Development Of Muti-channel High-precise Time-stamp Device

Time stamp is to determine the time information of a pulse signal occurrence or end.With the improvement of socio-economic level and the development of science andtechnology, multi-channel high-precision time stamp shows its important role, in many areasof communication, timing, electronic trading, electricity, information security. Against theneed of the parallel high-precision time stamp, the system of the multi-channel high-precisiontime stamp based on GPS disciplined Rubidium atomic clock is developed. The main works ofthis paper are showed as follows:The methods of the multi-channel parallel stamp are studied. Based on the timedifference between the pulse to be stamped and the reference pulse, the stamping method isproposed. The uncertainty of each channel can be achieved100ns while parallel stamping, also,the relative stamping accuracy among every pulse improves to be better than1ns.To improve the accuracy and stability of the reference pulse, various errors of the timingGPS receiver is analyzed and the distribution of errors is studied. Under the characteristic ofthe Rubidium atomic clock, the model of the GPS disciplining Rubidium atomic clock isresearched. The estimation method of the clock parameter with Least Squares fitting andKalman filter is compared and analyzed. By the crystal oscillator precisely controlled, theaccuracy of the reference pulse will be improved to be less than100ns and the stability will beup to2e-11/s.On the basis of the multi-channel time interval measuring and the time stamp method,combining the functionality and performance of the requirement of the system, based on thedetailed analysis of the technical route, the instrument of the multi-channel time stamp isentirely designed. And all of the hardware and software are achieved, developed a prototype.At the same time a prototype is developed.On the hardware implementation, with the actual requirement of the test, the measuringrange of the time-digital converter chip is extended to achieve the rapid measurement of alarge range while achieving the accurate measurement of the small-scale.In the software implementation, using the multi-threading technology, the parallelprocessing of the several serial data interfaces for the multi-channel time stamping system isachieved. While the time information of the pulse to be stamped is displayed and the fine timeis displayed to be graphical. Of course, the time information is saved and the time differencemeasurement is controlled. In order to analyze the performance of the time stamp instrument, the actual test isdesigned and the device is tested from the accuracy, precision and deviation. The experimentalresults show that the device can be stamping concurrently for seven pulse signals, theuncertainty of the time stamp for the one pulse is less than100ns, the relative deviationbetween every pulse is less than1ns, the resolution of the time stamp is better than81ps. Thedevice meets the design requirements.