next phase of work is developed, flights tests will be used to validate the data gained in the University of Oklahoma’s (OU) research, as the capability of FIAPA increases the size in which data is captured. Efforts are currently underway to develop a more efficient scheme for organizing this intelligence. Future plans will incorporate complex 4D correction tables into FIAPA and will complete a normal operational test-and-evaluation process, assessing the expected reduction in signal strength uncertainty.
Once a UAS method of measuring signal strength is developed, it will be used to evaluate the signal strength variation at the airborne reference point with each setup of portable base stations at the same locations and in the same orientations. This testing is likely to involve the changing atmospheric conditions. If the resulting variation of signal strengths is within tolerances, using the portable base station operationally with UAS measurement flights to confirm the signal strength of airborne reference points may be possible.
Flight Program Operations at the Aeronautical Center has achieved great success during this collaboration with the Oklahoma universities thus far. The team joined forces to build an OSU ground station to reference signals for calibration. Also, the team conducted three measurement campaigns, including multiple UAS flights at 1,500 feet. In addition, Aviation Technology Group Manager Brad Snelling co-authored a white paper, “Evolving to 4D Signal Strength Normalization,” which discusses ongoing efforts to reduce signal strength uncertainty via implementation of a 4D correction scheme.
The Aeronautical Center and Flight Program Operations is grateful to both universities for the value they have added to the ongoing applied research and for supporting FAA’s core business – safe flight operations.
