Gyro aided magnetic compass

A method comprising:

• sensing a heading of a body based on earth's magnetic field;
• providing an initial heading based on the sensed heading;
• sensing angular motion of the body with an angular rate sensor;
• providing an angular rate signal based on the sensed angular motion;
• integrating the angular rate signal to provide a second heading signal;
• generating a hybrid heading signal based on the initial heading and the second heading signal;
• providing a first heading signal based on the sensed heading;
• and
• blending in the first heading signal with the hybrid heading signal at an adaptive time interval, wherein said adaptive time interval varies based upon the presence of magnetic compass errors as determined by a processing unit.

A gyroscope-aided compass comprising:

• geomagnetic sensing means for sensing a heading and providing a corresponding first heading signal;
• angular velocity sensing means for sensing motion and outputting a corresponding angular velocity signal;
• signal integrating means communicatively coupled to the angular velocity sensing means to receive the angular velocity signal and output a second heading signal;
• and
• a processing means communicatively coupled to the geomagnetic sensing means and signal integrating means, the processing means configured to
• receive an initial reference heading from the geomagnetic sensing means,
• generate a hybrid heading signal based on the initial reference heading and the second heading signal, and
• blend the first heading signal with the hybrid heading signal at an adaptive time interval, wherein said adaptive time interval varies based upon the presence of magnetic compass errors as determined by said processing means.