R&S M3SR 4100 Series, Operating Manual

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Operating Manual 6175.4760.02 – 01 4.159
M3SR Series 4100 SECOM-H
For technical reasons, it is not possible to maintain synchronization forever. The R&S M3TR
Series provides functions for automatic re-synchronization:
• GPS as time source: Whenever synchronization is lost, the radio will re-synchronize to
the net by updating its time with the current GPS time. No further user interaction is re-
quired.
• Time Beacon (TB): The radio automatically takes care of new synchronization before
synchronization is lost. If the TB function is not active, it may be required to perform a
TAQ from time to time. This is indicated by the NSYN (not synchronized) message at the
display. The Time Beacon function does not replace the need for an initial TAQ. More-
over, when switching TB functionality OFF and ON again, a new TAQ has to be per-
formed, i.e. an initial TAQ is necessary every time TB functionality is enabled.
When the Time Beacon is active, the radio will transmit data automatically and without
user interaction. Turn off the Time Beacon to avoid this.
When the radio is turned off, net time can only be updated with reduced accuracy. Manual
TAQ may be necessary even if Time Beacon is active.
4.8.1.4 Linking
SECOM-H is a link-oriented communication system, using physical and logical links.
A physical link exists if at least two radios are able and prepared to receive one another. This
means the participating units must be synchronized. So in general a link setup is required to
establish a link. During this link setup SECOM-H provides for synchronization with the other
participating units and transmits address and service information.
A logical link exists if one participating unit is transmitting and one or more other participating
units are receiving this communication.
Simultaneous transmission and reception is not supported by SECOM-H.