Italsat 1

Italy

Spacecraft n°:

Italian spacecraft n°: 7


Launch data:

Designation 21055 / 91003A
Launch date 15 Jan 1991
Launch site Ko, ELA-2
Launch vehicle  Ariane-44L (V41)
Mission:Communications
Geostationary orbit:
Perigee / Apogee 35815 x 35951 km
Eccentricity 
Inclination 12.3 deg
Period 1441 min
Location 13.2°E


Specifications

Prime contractor Selenia Spazio
Platform Italsat
Mass at launch 1850 kg
Mass in orbit 1122 kg
Payload mass 273.4 kg: transponders: 198 kg, antennas: 75.4 kg)
Dimension 3.5 x 2.7 x 2.3 m
Solar array 21.8 m span
Stabilization 3-axis
DC power EOL: equinox: 1760 W, solstice: 1633 W
Payload power 937 W
Design lifetime 6 years

Equipped with 1 (+1 backup) 1 W propagation beacon, EIRP 27 dBW at 20 GHz for telemetry

Also aboard: a 40 GHz beacon phase modulated by a 505 MHz coherent subcarrier, and a polarization-switched (but otherwise unmodulated) 50 GHz beacon

End of life

Out of serviceJan 2001
Cause-


Ka-band - National beam (20/30 GHz)

Main transponders
Backup transponders  
Power 20 W (TWTA)
Bandwidth 36 MHz
Coverage Italy (1.55 x 1.06 deg)
EIRP max 46.2 dBW
G/T 5.5 dB/K
SFD -99.6 dBW/m²
Polarization linear V (both upload and download)

Those transponders are intended for TV feeds

Ka-band - Multi beam

Main transponders 6 in 20/60 GHz
Backup transponders 2 in 20/30 GHz
4 in 20/60 GHz
Power 20 W (TWTA)
Bandwidth 120 MHz
Coverage Italy (6 spots of 0.49°)
EIRP max 57 dBW
G/T 16.1 dB/K
Polarization linear V (both upload and download)

The spot beams carry domestic telephone traffic with a total capacity of about 12,000 voice channels. Each beam operates in the SS-TDMA mode with QPSK modulation at 147 Mbits/sec in a 100 MHz RF bandwidth. On-board regeneration (demodulation and remodulation) is provided, and the beams are fully interconnected by a space-division switching matrix. Satellite resources can be allocated on a call-by-call basis or left as assigned until changed by ground control. Reconfiguration is by ground command; the satellite is not autonomous.


Ref: #15 - update: 12.11.08