Renaissance has developed a new Ka band waveguide isolator that is designed for downconverters used in space applications. The isolator can operate between 27.5 – 31 GHz with 0.15 dB insertion loss over 5% bandwidth and 20 dB isolation and return loss. The isolators can handle 1 W forward and reflected RF power levels. All epoxy and RTV used are space qualified.

http://www.rec-usa.com/Data%20Sheets/2WR34NA.pdf