GPS Measurement Synchronisation

GPS time synchronisation for data acquisition systems

Time synchronisation over the world

Synchronizing Measurement Data

Measurements with several devices need a synchronization of the time base for bringing together all measurement data later on. If the measurement devices are in close proximity the synchronization can be done over a specific cable. Depending on the device type this can be done with a simple reference clock, over IEEE-1588 and Ethernet or by a device specific protocol.

When the distances between the devices are too large or using of cables is not possible a synchronization based on GPS is the ideal solution.

GPS as Reference Clock

Among the main function of determine the actual position, GPS is also a precise time source. Most of the GPS receivers have the functionality to readout the absolute time (UTC) per software. But this is not sufficient for synchronization as the software readout leads to unpredictable delays. Industrial GPS receivers have therefor a pulse per second hardware output which allows timing precision of 1us and better.

TPCE and GPS

Elsys TPCE boards and all products based on them can be synchronized over GPS. Therefor all devices needs their own GPS receiver. On the availability of an Ethernet or WLAN connection all devices can be controlled and monitored from one central unit. An autonomous operation of all devices individually is possible too.

Trigger Transmission

On the availability of an Ethernet connection trigger events can be transmit by a LXI event message to other devices in the network.

Supported Hardware

TPCE PCIe Data Acquisition Board TraNET PPC portable data acquisition system TraNET EPC 19'' Rack data acquisition system

Specification

  • Precision to absolute time: ± 1 us
  • Long time stability during the measurement: no drift, locked to GPS