Patent ID: 9453901
Filing Date: 2016-09-27
CPC Classification: G01S

Claim Text:
1. A dual frequency ultrasonic locationing system, comprising: an emitter system operable to emit two different ultrasonic frequencies simultaneously in one ultrasonic burst; a receiver with at least two microphones each operable to receive the ultrasonic burst having the two different ultrasonic frequencies simultaneously; a correlator operable to correlate the signals obtained from each microphone to derive a time difference of arrival of the ultrasonic burst between each microphone, wherein the time difference of arrival of the ultrasonic burst from the emitter impinging on each microphone is utilized with a multilateration locationing technique to determine a location of the emitter in free space; and wherein the receiver also includes a multiplier for each microphone, wherein each multiplier multiplies the first and second frequency components from its respective microphone in the digital domain to provide the obtained signals for the correlator.