Research of geomagnetic effect on FOG north-finder

In this paper, the principle of FOG north-finder is introduced briefly, geomagnetic effect on FOG north-finder is pointed out and existence of magnetic sensitivity axis is analyzed theoretically and validated by experiments. Reasons of FOG sensitivity on geomagnetism and relations between FOG output and magnetic sensitivity are analyzed in detail. Finally, improved methods are put forward from the aspects of FOG produce process, assembly methods and software arithmetic of FOG north-finder. It is obvious that geomagnetic sensitivity of FOG is reduced effectively and thus further improved precision of FOG north-finder.