Assisted adaptive extended Kalman filter for low-cost single-frequency GPS/SBAS kinematic positioning

作者：Lin Shiou Gwo^*

来源：GPS Solutions, 2015, 19(2): 215-223.

DOI：10.1007/s10291-014-0381-9

• GPS
• SBAS
• Adaptive extended Kalman filter
• Kinematic positioning

Using a low-cost single-frequency global positioning system (GPS) receiver for kinematic positioning, the ambiguity resolution requires longer data accumulation time compared to survey-grade dual-frequency receivers. A satellite-based augmentation system (SBAS) can provide added measurement to help solve this problem. However, the SBAS signal strength is weaker and the satellite orbit and clock errors are greater than those of GPS satellites. The difference in phase measurement quality between GPS and SBAS satellites must be considered to prevent an unstable positioning result or diverging position solution. This study proposes using the assisted adaptive extended Kalman filter (AAEKF) method to address this problem. The concept of AAEKF involves using measurements from the reference station to estimate the errors of each satellite. This information is then employed to dynamically adjust the corresponding measurement model of the extended Kalman filter. The proposed method was validated with 24 h of experiment data from four different baselines obtained using a consumer-grade L1 GPS receiver. The experimental results show that AAEKF can be successfully employed for GPS/SBAS kinematic positioning. The ambiguity resolution success rates of 2, 5, and 10 min of measurements improved by about 3.2, 2.4, and 1.6 times, respectively, and the positioning accuracy of the north, east, and height directions improved by 14-44, 17-56, and 9-53 %, when adding the SBAS measurement.

• 出版日期2015-4