HP RC3000 Manual Do Utilizador

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RC3000 Antenna Controller 
Chapter 3 
Detailed Operation 
 
 90  
3.2.2.9 Track 
The optional TRACK mode may be entered via the STORE or RECALL modes if the selected satellite 
has been described as having a inclined orbit. 
Details of TRACK mode are available in the separate appendix TRK describing inclined orbit tracking.  
The following descriptions give an overview of how tracking is performed. 
TRACKING INCLINED ORBIT SATELLITES.  The RC3000 tracking algorithm can be divided into three 
distinct stages - STEP_TRACK, MEMORY_TRACK, and SEARCH. 
AZIM: 31561        SIG:735(C)      TRACK 
ELEV: 11060        SAT:BRASIL A1 
 POL:   8.2       STEP:PEAKING       AGC 
JOGGING ANTENNA TO FIND MAXIMUM SIGNAL 
In  STEP_TRACK, the controller periodically peaks on the receiver' signal strength by jogging the 
antenna.  The time and position are recorded in a track table maintained in the controller’s non-volatile 
memory.  The interval between peakups is determined by antenna beamwidth (determined from antenna 
size and frequency band), satellite inclination and a user specified maximum allowable error (in dB).  
When a track table entry exists for the current sidereal time, STEP_TRACK switches to 
MEMORY_TRACK. 
In  MEMORY_TRACK, the controller smoothly moves the antenna to azimuth and elevation positions 
derived from entries in the track table.  The time between movements is determined by the same factors 
which govern the time between peakup operations in STEP_TRACK.  By increasing the maximum 
allowable error, antenna movements can be performed less frequently.  In MEMORY_TRACK, the 
accuracy of the track table is monitored by periodically peaking up on the receiver’s signal strength.  If the 
error exceeds a level set by the user, all entries in the track table are flagged for update. 
TRACK_SEARCH is entered when the satellite signal has been lost. The RC3000 utilizes Intelli-Search, 
an efficient search algorithm that minimizes errors associated with traditional box searches and frees the 
user from having to update vague search window parameters. This scheme accounts for the specific 
mount geometry, calculates the nominal trajectory for the satellite, and then searches in an area that 
coincides with the satellite's expected path.  When the satellite is located, the controller re-enters the 
STEP_TRACK mode. 
 
 
3.2.2.10 Remote 
In REMOTE mode the controller only responds to commands received via the built-in RS-422/232 serial 
port.  REMOTE mode can only become active if the Remote Mode Enable CONFIG item is enabled.  If 
REMOTE mode is enabled, it can become active either in response to receipt of a valid command from 
the PC.  Note that TRACK mode can process certain commands received via the serial port.  The RS-422 
communication protocol, interface specification and the RC3000 command set is found in Appendix REM. 
The REMOTE mode screen is similar to the MANUAL mode screen. Only the MODE key is active when 
REMOTE mode is active.