Whispering gallery mode based range-resolved air data system

A method of obtaining air data for a vehicle, the method comprising:

• emitting laser light pulses from a laser device on the vehicle;
• transmitting the laser light pulses through a set of transmit optics into an external air volume adjacent to the vehicle;
• collecting, by a set of receive optics, scattered portions of the laser light pulses from the external air volume;
• receiving, in a whispering gallery mode (WGM) frequency discriminator, the scattered portions of the laser light pulses from the receive optics, the WGM frequency discriminator including at least one WGM resonator, wherein the WGM resonator is controllable to have a variable resonant frequency;
• outputting a selected portion of the laser light pulses at one or more optical signal frequencies via tuning the WGM resonator other than by an electro-optic effect;
• sampling, with an optical detector, the selected portion of the laser light pulses from the WGM frequency discriminator;
• converting the sampled laser light pulses to one or more scalar values in the optical detector;
• and
• processing the one or more scalar values to obtain air data for the vehicle.

An air data system for a vehicle, the air data system comprising:

• a laser device on the vehicle, the laser device configured to emit laser light pulses;
• a set of transmit optics configured to transmit the laser light pulses from the laser device into an external air volume adjacent to the vehicle;
• a set of receive optics configured to collect scattered portions of the laser light pulses from the external air volume;
• a whispering gallery mode (WGM) frequency discriminator configured to receive the scattered portions of the laser light pulses from the receive optics, the WGM frequency discriminator comprising an array of WGM resonators with different fixed resonant frequencies and configured to output a selected portion of the laser light pulses at respective optical signal frequencies corresponding to the different fixed resonance frequencies;
• an optical detector configured to sample the selected portion of the laser light pulses from the WGM frequency discriminator, the optical detector configured to convert the sampled laser light pulses to one or more scalar values;
• and
• a processing unit operative to receive and record the one or more scalar values from the optical detector.