High Precision Clock Synchronization for Distributed Full Trajectory Test of Light Weapon Ballistic Range

In the clock synchronization of distributed full trajectory test of light weapon ballistic range, the accuracy of clock synchronization decreased with the increase of nodes, the extension of communication path and the aging and temperature drift of crystal oscillator, and the stability deteriorated. In order to achieve the synchronization accuracy of ±300 ns of the distributed clock network in the ballistic range, in the basis of analyzing the implementation principle of IEEE1588 protocol, the error caused by the crystal oscillator was analyzed, and the temperature compensated crystal oscillator was used to suppress the temperature drift, at the same time, the switch with PTP protocol was used to interact with the master-slave clock and the transparent clock was used to calculate the dwell time. In the distributed network system with two different structures of hierarchical topology and linear topology, considering the problems encountered in the system operation, the anti-interference performance of the system was improved by using amplitude limiting average filtering, and the fluctuation reasons of clock synchronization results was explored and verified. The synchronization accuracy was improved from ±300 ns to ±30 ns. The experimental results show that the synchronization accuracy of master-slave can be stabilized at ±120 ns for a long time in the case of two stage switches, and can be stabilized at ±30 ns in the optimal case, and the system has strong anti-interference capability, so it can meet the accuracy level required for target channel testing.