A Novel Design of a High Integrity Low Cost Navigation Unit for Road Vehicle Applications

Actual solutions for new Intelligent Transport System (ITS) applications cannot fulfill current user requirements. Road applications such as traveller information, route guidance, automatic emergency calls, freight management or electronic fee collection require a road side equipment (RSE) capable to offer a high available accurate position with low price, even in unfriendly environments with low satellite visibility, such as built-up areas or tunnels. Users demand from the RSEs not only accurate continuous positioning, but also integrity information of the reliability of this position. Specifically in life critical applications, high integrity monitored positioning is absolutely required. This paper presents a solution based on the fusion of GNSS and inertial sensors (a GNSS/INS integrated system), running an Extended Kalman Filter combined with an Interactive Multi-Model method (EKF-IMM). The solution developed in this work supplies not only continuous positioning at a reasonable price, but also a meaningful trust level of the given solution.