A Method and Structure for Determining the Global Clock Between Systems

Abstract

A method and structure for determining a global clock between systems. When a unified time reference is required between systems, the reference clock source sends out a calibration signal and records the sending time Td(0). After each system receives the calibration signal, it records the arrival time Ta(n ), and at the same time each sends a return signal to the signal recording unit of the reference clock source and records the sending time Tb(n). Also due to the different distances, the signal recording unit sequentially records the arrival time Td(n) of the return signal, then it is determined that the system and the reference clock The time delay Delay(n) of the source, when all systems are required to have a completely unified time reference, the corresponding Delay(n) will be obtained and sent to each system, and each system determines the zero point deviation between various local clocks and the reference clock source Tc(n), using Tc(n) as a correction parameter to correct its own system clock, so that the local clocks of all systems have completely consistent clock references.

Description

technical field [0001] The invention belongs to the technical field of time test and measurement, and relates to a method for determining a reference time, in particular to a method for determining a global time. Background technique [0002] The global clock can be applied in many fields. Only when the global clock is synchronized between independent systems, so that the clocks of each independent system reach a consistent clock reference, can the collaborative work of the array be completed and consistent measurement conditions be guaranteed between systems. Therefore, it is necessary to provide a method for determining the global clock between systems. [0003] The existing inter-system global clock determination often adopts the method of time stamp communication between multiple systems to obtain the timing reference of each clock and then further calibrate it. This method is widely used in the communication field, although it can realize system Time synchronization be...

AI Technical Summary

Problems solved by technology

[0003] The existing inter-system global clock determination often adopts the method of time stamp communication between multiple systems to obtain the timing reference of each clock and then further calibrate it. This method is widely used in the communication field, although it can realize system Time synchronization between time, but this synchronization method is limited to the use of ready-made communication protocols (time reference can be packaged into time stamps) to achieve global clock synchronization with low precision, such as ms or sub-ms or us or sub-us level, this kind of The accuracy of the method ultimately depends on the speed of the clock, that is, the flip frequency, and will not achieve synchronization accuracy shorter than the clock period

In fields such as nuclear detection and time-of-flight applications, multiple independent systems often require completely consistent time references to meet precise time measurement. The fully synchronized global time requires very high accuracy, reaching the ns to ps level, often The clock cycle of the system clock is smaller than the clock period of the system clock. The layout of the global clock needs to consider the subtle differences of the respective clocks between the systems due to the different power-on sequences, so the traditional method cannot meet the requirements.

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