Loosely-coupled integration of global navigation satellite system and inertial navigation system: speed scale-factor and heading bias calibration

A system, comprising:

• a global navigation satellite system (“GNSS”) receiver configured to provide GNSS navigation information comprising at least one of a GNSS receiver position estimate and a GNSS receiver velocity estimate;
• an inertial navigation system (“INS”) configured to provide INS navigation information based on an inertial sensor output;
• and
• an integration filter coupled to the GNSS receiver and the INS;
• wherein the integration filter is configured to provide blended navigation information comprising at least one of a blended position estimate and a blended velocity estimate by combining the GNSS navigation information and the INS navigation information, and to estimate and compensate at least one of a speed scale-factor and a heading bias of the INS navigation information;
• wherein the integration filter processes INS velocity from the INS using a measurement equation wherein a plurality of INS measurements in a local navigation coordinate are included in the measurement equation in a way that the INS measurements are a function of position and velocity variables and at least one of speed scale-factor and heading bias variables of an integration filter state with a plurality of measurement noises.