Link Microtek AM28RJD WR28 waveguide dual-channel rotary joint

The AM28RJD dual-channel rotary joint from Link Microtek provides an effective means of reducing component count and saving space and weight in the compact antennas that are used for Ka-band high-data-rate SOTM (satellite-on-the-move) communication systems.

Particularly suitable for military or commercial airborne systems such as satcom uplinks in unmanned aerial vehicles, the rotary joint features a high-power/low-loss WR28 waveguide transmit channel, together with a coaxial receive channel offering a high current rating of 2 A at 24 VDC, which enables it to power the antenna’s LNB and servo motors without the need for additional slip rings.

The central transmit channel has a frequency range of 29-31 GHz, with an average power rating in excess of 50 W, a typical insertion loss of just 0.5 dB and a maximum VSWR of 1.7:1. The receive channel can handle frequencies up to 3 GHz at an average microwave power of 1 W, and its typical VSWR and insertion loss are specified as 1.5:1 and 0.25 dB respectively.

The robust device is fabricated from lightweight aluminium with an Iridite finish. Right-angle waveguide bends are used on the transmit channel to save additional space, resulting in overall dimensions of 36 x 90.3 mm, with a 50 mm-diameter UBR320 bulkhead flange. Other rotary-joint configurations and sizes are available on request.