DGPS/INS-based vehicle positioning with novel DGPS noise processing

The vehicle positioning system is a key component in such functions as vehicle guidance, driver alert and assistance, as well as vehicle automation. Typical vehicle applications require high reliability, low cost and sufficient accuracy under all operation conditions. This paper explores the feasibility of a low-order vehicle positioning system functioning under urban driving environments. The equipped vehicle will have a mid-range differential GPS (DGPS) unit and a few relatively simple in-vehicle sensors. A low-order DGPS/INS integration is explored by considering only vehicle longitudinal, lateral and yaw motions. The characteristics of DGPS measurements under urban environment are investigated and novel DGPS noise processing techniques are proposed to address common DGPS problems such as blockage and multipath. A resulting 4(th)-order Kalman filter-based DGPS/INS integration is successfully implemented in the test vehicle to demonstrate the feasibility of the proposed design. Experimental results illustrate the ability of the system to meet the accuracy and robustness requirements under a typical urban driving environment.