GBAS/SCAT-I Mode (Options R&S
EVSG-K4/-K5)
R&S
®
EVSG1000
174
User Manual 1178.6227.02 ─ 06
Figure 6-3: Final Approach Segment (FAS) diagram, according to [1]
LTP/FTP = Landing Threshold Point/Fictitious Threshold Point; point at the center of the landing runway,
defined by its WGS84 coordinates
GPIP
= Glide Path Intercept Point; the point where the final approach path intercepts the local level plane
FPAP
= Flight Path Alignment Point; point at the end of the runway that in conjunction with the LTP/FTP
defines the geodesic plane of the precision final approach, landing and flight path.
TCH
= Threshold Crossing Height
GPA
= Glide Path Angle; angle at the TCH that describes the intended angle of descent at the final
approach path.
The coordinates of the LTP/FTP are defined in WGS84 coordinates. In this coordinate
system, a location is identified by three coordinates, the altitude, the latitude and the
longitude.
6.1.4
Time Slot Synchronization via PPS
The GBAS/SCAT-I signal is synchronous to the PPS signal of the GPS system. With
the help of this synchronization, the GBAS/SCAT-I signal is assigned to eight time slots
(twice a second).
If the R&S
EVSG1000 finds a valid PPS signal at its selected trigger connector, the
status line of the display indicates "PPS Locked". In this case, the R&S
EVSG1000 can
analyze the GBAS/SCAT-I signal and detect the individual GBAS time slots.
If no valid PPS signal is detected, the R&S
EVSG1000 still analyzes the GBAS/SCAT-I
signal and tries to synchronize to the GBAS/SCAT-I burst raster. In this case, the status
line of the display indicates "Burst Locked". Without PPS synchronization, signal timing
and slot positions may not be correct.
6.2
GBAS / SCAT-I Measurement Information
The following measurement information is displayed in all GBAS / SCAT-I views.
GBAS / SCAT-I Measurement Information
