The Research On Modeling Of Phase Center Of GPS/BDS Navigtion Antenna

With the continuous development of satellite positioning technology, it plays an increasingly important role in military and commercial fields, which puts forward higher requirements for the accuracy of satellite positioning, but the antenna phase center error is an important factor restricting its accuracy. Establishing a GPS/BDS antenna phase center model not only improves the accuracy of positioning, but also combines GPS with BDS so as to get rid of the dependence on foreign satellite navigation system.This paper focus on the design of a GPS/BDS antenna phase center correction model. This paper obtains the GPS/BDS antenna phase offset by combining the rotating antenna method and the horizontal antenna method, and obtains the GPS/BDS antenna phase variation through the outdoor relative determination, and a set of GPS/BDS antenna phase center model is established.According to the proposed design, the outside SSBL relative measurement is carried out to obtain the data of the GPS/BDS antenna phase center correction model,and get PCO and PCV for GPS signal L1 and signal L2. Compared with the reference value in the microwave Microwave anechoic chamber, the PCO error of the antenna phase center correction model in this paper is about 0.87mm, the PCV error increases with the increase of the elevation angle and the maximum error is 2.34 mm,so the error of the Model is millimeter. The difference between the baseline vector calculated after adding the correction model and the reference model is less than 0.5 mm, and it is sub-millimeter. These obtained results prove that the accuracy of test results reached a certain level, which proving the design of the program can improve the positioning accuracy. Then we obtained the antenna PCV under different states according to the design scheme, and find that the choke can weaken the influence of multipath effect when the antenna is placed horizontally.