Search results
Results from the WOW.Com Content Network
Voice announcement with sync pips. Telephone connection, ear n/a Manual sync only. NIST Automated Computer Time Service (ACTS) [27] +1-303-494-4774 +1-808-335-4721; Windows computer with dialup modem. ntpd with NIST/USNO/PTB Modem Time Services driver; ClockWatch Pro for Windows [22] USNO Master Clock modem time [28] +1-202-762-1594
The time from an atomic clock onboard each satellite is encoded into the radio signal; the receiver determines how much later it received the signal than it was sent. To do this, a local clock is corrected to the GPS atomic clock time by solving for three dimensions and time based on four or more satellite signals. [ 11 ]
These are high-precision timekeeping devices such as atomic clocks, GNSS (including GPS) or other radio clocks, or a PTP-synchronized clock. [29] They generate a very accurate pulse per second signal that triggers an interrupt and timestamp on a connected computer. Stratum 0 devices are also known as reference clocks.
The next step in atomic clock advances involves going from accuracies of 10 −15 to accuracies of 10 −18 and even 10 −19. [ a ] The goal is to redefine the second when clocks become so accurate that they will not lose or gain more than a second in the age of the universe .
A modern LF radio-controlled clock. A radio clock or radio-controlled clock (RCC), and often colloquially (and incorrectly [1]) referred to as an "atomic clock", is a type of quartz clock or watch that is automatically synchronized to a time code transmitted by a radio transmitter connected to a time standard such as an atomic clock.
Clock synchronization is a topic in computer science and engineering that aims to coordinate otherwise independent clocks. Even when initially set accurately, real clocks will differ after some amount of time due to clock drift , caused by clocks counting time at slightly different rates.
Modern telecommunications networks use highly accurate primary master clocks that must meet the international standards requirement for long term frequency accuracy better than 1 part in 10 11. [4] To get this performance, atomic clocks or GPS disciplined oscillators are normally used.
In electrical engineering terms, for digital logic and data transfer, a synchronous circuit requires a clock signal.A clock signal simply signals the start or end of some time period, often measured in microseconds or nanoseconds, that has an arbitrary relationship to any other system of measurement of the passage of minutes, hours, and days.