Low noise fiber gyroscope system which includes excess noise subtraction
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorsRobert P. Moeller, William K. Burns
Life of this patent
Estimating the term…
Abstract
A system and method for subtracting excess noise from a high sensitivity gyroscope system in which a laser diode array is focused into an Nd-doped active fiber. A resultant gyro signal is polarized, detected, and amplified. A noise signal is polarized, delayed, detected, and amplified such that the noise signal is polarized parallel to the gyro signal and delayed by a fiber delay, of a length equal to a length of a gyroscope fiber coil. The excess noise component in the amplified gyro signal is reduced by modulating the amplified noise signal with a portion of the amplified gyro signal and subtracting the amplitude-modulated noise signal from the amplified gyro signal to produce a reduced noise gyro signal.
Claims18
A gyroscope system comprising:
- a fiber gyroscope for detecting and amplifying a gyro signal containing a noise component to produce an amplified gyro signal containing a first noise component;
- fiber delay means, coupled to said fiber gyroscope, for delaying, detecting, and amplifying a noise component of gyro input light to produce an amplified second noise component;
- and
- noise reduction means for reducing the first noise component of the amplified gyro signal by amplitude-modulating the amplified second noise component with the amplified gyro signal to produce an amplitude-modulated noise component and subtracting the amplitude-modulated noise component from the amplified gyro signal to produce a reduced noise gyro signal.
A method of reducing a noise component of a gyro signal from a gyroscope fiber coil of a gyro system, said method comprising the steps of:
- (a) detecting and amplifying the gyro signal from the gyroscope fiber coil to produce an amplified gyro signal containing a noise component;
- (b) delaying, detecting, and amplifying a noise component of gyro input light to produce an amplified noise component;
- and
- (c) amplitude-modulating the amplified noise component with the amplified gyro signal to produce an amplified-modulated noise component;
- and
- (d) subtracting the amplitude-modulated noise component from the amplified gyro signal to produce a reduced noise gyro signal.
Dependencies are inferred from the claim text.