Initiating a track on an inclined orbit satellite – Research Concepts RC2500 User Manual

Page 45

Advertising
background image

38

RC2500 Antenna Controller

Chapter 4

Inclined Orbit Satellites

Research Concepts, Inc. • 5420 Martindale Road • Shawnee, Kansas • 66218-9680 • USA

www.researchconcepts.com

15 4.57 457

20 6.10 610

23 7.00 700

24 7.32 732

The Max Track Error and Search Width CONFIG mode items are discussed in section 4.2. The default

values are 10 and 3, respectively. The Max Track Error is specified in tenths of a dB. When initiating a

track on an inclined orbit satellite for the first time, it is probably best to leave these parameters at their

default values. See the section on tracking problems at the end of this chapter for more information on

the Max Track Error parameter.

The Search Enable CONFIG mode item is used to enable or disable the Intelli-Search feature when the

SEARCH sub-mode is active. When disabled, the SEARCH sub-mode will simply prompt the user to

manually jog the antenna (via the front panel) back onto the satellite and hit the ENTER key. When the

ENTER key is pressed, control will transfer to the STEP TRACK sub-mode. The Intelli-Search should be

disabled for transmit applications, or when the RC2500B is interfaced to an antenna which moves very

slowly.

4.4.3

Initiating a Track on an Inclined Orbit Satellite

This section describes the process of initiating a track on an inclined orbit satellite. It is assumed here

that the user has entered the configuration data outlined in sections 4.4.1 through 4.4.2 into the controller,

and that there are no alarm messages flashing on the bottom row of the display. If there are active

alarms, they must be cleared before initiating a track on an inclined orbit satellite.

The steps required to initiate a track are very similar to the procedure used to program a geostationary

satellite into the controller's memory. A track is initiated from SETUP mode as follows:

1. Go to SETUP mode and use the jog keys to manually align the antenna with the satellite. The

2. Use the SCROLL keys to select the satellite name. Press ENTER to assign the name to the satellite.

If the name is not in the list, go to step 3.

3. If the satellite name was found, skip this step. If the name was not in the list, select the USER entry.

Then use the SCROLL keys to scroll through the alphanumeric list to key in the name of the satellite.

Press the ENTER key to select each letter/number, and press ENTER at the "*" to terminate the

entry. A blank space can be entered by pressing SCROLL UP once and SCROLL DOWN once.

4. 'IS THIS AN INCLINED ORBIT SAT'. Hit the YES key in response to this question.

5. 'ENTER SAT LON LLL.L'. Use the number keys and the decimal point to enter the numeric portion of

the satellite longitude; i.e., if the longitude is 100.5 West, key in '100.5'. Terminate the entry of the

numeric portion of the satellite longitude by hitting the ENTER key. The BKSP key may be used to

backspace over any incorrectly entered data any time before the ENTER key is pressed.

6. The user is next prompted to enter the direction associated with the longitude entry. Hit the 4 key to

specify an East longitude, and hit the 6 key for a West longitude. Hit the ENTER key to terminate the

entry.

7. 'SELECT BAND 0-C,1-K,2-C&K,3-L'. If the satellite is a hybrid which has both C and Ku band

transponders, select 2. Otherwise, key in the appropriate band designation.

8. 'SAT INCLINATION (2-16 DEG):' See the Appendices for a list of inclined orbit satellites and a

nomograph which may be used to determine the inclination of the satellite's orbital plane to the

earth's equatorial plane. Key in the appropriate value, followed by ENTER. Note that very few

communications satellites have an inclination greater than 6 degrees. If you are unsure of the

satellite inclination, try 5 degrees.

9. The user is next prompted to specify the horizontal and vertical polarization values for the satellite if a

single port feed was specified (or a single polarization value if a dual-port feed was specified). Use

the CW and CCW keys to skew the polarization, and the H and V (or <enter>) keys to set the

polarization. 'INITIAL TRACK POL (H OR V)?' Press the appropriate key for the polarization of the

initial track.

10. Control will transfer to TRACK mode. 'TRAK' will be displayed in the upper right hand corner of the

display. If the user designated a hybrid satellite (both C and Ku band), the following prompt appears:

Advertising