The UTC receivers, IRIG time code signals, and bus level translators described thus far, temporally link the data acquisition stations and provide record-record correlation. As an example, Figure 7 assumes that there are three separate data acquisition stations in each of three clusters, each acquiring data from the same test. Such a system is representative of a missile test range where one cluster is located at the launch area, one at mid range tracking, and one at the impact area. Each cluster is equipped with a GPS Receiver generating time code synchronized to better than 1 Microsecond of UTC time and which is distributed to each processor in the cluster. As test data is digitized and composed into a data record, a preamble or trailer is created which contains, along with other overhead information, the time of acquisition as supplied from the bus level time code translator.
System requirements dictate the time resolution and accuracy requirements.
PLO type bus level translators and IRIG A or G time codes will deliver 1 microsecond absolute accuracy. Such systems would use an IRIG time code signal synchronized to UTC routed to each processor. The software routines that handle this time tagging process are aided by using a bus level translator that minimizes access latency. Systems using IRIG B time code and bus level translators that decode at carrier cycle resolution easily provide 1 millisecond accuracy.