Showing posts with label time. Show all posts
Showing posts with label time. Show all posts

Tuesday, September 7, 2010

Timing is everything

Because of the distance between the stations, the LOFAR telescope uses a GPS-satellite-based clock/time source. The GPS receiver generates the time signal for the local computer and a 1-pulse per second signal (1PPS). Although not accurate over short timescales, this can be used to synchronise the station. For short times, a Rubidium reference is used to generate a 10 MHz reference signal. This is used by all the equipment to ensure simultaneous and accurate sampling throughout the system.



Caption 1 : The small GPS-antenna atop the RF-container.




Caption 2 : The Rubidium reference source within the equipment racks.