Time interval measurement
AssigneeRCA Corporation
InventorWalter R. Curtice
Life of this patent
Estimating the term…
Abstract
The interval between arrival of two time displaced signals is measured with a resolution less than 0.5 nanoseconds by electronic vernier techniques utilizing transferred electron logic device circuits. The first arriving signal triggers a first clock generator of pulse period T.sub.C, the pulses from which are counted by a first counter and a second counter. The second arriving signal triggers a second clock pulse generator having a pulse period T.sub.V, the first pulse therefrom disabling the first counter at a count of M. As T.sub.V <T.sub.C coincidence of the pulses from the two clock pulse generators will eventually occur causing disabling of the second counter at a count of N. Time interval .DELTA.T is computed from the formula: .DELTA.T=(N-1)T.sub.C -(N-M)T.sub.V.
Claims7
An apparatus having first and second input terminals adapted to received thereat an early pulse and a late pulse, respectively, comprising in combination:
- means responsive to the receipt of said early pulse at said first input terminal for producing a first series of said clock pulses of predetermined period T.sub.C, the first pulse therefrom correlated to the occurrence of said early pulse at said first terminal;
- first counting means responsive to said first series of pulses from said clock pulse means for counting said pulses of said first series and for producing a signal indicative of the count;
- second counting means also responsive to said first series of pulse from said clock pulse means for counting said pulses of said first series and for producing a signal indicative of the count;
- means responsive to the receipt of said late pulse at said second input terminal for producing a second series of clock pulses of predetermined period, T.sub.V, where T.sub.V <T.sub.C, the first pulse therefrom occurring when a number, M, of said first series of clock pulses have been produced, said first pulse correlating to the occurrence of said late pulse at said second input terminal, said first counting means having a terminal receptive of said first pulse of said second series for becoming disabled from further counting while producing a signal representative of said number, M;
- and
- means responsive to pulses from said means producing said first and second series of pulses, respectively, for producing a pulse indicative of the first coincidence of a pulse in said first series and a pulse in said second series, said first coincidence occurring when a number N, of said first series of clock pulses have been produced and when said second means for counting is producing a signal representative of said number N, whereby the values of M, N, T.sub.C and T.sub.V may be utilized to measure the time interval between the arrival of the early pulse and late pulse.
Dependencies are inferred from the claim text.