Signal conditioning to provide optimum gain and noise reduction for resonator fiber optic gyroscopes

A signal-conditioning circuit implementable in a resonator fiber optic gyroscope (RFOG), the RFOG including a first light source configured to generate a first light signal, a resonator element configured to generate a first optical signal based on the first light signal, a first photodetector configured to generate a first electrical signal based on the first optical signal, the first electrical signal including an oscillating signal, a first direct-current (DC) signal, a first even-harmonic signal comprising components at even harmonics of the oscillating signal, and a first odd-harmonic signal comprising components at odd harmonics of the oscillating signal, and a first analog-to-digital converter (ADC), the circuit comprising:

• a first filtering element configured to be coupled to the first photodetector and configured to attenuate the first DC signal, at least one even-harmonic component of the first even-harmonic signal, and a first odd-harmonic component of the first odd-harmonic signal to produce a second electrical signal;
• and
• a first amplifier coupled to the filtering element and configured to amplify the second electrical signal, wherein the first ADC is configured to digitize the amplified second electrical signal.