Research on the Selection Method of Triple Frequency Combination Based on the Beidou Satellite Navigation System

Abstract

With the application of Chinese Beidou satellite navigation system more and more widely, its existing navigation accuracy and timeliness can not meet the requirements for use, how to improve the accuracy of the Beidou satellite navigation and positioning has gradually become a new hotspot. Existing main methods to improve navigation accuracy and timeliness are repair cycle slip, smooth pseudorange residuals and other methods, but they can only improve a single aspect of the error, can not simultaneously weaken the influence of multiple errors. However, triple frequency combination navigation can speed up the determination of integer ambiguity, weaken the ionospheric delay, reduce the observation noise, improve the precision of positioning effect is obvious. By a brief introduction of Beidou satellite navigation system to study conducted three frequency carrier phase combination method based on three frequencies have been published. While maintaining the ambiguity is an integer of the premise, by analyzing the ionospheric delay, observation noise and other factors affect on triple frequency combinations observations, based on the long-wavelength combination standard, weak ionospheric delay combination standard and weak observation noise combination standard, obtained a linear combination of good performance, effectively improve the navigation and positioning accuracy and timeliness. The results showed that: a combination of (1, 4, −5) and other combinations of observations can have longer wavelength while effectively weaken the ionospheric delay effects, significantly reduces the ambiguity initialization time, has certain reference value for the future development of the Beidou satellite navigation system.