Adjustable-precision time acquisition method based on second pulses

Abstract

The invention provides an adjustable-precision time acquisition method based on second pulses. The method includes: receiving UTC time information, which is issued by a GPS receiver, by a PPC processor, and obtaining hour, minute and second data, which are synchronized with a GPS, after solution calculation; generating precision information by the PPC processor, and passing the hour, minute, second and less-than-second data obtained after solution calculation and the precision information to an FPGA clock acquisition unit; receiving a local clock signal from a local clock source by the FPGA clock acquisition unit, receiving a PPS signal from the GPS receiver, and calibrating the received hour, minute, second and less-than-second data; and sending back the calibrated hour, minute, second and less-than-second data to the PPC processor by the FPGA clock acquisition unit through an LBC bus to realize calibration of less-than-second data. According to the method, time precision configuringis flexible, and time acquisition precision is high.

Description

technical field [0001] The invention relates to the technical field of clock synchronization of aviation equipment systems, in particular to a method for acquiring time with adjustable precision based on second pulses. Background technique [0002] System time synchronization between aviation airborne equipment is particularly important, and system time synchronization is the basis for ensuring normal communication and collaborative work between equipment. In the whole system, the device terminal can obtain a high-precision clock by receiving GPS signals or B codes, and use this clock as a reference to serve time to other devices. Although the accuracy of the UTC time frame output by the terminal in RS422 format can reach 1us or even higher, due to the serial-to-parallel conversion delay inside the terminal, the transmission delay of the data line, and the serial-to-parallel conversion delay of the time-service device, the time-service device can obtain The UTC time is not ...

AI Technical Summary

Problems solved by technology

However, this technology has the problem of being unable to flexibly adjust the precision of the clock below the second

In this technology, FPGA designers set a fixed clock accuracy of less than one second according to the actual use requirements of the timing equipment, and the accuracy cannot be adjusted during use.

When the time service equipment needs to use higher precision time due to changes in requirements, FPGA designers need to redesign the logic circuit according to the new requirements, which brings great inconvenience to the upgrade and expansion of the time service equipment functions

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