KVH Industries TracVision Cruiser User Manual page 29

A Guide to TracVision Cruiser
TracVision Cruiser
Automated Procedures
3-2
The system carries out a number of automated steps at startup.
For reference, these steps are outlined in Table 3-1 below.
Step
Table 3-1
Antenna Unit Initialization
IRD Identification
Satellite RF Threshold
Satellite Search Modes
Search Mode 1
Reacquisition Search
(Search Mode 2)
Search Mode 3
Fine-tuning/Satellite Verification
Actions
The microprocessor circuitry does a
basic self-test of the hardware and
software associated with the
antenna unit and calibrates the
antenna gyro.
The microprocessor next queries
the IRD to determine whether it is a
DIRECTV or DISH Network IRD.
Based on the IRD type, the system
will then set various system
variables to ensure that the correct
satellite is found during Search
Mode.
The antenna is pointed at the north,
south, east and west horizons to
determine the background noise
level and to calculate the minimum
signal level required for satellite
acquisition.
The system design includes three
search modes to acquire the
satellite.
The antenna makes four complete
revolutions at the saved elevation.
The antenna will search in a
"window" of 6˚ around the satellite's
last known elevation.
The antenna conducts a complete
sky search, making continuous
revolutions at steadily increasing
elevations (from 20˚ to 70˚).
When a signal is detected, the
antenna interrupts the search mode
and begins a procedure to fine-tune
the position for maximum signal
strength. When the signal peak is
found, the IRD is queried to
determine if it can decode the
peaked signal. If it is able to
decode and lock onto the signal,
then the system enters tracking.