System and method for testing satellite-ground time delay and onboard time errors

Abstract

The invention discloses a system and method for testing satellite-ground time delay and onboard time errors. The method comprises the steps of: firstly, acquiring format pulses generated based on onboard telemetering, and recording GPS (Global Position System) time generated by the format pulses; and then, demodulating to generate telemetering format pulses by using a special testing device and recording the GPS time for demodulating the format pulses. The satellite-ground time delay can be calculated by means of two telemetering format pulses read by an oscilloscope, and can also be acquired by calculating a difference between two GPS time through a program. A 1553B bus monitoring module is used for monitoring air time codes of a center computer of a satellite on a bus, a GPS data receiving processing module is used for acquiring ground GPS time, and a master control module is used for calculating difference values between the air time codes and the ground GPS time so as to acquire the onboard time errors. The satellite-ground time delay measurement precision is not less than 200us, and the onboard time measurement precision is not less than 100us.

Description

technical field [0001] The invention relates to a satellite-ground time service testing method and system, which are mainly used for satellite system-level tests and for testing satellite-ground time delay and satellite time error. Background technique [0002] A certain type of communication satellite is equipped with a high-stable clock source, which is used as the clock source for satellite timing. According to the preset time interval, the on-board time is broadcast to the payload device through the 1553B bus, and the on-board time is downloaded through the telemetry channel. In order to meet the requirements of accurate data interception and real-time information transmission, the satellite is designed with the function of satellite-ground time service, that is, to correct the on-board clock when the error of the on-board time exceeds the specified range. [0003] After the satellite leaves the factory, the accuracy of the on-board clock needs to be tested during the gr...

AI Technical Summary

Problems solved by technology

The above method ignores the time loss from satellite telemetry generation to transmission, and realizes the satellite-ground delay measurement of the telemetry channel during the satellite comprehensive test. There are two problems: 1. The test accuracy is not enough, and the error is at the ms level; 2. Only the ground is measured The time delay of equipment telemetry reception demodulation cannot test the delay of satellite telemetry signal modulation and radio frequency link

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