A corrugated horn with broadband window for W-band gyro-devices

A upgraded W-band corrugated horn including a broadband vacuum window for use in gyro-devices has been designed, constructed and experimentally measured. The horn and multi-layer vacuum window converts a cylindrical TE₁₁ mode into the free space quasi-optical TEM₀₀ mode over the frequency band of 90-100 GHz with a reflection better than -30 dB and a coupling efficiency of ~99.4%.