1. A method of collecting electromagnetic signals having a broad frequency spectrum over a large geographical area comprising: detecting said electromagnetic signals from an aircraft using a plurality of antennas that are tuned to a plurality of frequency bands to produce a plurality of frequency band antenna signals from said plurality of antennas; band pass filtering said frequency band antenna signals to produce a plurality of filtered frequency band signals; digitizing said plurality of filtered frequency band signals to produce digitized frequency band signals; analyzing said digitized frequency band signals to provide analyzed frequency band data regarding said electromagnetic signals.