US 12,111,428 B2
Acoustic distance ranging system
David Grant Cason, Palatine, IL (US); and Mark Gilbert, Palatine, IL (US)
Assigned to Shure Acquisition Holdings, Inc., Niles, IL (US)
Filed by Shure Acquisition Holdings, Inc., Niles, IL (US)
Filed on Dec. 1, 2021, as Appl. No. 17/457,139.
Claims priority of provisional application 63/120,050, filed on Dec. 1, 2020.
Prior Publication US 2022/0171042 A1, Jun. 2, 2022
Int. Cl. G01S 7/536 (2006.01); G01S 15/34 (2006.01)
CPC G01S 7/536 (2013.01) [G01S 15/34 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method comprising:
operating an audio transmitter and an audio receiver using a common clock,
transitioning, by the audio transmitter and at a first point in time, an audio ranging signal in a phase-continuous manner from a first frequency to remain at a second frequency for a predetermined duration;
receiving, at a second point in time and by the audio receiver, the audio ranging signal transitioned from the first frequency to remain at the second frequency;
determining a distance between the audio transmitter and the audio receiver based on: (1) a difference between the first point in time and the second point in time, and (2) a determined speed of sound;
transitioning, by the audio transmitter and at a third point in time, the audio ranging signal in a phase-continuous manner from the second frequency to remain at a third frequency;
receiving, at a fourth point in time and by the audio receiver, the audio ranging signal transitioned from the second frequency to remain at the third frequency; and
correcting the distance to a modified distance between the audio transmitter and the audio receiver, comprising:
measuring a duration of the transmission of the audio ranging signal at the second frequency, the duration comprising a difference between the fourth point in time and the second point in time;
determining a correction to the distance based on a comparison between the measured duration and the predetermined duration; and
updating the distance to the modified distance based on the correction.