GBAS/SCAT-I Mode (Options R&S
EVSG-K4/-K5)
R&S
®
EVSG1000
129
User Manual 1178.6227.02 ─ 04
7.3.2
Frame View
Access
: [Meas] > "View" > "Frame"
To use the available spectrum most efficiently, despite the low data rate, GBAS trans-
missions use the Time Division Mulitple Access (TDMA) method (see also
ter 7.1.2, "Broadcast Timing Structure"
on page 123). Thus, multiple GBAS bursts,
even from different transmitters, can be sent in a single frame. To do so, the transmit-
ters must adhere to the time slots strictly. Nevertheless, time delays can occur during
transmission. The GBAS "Frame" view allows you to measure the time behavior of the
slots precisely.
You must provide a PPS signal for reference. To do so, connect an external GPS
device to the PPS In or Trigger In connector on the rear panel of the R&S
EVSG1000.
As opposed to the "Sequence" view, the "Frame" view displays the results of a single
frame only. By default, the most recently measured frame T is displayed. To display the
results for a different frame, use the
function.
The display is updated each time a complete frame has been measured, that is: every
500
ms. To freeze the current display for evaluation, you can pause the view update
on page 139). Data recording and streaming, however, continue as
usual. When updating is resumed, the displayed results in the view are updated.
The "Frame" view contains two different displays:
●
Chapter 7.3.2.1, "Frame Power Vs. Time Diagram"
GBAS / SCAT-I Measurement Views and Results
