Improved Inertial Navigation With Cold Atom Interferometry

This article discusses chances and challenges of using cold atom interferometers in inertial navigation. The error characteristics of the novel sensor are presented, as well as one option for an online estimation of the different readout errors. An extended Kalman filter framework is derived and analysed which uses the readout of the atom interferometer as observation in order to correct several systematic errors of a conventional IMU, allowing for an improved strapdown calculation in an arbitrary target system. The performance gain is discussed analytically based on the steady state variances of the filter, as well as on the example of a simulated scenario for Earth orbit satellites. The correction of the conventional IMU errors is further demonstrated in an experiment under laboratory conditions with a higher class sensor emulating an atom interferometer. While the application of the novel technology as a gyroscope is still limited, as pointed out in the paper, the presented framework yields options for a full six degree of freedom operation of the atom interferometer.