For many mobile satellite communication systems developed these days, there is a requirement to significantly reduce the height of the radomes under which the SatCom systems are installed. This is to improve their drag coefficient.

This means that less installation space is available for the antenna as well as for the whole pedestrial. Due to the increasing demand for low profile rotary joints to be used in SatCom radomes, SPINNER has taken up the challenge and developed the dual channel coaxial rotary joint described here. The new design developed by SPINNER allows us to reduce the height of the profile by at least 2.5cm or 1in. Since the height of the rotary joint is reduced, the overall system can be built lower and can thus help save fuel, e.g. on an aircraft.

This SPINNER design sets new standards in terms of shape, size and RF properties.

It is particularly in the ranges DC-4.5 GHz (CH 1, CH2) and 10.75-12.75 (CH2) and 13.7- 14.5 GHz (CH1) that this dual channel rotary joint stands out for its extremely low insertion loss and low VSWR.

A special highlight of this rotary joint is that it can also transmit direct current for the power supply, as can all contact-based rotary joints in the SPINNER portfolio. In addition, the excellent isolation between both channels is over 50dB (typical value: 60dB).

The typical RF parameters are better than the values guaranteed in the specifications. The ambient temperature range between -55°C and +70°C also meets all requirements and conditions for military applications.

The standard protection rating for the rotary joint is IP54 (BN 153107). Due to the selected shape, it is also possible to integrate a special sealing assembly within the same mechanical dimensions (BN 153106), which allows a higher protection rating of IP65. The only change that this brings about is a slight increase in the starting torque from 0.05Nm to 0.08Nm.

This rotary joint weighs about 130g, so in spite of its larger diameter it is not heavier than any comparable rotary joints on the market.