Research On Accuracy And Integrity Airworthiness Technology For Beidou GBAS Airborne PAN Equipment

As an important choice for the next generation of satellite navigation landing system,the Ground-Based Augmentation System(GBAS)can make up for many inherent shortcomings of traditional landing systems and provide users with higher standards of required navigation performance(RNP).The prerequisite for the promotion and popularization of GBAS in civil aviation is the establishment and improvement of airworthiness standards.However,there are relatively few studies on Beidou GBAS airworthiness testing in China,and there is no corresponding standard document and unified testing method.In this thesis,the accuracy and integrity airworthiness testing technology applicable to the Beidou GBAS airborne Position and Navigation(PAN)equipment are researched by referring to the test requirements for accuracy and integrity of GBAS airborne PAN equipment in the Technical Standard Oder TSO-C161 a and the Standard document RTCA DO-253 D.The main contents are as follows:First of all,based on the brief introduction to the overall structure and working principle of GBAS,the working principle and basic algorithm of GBAS airborne subsystem and ground subsystem are explained in detail.At the same time,the airworthiness compliance verification method of airborne PAN equipment is studied.And according to the research focus of this thesis,the recommended verification method is given.Secondly,According to the requirements for accuracy in RTCA DO-253 D,the accuracy-related parameters of the airborne PAN equipment were studied,the specific test methods and procedures were given,and the experiments were carried out for simulation verification.These include pseudorange accuracy,position accuracy and position figure of merit,velocity accuracy and velocity figure of merit.Then,according to the integrity risk allocation requirements of GBAS approach service and position service in RTCA DO-245 A,combined with the error model of airborne equipment given in DO-253 D,the integrity of the airborne PAN equipment is studied,and the specific test methods and test plans were given.These include the protection levels and ephemeris error position bounds in approach service and position service.Finally,aiming at the relevant content of the precision approach guidance outputs of the airborne PAN equipment given in TSO-C161 a,based on the in-depth analysis of the MT4 data format and the content of the FAS data block,the deviation in the precision approach guidance output is studied,and combined with relevant standard documents the theoretical thresholds for deviations was given.Subsequently,the alarm content and trigger conditions in the precision approach guidance outputs were introduced,and the correctness of the thresholds above was verified through the bias approach monitor(BAM)evaluations.