Research on the Technology of Common-View Based on the GEO Positioning System

With the development of science and technology, time and frequency is playing an important role in many fields. Common-view method is one of the main methods for remote precise time and frequency transfer. The method of common-view is characterized by higher precision, good convenience in use, and cheap instrument, so the study on the application of common-view is of great value. A new method to design common-view time transfer system is presented. The system is based on the GEO Positioning System (GEOPS). Different from the other GNSS system, the GEOPS common-view theory is studied based on the GEOPS. This paper introduces the working process and the time service pattern of the GEOPS. In the GEOPS, the pseudo-range tested by the receiver is the actually measurement result of the whole link from the main control station through the satellite to the receiver. Due to the different distances between the main control station and each satellite, measurement has to be done by the main control station by using the upload delay correction. The upload delay adopts a polynomial model and the polynomial parameters demodulated from the navigation message to calculate the delay correction value during the adjustment. In accordance with these characteristics of GEOPS, we proposed the GEOPS common-view time service theory. The parameters format of GEOPS common-view time service and data calculating method are presented. The time synchronization system, the error analysis and the adopted plan by GEOPS common-view time service technology are introduced.