Abstract
This study proposes two models for precise time transfer using the BeiDou Navigation Satellite System triple-frequency signals: ionosphere-free (IF) combined precise point positioning (PPP) model with two dual-frequency combinations (IF-PPP1) and ionosphere-free combined PPP model with a single triple-frequency combination (IF-PPP2). A dataset with a short baseline (with a common external time frequency) and a long baseline are used for performance assessments. The results show that IF-PPP1 and IF-PPP2 models can both be used for precise time transfer using BeiDou Navigation Satellite System (BDS) triple-frequency signals, and the accuracy and stability of time transfer is the same in both cases, except for a constant system bias caused by the hardware delay of different frequencies, which can be removed by the parameter estimation and prediction with long time datasets or by a priori calibration.
Highlights
Precise time is critical for military strikes, as well as for national infrastructure facilities, such as electric power supply, banks, and communication networks [1]
The results shown that IF-PPP1 and IF-PPP2 models can both be used for precise time transfer using BeiDou Navigation Satellite System (BDS) triple-frequency signals, and the accuracy and stability of time transfer is the same in both cases
The code biases caused by the inter frequency bias (IFB) parameter should be introduced in the IF-PPP1 model to compensate for the different effects on different frequency bands, and for the IF-PPP2 model, it can be absorbed by the receiver clock parameter and cause system bias in precise time transfer
Summary
Precise time is critical for military strikes, as well as for national infrastructure facilities, such as electric power supply, banks, and communication networks [1]. Time transfer can be performed using BPM/BPL (ground-based radio stations that broadcast short-wave and long-wave time signals, respectively), two-way satellite time and frequency transfer (TWSTFT), optical fiber (OP), and global navigation satellite system (GNSS) [1]. The main contribution of this study is that it proposes two models for precise time transfer by using BDS triple-frequency signals: ionosphere-free (IF) combined precise point positioning model with a single triple-frequency combination (IF-PPP2) It evaluates the performance of these models for BDS time transfer. The constant system bias caused by the hardware delay of different frequencies is stable and can be removed by the parameter estimation and prediction with long time datasets or by a priori calibration These models and validation results will be important for the BDS precise time transfer.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
