Renaissance Electronics has developed a new low loss, high isolation waveguide isolator for Satcom applications that covers 43 – 46 GHz with industry standard interface of WR 22. With loss of 0.5 dB and 18 dB isolation, it is ideal for low noise figure Satcom receivers.

http://www.rec-usa.com/Data%20Sheets/43-46GHzWaveguideIsolator2WR22NB.pdf