11.2 Antenna Unit: FB-1500/1250
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11.2 Antenna unit: FB-1500/1250
11.2.1. Overview
1. The Antenna unit for FELCOM-500 is “FB-1500”, and the one for FELCOM-250 is
“FB-1250”. The circuit configuration and the operations are almost the same.
Table 11.2.1 The major differences between the Antenna units
FB-1500 FB-1250
EIRP 22 dBW 15.1 dBW
G/T -7 dB/K -15 dB/K
Antenna gain Rx: 17.6 dBi, Tx: 18.2 dBi Rx: 11.6 dBi, Tx: 12.4 dBi
Beam width Approx. 22 degree (-3 dB) Approx. 50 degree (-3 dB)
Antenna
weight
21 kg 6.5 kg
Size
H : 728 (attachment included)
φ : 653
H : 349
φ : 410
Power
consumption
Approx. 40 W Approx. 40 W
Sensor
Note)
Clinometer (Inclination sensor) FB-1250:Rate Gyro
Note) The operations are the same for both sensors.
2. GPS data or Heading data will not be used for Antenna control such as satellite
searching or tracking.
However, GPS data is used for the Fleet Broadband system.
3. The Antenna unit has a tracking algorithm equipped which will acquire the satellite
signal by itself without having to execute any operation from satellite searching until
satellite tracking.
1. The Functions for the Major module
HPA Module:
Power amplifier
Front end Module:
An assembly of ATB (Antenna Tracking Board) and LNA (Low Noise
Amplifier). ATB controls the Antenna unit and communicates with the
Communication unit.