Earth reference thin-film magnetometer compass exhibiting total tilt immunity

A thin-film magnetometer compass apparatus having total tilt immunity comprising in combination:

• a plurality of thin-film magnetometer sensors arranged on a platform coordinate system in orthogonal relationship to each other, said plurality of thin-film magnetometer sensors are rigidly mounted with respect to said platform coordinate system, each of said plurality of thin-film magnetometers receiving an input signal, each of said plurality of thin-film magnetometer sensors providing an output signal respectively, said output signals having a varying amplitude, said amplitude varying as a function of the magnitude of the earth's magnetic field, and
• means for computing the north vectors receiving each of said output signals and said input signal, said computing means processing said output signals with respect to each other and with respect to said input signal to define platform angular deviation, said computing means providing a first and second DC voltage representing said platform angular deviation, said computing means comparing said first and second DC voltage with magnetic and true north reference voltages to provide the angular deviations with respect to magnetic and true north respectively.