Magnetic field perturbation compensating system for aircraft - analyses development of modulus of earth field perturbed in space to transform ellipsoidal theoretical sphere

摘要

The device contains a magnetometer which give electrical signals proportional to the components of the perturbed magnetic field. A processor calculates directly the coefficients used to correct the data delivered by the magnetometer without needing to compare with a known head. The earth's field modulus is considered as constant between two successive measurements. The evolution of this modulus perturbed in the space is observed. The compensation coefficients, iteratively calculated, permit the evaluation of this modulus to be converted from an ellipsoid to a theoretical sphere centered on the magnetometer axis in order to define the correspondence between the perturbed measurements and the real measurements. The tensor expressing the induced fields in considered symmetric.