Table of Contents
Advertisement
RC4600 ACU Board Set
2.1.1.2.2.3 LOCATE
The LOCATE mode performs a calculation of the pointing angle (3.2.1) to a selected satellite based on
the RC4600's estimate of where the antenna is positioned (lat/lon) and oriented (Antenna Bearing). After
the calculation is performed, the user may initiate an automatic antenna movement to locate the selected
satellite.
When the LOCATE mode is first entered, the following screen appears.
A N T :
S A T : G A L A X Y 2 8
< 1 > S E L E C T N E W S A T
ANT: 38_57N 94_45W 178.9
The ANT: field shows the RC4600's current estimate of antenna position. If no estimate of antenna
position is available, the RC4600 will automatically attempt to obtain position information from the
navigation sensors (GPS receiver and compass) if present prior to displaying the initial screen above.
Mount Position Initialization. In order to calculate a pointing solution, the RC4600 requires knowledge
of the mount's "position". The three components of mount position are latitude, longitude, and true
heading.
The current latitude, longitude and true heading where the RC4600 believes the antenna is positioned are
displayed on the top line. The position data obviously affects the pointing angle that the RC4600
calculates and is displayed as a crosscheck for the user in case the vehicle has been moved and the
RC4600's position has not been updated. If the lat/lon or heading data is not considered valid by the
RC4600, asterisks will be displayed in the appropriate field and the "parameter needed" message will be
triggered in the location readiness field.
The RC4600 polls the GPS receiver first to get latitude and longitude information. If no communication
with the GPS is received, the error message "GPS OFFLINE" will be displayed. In this case the interface
between the RC4600 and the GPS receiver would need to be checked. If the RC4600 is communicating
with the GPS receiver but the GPS indicates it has not yet been able to generate a valid lat/lon, then the
message "NAV NOT READY" will be displayed. The "NAV NOT READY" situation should typically not
last for more than a minute. If it does, then investigate whether the GPS receiver's view of the sky is
blocked by buildings, etc.
Chapter 1
3 8 _ 5 7 N
9 4 _ 4 5 W
8 9 . 0 W
29
1 7 8 . 9
L O C A T E
A Z :
- 4 . 6
E L :
4 4 . 8
R E A D Y T O L O C A T E
Introduction
Advertisement
Table of Contents
