Doppler aided inertial navigation
AssigneeTeleCommunications Systems, Inc.
InventorsMichael B. Mathews, Peter F. MacDoran
Life of this patent
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Abstract
Doppler Aided Inertial Navigation (DAIN) facilitates the determination of position, velocity and direction of mobile devices operating in highly obstructed GPS/GNSS environments. Delivering high precision, high resolution positioning information using signals of opportunity, the present invention measures the Doppler shift of a moving device using a variety of signals combined with inertial accelerometers and environmental sensors to deliver an autonomous positioning and navigation capability that does not require external infrastructure or a priori knowledge of signal sources.
Claims17
A mobile computing device comprising:
- a receiver that transforms two or fewer intercepted radio frequency emissions external to the mobile computing device into Doppler frequency observables;
- a plurality of inertial sensors, each sensor having a linear accelerometer that produces acceleration observables;
- a spectral compression positioning sensor that performs spectral compression utilizing a non-linear operation on the Doppler frequency observables to produce a set of Doppler frequency observables in a format for physical state estimation by the physical state estimator;
- and
- a physical state estimator that:
- processes the set of Doppler frequency observables and the acceleration observables to determine a member of a physical state of the mobile computing device;
- converts Doppler frequency observables to speed;
- and
- corrects inertial drift error of the plurality of inertial sensors based on the speed.
A method comprising:
- intercepting, at a RF Doppler Receiver, two or fewer radio frequency emissions external to a mobile computing device;
- transforming, at a spectral compression positioning sensor, by spectral compression utilizing a non-linear operation, the Doppler frequency observables from the two or fewer intercepted radio frequency emissions into a set of Doppler frequency observables for physical state estimation;
- receiving, at a physical state estimator, acceleration observables from a linear accelerometer from a plurality of inertial sensors associated with the mobile computing device;
- processing, at the physical state estimator, the set of Doppler frequency observables and received acceleration observables to determine a member of a physical state of the mobile computing device;
- determining, at a narrowband signal detector, speed of the mobile computing device from the Doppler frequency observables;
- and
- correcting, at the physical state estimator, inertial drift error based on the speed.
Dependencies are inferred from the claim text.