Performance improvement of integrated MEMS/GNSS systems

Abstract

Inertial Navigation Systems (INS) and Global Navigation Satellite Systems (GNSS) are often combined in vehicle navigation systems to ensure high accuracy navigation. The last generation of Inertial Measurement Unit (IMU) referred to as Micro-Electro-Mechanical Systems (MEMS) might be used in a lot of new applications thanks to their relatively low cost. Unfortunately, the information given by the MEMS are less accurate than with classical INS. This paper studies a two-step inversion procedure which improves the performance of an integrated GNSS/MEMS navigation system. This inversion is based on a good knowledge of the non linear model of the sensor output.