Research On The Influence Of Group Delay Characteristics Of High Precision Navigation Receiver On Distance Measurement Performance

High precision navigation receiver is the core measurement equipment of satellite navigation system and the basis for navigation system to provide high-performance services.The high-precision military reference station has the demand for miniaturization of the navigation receiver in the station,which makes the positioning performance of the navigation receiver unable to be guaranteed.In view of the above background,through the high-precision measurement of the group delay characteristics of the actual high-precision receiver channel,based on the actual group delay measurement results,this paper explores the impact of the group delay characteristics of the high-precision navigation receiver on the ranging performance,and puts forward a newly defined RF design group delay characteristic index,to provide reference and support for the miniaturization design of receiver under high-precision ranging performance.The main contents and achievements of this paper are as follows:(1)The related theoretical model of the influence of group delay characteristics on the ranging performance is introduced in detail,which provides a theoretical basis for the simulation and actual measurement analysis later.In the theoretical model of the navigation receiver group delay characteristics,it focuses on the definition of group delay and the navigation receiver group delay characteristics;in the theoretical model using the software receiver to evaluate the ranging performance,it focuses on the signals in its composition architecture.Generation principle,channel characteristic simulation principle and ranging performance evaluation method,as well as the concept of code phase and carrier phase.(2)A method for measuring group delay characteristics based on the carrier phase of frequency division multiple access signals is proposed,which provides a basis for high-precision group delay measurement for subject research.The group delay characteristic is used to meet the prior conditions of the segmented parabolic characteristic,and the group delay characteristic’s whole-period ambiguity is fixed by traversing the parabolic coefficient and the whole-period ambiguity,so as to realize the accurate measurement of the group delay characteristic.The simulation shows that the measurement accuracy only depends on the measurement error of the carrier phase,which can reach the order of picoseconds,and it can take into account the measurement accuracy and the measurement resolution.(3)The group delay modeling method based on shape characteristics is proposed,which provides a model basis for exploring the influence of group delay characteristics on the ranging performance.Taking the group delay characteristic measurement results of multiple sets of actual receivers as a reference,the group delay characteristic shape characteristics such as fluctuation range,extreme value inconsistency and duty cycle inconsistency are extracted,and the group delay characteristic based on the segmented parabola model is established based on this Mathematical analysis model.By exploring the influence of shape characteristics on the delay deviation,and analyzing the influence function model of shape characteristics on the delay estimation error,a newly defined navigation receiver channel design group delay characteristic index is proposed from the perspective of shape characteristics to guide the actual channel design.Finally,the research content is summarized,and the next work is prospected.