Resonant optical gyroscope with integrated optical components and a broadband optical source

A method of generating at least one signal configured to be used to determine a rate of rotation, the method comprising:

• generating, in a photonic integrated circuit (PIC), an amplified spontaneous emission;
• dividing, in the PIC, the amplified spontaneous emission into a first portion and a second portion;
• phase modulating, in the PIC, the first portion with an in-phase periodic signal;
• phase modulating, in the PIC, the second portion with a phase inverted periodic signal;
• receiving, in the PIC, a first phase modulated portion, of the amplified spontaneous emission, at a first port of an optical resonator;
• receiving, in the PIC, a second phase modulated portion, of the amplified spontaneous emission, at a second port of the optical resonator;
• emitting, in the PIC, a first resonant optical signal from the second port of the optical resonator, wherein the first resonant optical signal circulates around the optical resonator in a first direction;
• emitting, in the PIC, a second resonant optical signal from the first port of the optical resonator, wherein the second resonant optical signal circulates around the optical resonator in a second direction which is opposite to the first direction;
• combining in the PIC, the first and the second resonant optical signals.

A resonant optical gyroscope, comprising:

• a photonic integrated circuit (PIC) including a substrate, wherein the PIC includes:
• a broadband optical signal source optical circuit configured to generate an amplified spontaneous emission;
• an optical divider/combiner;
• a first optical coupler or circulator optically coupled between the broadband optical signal source optical circuit and the optical divider/combiner;
• wherein the first optical coupler or is configured to receive the amplified spontaneous emission and to emit the amplified spontaneous emission to the optical divider/combiner;
• wherein the optical divider/combiner is configured to emit a first portion and a second portion of the amplified spontaneous emission;
• a first optical phase modulator optically coupled to the optical divider/combiner, and configured to phase modulate the first portion of the amplified spontaneous emission with an in-phase periodic signal;
• a second optical phase modulator optically coupled to the optical divider/combiner and configured to phase modulate the second portion of the amplified spontaneous emission with a phase inverted periodic signal;
• and
• an optical resonator including a rotation axis and optically coupled to the first and the second optical phase modulators;
• wherein the optical resonator is configured to (a) receive a first phase modulated portion of the amplified spontaneous emission from the first optical phase modulator, (b) receive a second phase modulated portion of the amplified spontaneous emission from the second optical phase modulator, (c) emit a first resonant optical signal, and (d) emit a second resonant optical signal;
• wherein the optical divider/combiner is further configured to combine the first and the second resonant optical signals;
• an optical detector optically coupled to the first optical coupler and configured to receive a combined first and second resonant optical signals;
• a periodic signal generator configured to generate the in-phase periodic signal, the phase inverted periodic signal, and a reference periodic signal;
• a demodulating circuit electrically coupled to the optical detector and configured to (a) receive the reference periodic signal or the phase inverted periodic signal and (b) emit a demodulated electrical signal;
• and
• circuitry configured to, using the demodulated electrical signal, determine a rate of rotation of the optical resonator around rotation axis;
• wherein the broadband optical signal source optical circuit configured to generate the amplified spontaneous emission includes:
• a laser configured to emit a pump optical signal;
• a planar optical waveguide configured to receive the pump optical signal and generate the amplified spontaneous emission;
• and
• a wavelength division multiplexor configured to optically couple the pump optical signal to the planar optical waveguide configured to generate the amplified spontaneous emission, to receive the amplified spontaneous emission from the planar optical waveguide configured to generate the amplified spontaneous emission, and to optically couple the amplified spontaneous emission to the first optical coupler or circulator;
• wherein the wavelength division multiplexor is further configured to suppress the amplified spontaneous emission coupled to the laser and to suppress the pump optical signal coupled to the first optical coupler or circulator;
• wherein the pump optical signal has a narrower line width than a bandwidth of the amplified spontaneous emission.