Accurate Computer Timing Through Gps System
By MarkWilliams
The global positioning system (GPS) is a combination of many number of orbiting satellites. The basic objective of this is to provide precise positioning information that is useful for the navigation purposes. To calculate the positioning it uses the accurate timing information and triangulation. The accurate timing system is also used for the computer network time synchronization purposes. The orbiting satellites have onboard atomic clock that provides highly precise time. The timing information is used to get the network timing with the help of NTP servers. There are different types of equipments that are needed to process signals for time and frequency applications.
Time remains same world wide and does not vary with the time zones and hence is referred to Universal Coordinated Time (UTC). The time send by the satellite is not affected by the time zones and hence it continuously transmits precise time information. The time is not affected by the leap seconds and is ahead of UTC time. That’s reason for which you can adjust the time to get the UTC time for the computer network time synchronization.
However, the satellites broadcasts very weak low power radio signal with two frequencies, L1 and L2. The first frequency is intended as a civilian band broadcast at a frequency of 1575.42. The later frequency L2 is intended to provide stronger signal transmission for the future. The signals can pass through glass, plastic and clouds and always move in a straight line though they can not pass through the metals and brickwork. That’s why it is imperative to place the antenna in a place where it can face the clear sky. There are some ideal locations for it such as on the roof top and if it is impractical to place it on the roof top then you can place it in the side
of a building or near a window.
As the system provides subscription free accurate timing resource, many computer networks use this as an accurate timing reference for computer synchronization. The reference clocks are utilized by precise NTP server as an external synchronization source. The accuracy by the system is enough for the computer network timing applications. The time and positioning information by the servers is according to the standard NMEA protocol and usually they are transmitted as sentences of character strings. This is how the system is used to provide the accurate timing for the computer networks.
