A Picosecond Resolution Time Digitizer for Laser Ranging
- 1 January 1978
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Nuclear Science
- Vol. 25 (1) , 75-80
- https://doi.org/10.1109/tns.1978.4329280
Abstract
The Time Digitizer capable of covering a range of 0.34 sec in 9.76 psec increments is described. The time interval between a pair of start-stop pulses is digitized coarsely in 20 nsec periods by a very accurate 50 MHz reference clock. The residual fractions of a clock period at the start and the stop end of the measured interval are stretched in two interpolators and digitized in 9.76 psec increments. An equivalent digitizing frequency of 102.4 GHz is thus achieved. The digitizer is built in a CAMAC minicrate and communicates via a standard crate controller. It is intended for use in the laser ranging between ground stations and the Laser Geodetic Satellite (LAGEOS). It is shown that the distribution in any two adjacent 9.76 psec channels of a small number of identical test time intervals is essentially binomial. The performance of the digitizer and test results are given.Keywords
This publication has 2 references indexed in Scilit:
- Review of Sub-Nanosecond Time-Interval MeasurementsIEEE Transactions on Nuclear Science, 1973
- Digital Time IntervalometerReview of Scientific Instruments, 1968