Optical configuration
Primary mirror:
– paraboloid with a diameter of 32 m
– surface RMS of 400 μm
– divided into 240 sectors, 216 of which are movable through a system of 244 digitally controlled actuators (active optics)
Secondary mirror (d):
– hyperboloid with a diameter of 3.2 m
– surface RMS
Newtonian and Cassegrain optical configurations
Focal length in Newtonian configuration (F1): 10.26 m
Focal ratio (F1/D): 0.321
Focal length in Cassegrain configuration (F2): 20.29 m
Focal ratio (F2/D): 0.634
Aperture efficiency
57% @ 5 GHz (measured)
50% @ 22 GHz (measured)
40% @ 43 GHz (measured)
Pointing accuracy:
– Azimuth axis 0.002 degrees
– Elevation axis 0.002 degrees
Frequency agility:
– Frequency change at Newtonian focus: 4 minutes
– Frequency change at Cassegrain focus: 3–4 hours
Movement speed:
– Azimuth axis 48 degrees/min
– Elevation axis 40 degrees/min