As a pilot with an amateur radio license (though an inexperienced ham) this sounds really interesting. Could you elaborate more on building the VOR receiver?
The transmitter has an electronically switched antenna that virtually moves in a circle at 3600 rpm, causing FM modulation phased with direction. The carrier is also AM modulated with a reference phase signal.
I built a gnu radio flowgraph to receive both and display heading to the VOR.
I built a gnu radio flowgraph to receive both and display heading to the VOR.