Antenna construction

High-precision satellite communication

Hollow shaft gears for antenna systems

The alignment of large parabolic antennas, such as those used for communication with near-Earth satellites, requires high positioning accuracy. This applies both to the azimuth (the angle between the meridian and vertical plane of a celestial body) and the angle of elevation. The control of these antennas, which have dish diameters of up to 17 metres, requires high torsional and moment rigidity in addition to high reduction ratios. Nabtesco´s compact RV-C gearboxes are ideal for this application.

High precision

The cycloidal gears of the RV-C series are designed for high repeatability and path accuracy – indispensable for satellite control!

Low vibration

The two-stage reduction principle minimises vibrations and mass inertia, while allowing higher reduction ratios.

Hollow shaft

A hollow shaft with a large diameter allows the feed-through of data cables and supply lines, which facilitates the design and construction of antennas.

Open centre for cables and supply lines

The unique cycloid-bolt construction makes it possible to design precision gears with high repeatability and path accuracy. This is likewise indispensable for satellite control. The integrated angular contact ball bearings absorb the forces and moments of wind gusts and allow the support of larger antennas. Nabtesco gears also combine high rated torques with backlash well below one arcminute! In the case of peak loads, such as in emergency stop situations, they can easily withstand loads as high as five times the rated torque.

The large hollow shaft of the RV-C gearboxes allows the feed-through of data cables, supply lines or drive shafts. This facilitates the design and construction of antennas especially when space is at a minimum.

Space for cables and hoses

The large hollow shafts in our compact and precise hollow shaft gears allow the feed-through of cables, hoses and supply lines through the cycloidal gear. The hollow shaft is designed to rotate at the output speed instead of being rigid, which makes it possible to measure the output speed directly by means of a sensor on the hollow shaft. Nabtesco offers hollow shaft gears as a ready-to-install solution with a coupling and motor flange.

Our gears for antenna systems


Hollow shaft precision gearboxes
- Component sets -


Hollow shaft rotary indexers


Solid shaft precision gearboxes
- Component sets -

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