Dual-channel rotary joint for the 26.5 to 40 GHz frequency band up to 100 W CW

January 21, 2013 // By Julien Happich
The Engineering Division of Link Microtek has introduced the AM28RJUD, a dual-channel rotary joint that is specifically aimed at applications in Ka-band satellite communications systems on board aircraft or unmanned aerial vehicles.

The AM28RJUD features a WR28 waveguide channel for transmissions in the 26.5 to 40 GHz frequency band at up to 100 W CW, combined with a DC-2 GHz coaxial channel for receive signals. The rotary joint complies with the relevant requirements of the RTCA DO-160 [AD/1] specification, which details environmental conditions and test procedures for airborne equipment - covering parameters such as temperature, pressure, humidity, shock and vibration.

To operate at the high frequencies of the Ka band, the device is small: measuring only 42 mm between waveguide flanges, with an overall length of 120 mm between coaxial connectors.

The non-contacting design of the waveguide channel makes for an inherently high power handling capability of 100 W CW, together with a VSWR of 1.2:1 and
a typical insertion loss of 0.6 dB. The coaxial channel has a VSWR of 1.5:1 and an insertion loss of less than 0.4 dB, while isolation between the two channels is better than 65 dB. Fabricated in either aluminium or brass as standard, the AM28RJUD can be specified with a variety of different coaxial connectors, including SMA, N-type and TNC. As an option, the device can also be supplied with an integral slip-ring assembly.