Inertia-assisted multi-frequency multi-mode GNSS cycle slip repair method and system

Abstract

The invention provides an inertia-assisted multi-frequency multi-mode GNSS cycle slip repair method and system. The method comprises the steps that cycle-slip observation is conducted on all satellites to judge the satellites with the existence of cycle slip; after cycle-slip parameters are determined, a pseudo space and phase position non-difference uncombined epoch difference observation equation on frequencies and systems is formed, and a clock difference variation parameter is introduced; according to the activity degree of an ionosphere layer, fitting functions with different orders in a sliding window are used to model and forecast the time-varying ionosphere layer; inertia-assisted cycle slip calculation is conducted, and posteriori residuals of the cycle slip repair equation are tested; a three-step method is used to fix cycle slip values and carry out the cycle slip repair, and finally phase position observation values are repaired. The inertia-assisted multi-frequency multi-mode GNSS cycle slip repair method and system can accurately repair cycle slip values on different frequencies of different GNSS systems in a dynamic and complicated environment, and provide clean and pollution-free observation data for subsequent positioning and calculating treatments.

Description

technical field [0001] The invention belongs to the field of GNSS / SINS integrated navigation, in particular to an inertial-assisted multi-frequency and multi-mode GNSS cycle slip repair method and system. Background technique [0002] Global Navigation Satellite System (GNSS, Global Navigation Satellite System) has entered a new era of multi-frequency and multi-mode, and the four major systems represented by GPS, GLONASS, BDS and Galileo are developing steadily. Up to now, GPS has 10 satellites capable of transmitting L5 frequency signals, GLONASS next-generation satellite GLONASS-K will also be able to transmit third-generation frequency signals, BDS satellites in orbit include 14 Beidou 2nd generation satellites and 5 Beidou 3rd generation satellites, All satellites are capable of transmitting tri-frequency signals, while 11 Galileo satellites in orbit can work normally, and all satellites can transmit multi-frequency signals. Multi-frequency and multi-mode GNSS increases...

AI Technical Summary

Problems solved by technology

[0004] 1) Under different ionospheric conditions, the observations of different systems and frequencies need to select different ultra-wide lane-wide lane-narrow lane combinations. As the types of observation values ​​increase, more complex combination pairs will be formed. Facilitate unified processing of cycle slip repair

[0005] 2) A combination method is used to repair the cycle slip step by step. If a certain combination cannot successfully repair the cycle slip, then the cycle slip repair on all frequencies will fail, and the narrow lanes in this combination method are affected by various errors. Fixing is equally difficult

[0006] 3) The current cycle slip repair technology only uses the observation information of GNSS itself. With the widening of GNSS application fields, complex environments such as urban canyons, high dynamic conditions, and signal interference appear. The number of satellites is less than 4, and the quality of observations is not good. , will seriously affect the success rate of cycle slip repair

[0007] 4) The LAMBDA method is used to fix the integer value of the cycle slip. Although the reliability is good, it is affected by various errors, the fixed rate is relatively low overall, and the cycle slip repair is prone to failure.

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