High-precision GPS (global position system) distributive time-service method based on ping-pong buffer and message mechanism

Abstract

The invention provides a high-precision GPS (global position system) distributive time-service method based on ping-pong buffer and a message mechanism. Clock synchronization among special equipment in a space remote control system is realized by a precise clock synchronization policy of hardware on time; and a GPS satellite synchronous clock serves as a clock source, and the time of each piece of special equipment is checked periodically by second pulse. Time information processing operation is completely finished in an FPGA (Field Programmable Gate Array), so that the time synchronization precision of the special equipment is not affected and the normal work of application programs of the special equipment is not intervened. A time-service time source also supports an IRIG-B (Inter Range Instrumentation Group) code time service, wherein the time frame speed of an IRIG-B type code is 1 frame / second, and 100-bit information can be transmitted. After a B type code is decoded, a 1c / s pulse signal, a 10c / s pulse signal, a 100c / s pulse signal. a 1,000c / s pulse signal, BCD (Binary-Coded Decimal) encoding time information and control function information can be acquired, and the synchronization precision can be up to dozens of nanosecond.

Description

technical field [0001] The invention belongs to a GPS distributed timing system, in particular to a high-precision GPS distributed timing method based on a ping-pong buffer and a message mechanism, in particular to a read-write buffer control mechanism based on a ping-pong buffer and a message notification. Background technique [0002] The space teleoperation system is composed of multiple units distributed in different computers. In order to ensure the cooperation between the teleoperation system and the operation object system, to ensure the consistency and continuity of teleoperation instructions, and to measure the time delay and The size and its change, the time synchronization accuracy between each link needs to reach 1ms. Using the traditional network timing technology (NTP, Network Time Protocol), its time accuracy is 10ms in the local area network, and about 1s in the wide area network, which is far from meeting the requirements of delay measurement accuracy and ti...

AI Technical Summary

Problems solved by technology

Synchronization accuracy is affected by network load and CPU load, and there is also the problem of bit error rate in network transmission, and frequent clock drift compensation is required, which will increase CPU usage

It is also possible to use a mixed method of software and hardware to achieve clock synchronization. The algorithm shows that this method occupies more network bandwidth.

If the clock synchronization method is realized by FPGA, because it involves Ethernet, it is necessary to solve the problem of time conflict between network communication and the work of the timed equipment; because this method still uses the Windows operating system as the control core of both parties, it will affect the timing of the timed device. The normal operation of the time service equipment, and other factors such as system response time delay will also affect the final time synchronization accuracy of the time service equipment

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