Optical Timing Receiver for the NASA Spaceborne Ranging System. Part II. High Precision Event-Timing Digitizer.

摘要

The report describes the design of a high precision event-timing digitizer. The event-timing digitizer is basically a combination of the very accurate high resolution real time digital clock and an interval timer. Typically,the digitizer measures the time difference between a pair of start--stop events. The digitizer is started at the beginning each mission and like a clock,counts the time in a range of up to 131days in 19.5ps increments. The start pulse is generated each time the laser is fired and fed to one of the event inputs of the digitizer. The time between the leading edge of an event and the mission start pulse is digitized in a time shorter than 5.3mu s and stored in the digitizer's buffer register. (ERA citation 04:045299)