A Method for PPP Reliability Improvement Based on Integrated Multichannel Observations

Due to the implementation of code-division multiple access in global navigation satellite system (GNSS), a receiver can track different channels of observations for the same satellite and frequency. In complex environments, observations from a single channel may be missing during the precise point positioning (PPP) solution process. This article, starting from an exploration of the superiority or inferiority of PPP results using observations from different channels, analyzes the positioning results of the ionosphere-free combined PPP and the undifferenced and uncombined PPP for 42 stations worldwide. It reveals differences in PPP results obtained from different channel observations. Based on this, the article investigates a method for integrating channel observations and compares the PPP results in both static and dynamic environments. In static environments, the positioning accuracy in the East (E), North (N), and Up (U) directions improves by 46%, 29%, and 17% with the ionosphere-free combined PPP model and improves by 39%, 26%, and 25% with the undifferenced and uncombined PPP model. In dynamic environments, the positioning accuracy in the North (N) and Up (U) directions improves by 54.8% and 18.5%, respectively. The statement indicates that the method of integrating channel observations can enhance the accuracy of PPP in complex environments.