US 12,092,462 B1
Mitigating bias instabilities in optical gyroscopes
Nathan Abrams, Santa Clara, CA (US); Mario Paniccia, Santa Clara, CA (US); and Mike Horton, Santa Clara, CA (US)
Assigned to Anello Photonics, Inc., Santa Clara, CA (US)
Filed by Anello Photonics, Inc., Santa Clara, CA (US)
Filed on Apr. 3, 2024, as Appl. No. 18/626,209.
Claims priority of provisional application 63/495,513, filed on Apr. 11, 2023.
Int. Cl. G01C 19/64 (2006.01); G01C 19/10 (2006.01); G01C 19/66 (2006.01); G01C 19/72 (2006.01)
CPC G01C 19/661 (2013.01) [G01C 19/10 (2013.01); G01C 19/64 (2013.01); G01C 19/72 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An optical gyroscope comprising:
one or more phase modulators to operate on two counter-propagating beams to introduce a phase shift between the two counter-propagating beams before the two counter-propagating beams are interferometrically combined to generate a rotation signal;
a signal generator to generate a first modulation frequency and a second modulation frequency to drive the one or more phase modulators, wherein the first modulation frequency in isolation biases the rotation signal at an operating point sensitive to rotation of the optical gyroscope, and wherein the second modulation frequency in isolation biases the rotation signal at an operating point insensitive to rotation of the optical gyroscope; and
one or more control integrated circuits (ICs) to isolate a first portion of the rotation signal associated with the first modulation frequency and a second portion of the rotation signal associated with the second modulation frequency, and further to determine a difference between the first and second portions of the rotation signal to remove one or more bias instabilities from the first portion of the rotation signal.