R&S M3SR 4100 Series, Operating Manual

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Operating Manual 6175.4760.02 – 01 5.27
M3SR Series 4100 Initiating a GPS Information Request (Pull, Scheduled, as Controller Feature)
5.2.2.8 Initiating a GPS Information Request (Pull, Scheduled, as Controller Feature)
By means of softkey 'Scheduled PULL' the operator of a controller radio can request (pull)
the GPS position from all or from a single participant using a scheduled transmission (see
sect. 5.2.1.2 Types of GPS Transmission).
Standard pull actions (be it request or response) can be executed only when the GPS time
signal (required for scheduling) has been received at least once. This is due to the fact that
standard pull transmissions are scheduled in order to avoid on-air collisions with other
(scheduled) GPS transmissions. Thus, using the standard pull mode is more reliable than
the immediate pull (see sect. 5.2.2.7 Initiating a GPS Information Request (Pull, Immediate-
ly, as Controller Feature)).
A standard pull request can be addressed to all participants (BROADCAST) or to a single
participant. The selection process of the addressed participant(s) is described in
sect. 5.2.1.3 Addressing of GPS Transmissions.
In case the GPS signal has never been received by an addressed participant, the participant
will not respond to the standard pull request. The participant then appears to be "absent" to
the controller, i.e. it does not appear in the list of received GPS positions (see
sect. 5.2.2.10 List of Received GPS Position Information). In this case, the operator of the
controller may use an immediate pull request (see sect. 5.2.2.7 Initiating a GPS Information
Request (Pull, Immediately, as Controller Feature)) in order to pull a particular participant not
responding. If an addressed GPS participant has currently only limited or no GPS satellite
visibility, it will still respond by transmitting empty GPS positioning information using a sched-
uled transmission.
The reception of the GPS position received from the addressed GPS participants is de-
scribed in sect. 5.2.2.10 List of Received GPS Position Information.
Softkey Type Description
Listbox 1. Press softkey ‘Scheduled PULL'.
2. Select all (BROADCAST) or a single partic-
ipant (PTCP) from the list box.
3. Press softkey ‘ENT’ to confirm selection and
transmit an scheduled pull request to all
(BROADCAST) or to a single participant.
After the request was sent, the ‘Scheduled
PULL’ button is enabled again.