Dual-channel high-power WR28 waveguide rotary joint for Ka-band sat comms

The new 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 defence or commercial airborne systems such as satcom uplinks in unmanned aerial vehicles, the new rotary joint features a high-power/low-loss WR28 waveguide transmit channel, together with a coaxial receive channel offering a high current rating of 2A at 24VDC, 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 29-31GHz, with an average power rating in excess of 50W, a typical insertion loss of just 0.5dB and a maximum VSWR of 1.7:1. The receive channel can handle frequencies up to 3GHz at an average microwave power of 1W, and its typical VSWR and insertion loss are specified as 1.5:1 and 0.25dB respectively. Designed and manufactured at Link Microtek's premises in Basingstoke, this 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 compact overall dimensions of just 36mm (D) x 90.3mm (H), with a 50mm-diameter UBR320 bulkhead flange as standard. Other rotary-joint configurations and sizes are available on request, tailored to suit specific antenna requirements, says the company.