Absolute calibration of timing receiver based on clock-steering model

作者：Zhu Feng^*; Li Xiaohui; Zhang Huijun

来源：Chinese Journal of Scientific Instrument, 2014, 35(9): 1946-1954.

• Absolute calibration
• Combined uncertainty
• Hardware simulators
• Pseudo range
• Pseudorange measurements
• Satellite navigation
• Steering performance
• Time-to-code (TtC)

Delay calibration of timing receiver is always a difficult point in satellite navigation, and the calibration methods for different types of receivers are also different, which should be studied with pertinence solutions. On the basis of analyzing the timing receivers without external 1PPS input, the paper studies an absolute calibration method of receiver delay based on clock-steering model. Compared with the receiver with external 1PPS input used by NRL, the receiver delay based on clock-steering model is not only affected by pseudorange measurement and hardware link delay, but also related to the resolution of system clock;thus higher clock resolution leads to better steering performance of the receiver, which corresponds to lower channel delay. Spirent GSS8000 was chosen as the GNSS hardware simulator to absolutely calibrate the receivers of Novatel and Septentrio in the experiment. Affected by tracking loop and RF filter group delay, the delays of various receivers for different frequency bands and PRN codes are different. The uncertainty of Novatel receiver for C/A code is 1.2 ns, which is better than the 1.5 ns for P code;and the uncertainty of Septentrio receiver in L1-band is 1.5 ns, which is higher than the 1.3 ns in L2-band. However, due to the instability of the system clock, the ionosphere-free combined uncertainty of Septentrio is 4.3 ns, which is higher than the 3.8 ns of Novatel receiver.

• 出版日期2014
• 单位中国科学院大学