A wide-band HE11 mode window for millimeter wave gyro-TWAs

Broadband windows are critical components in gyro-TWAs and pose a great challenge to manufacture. They are required to have very low reflection whilst coupling in microwave power. Presented in this paper is the design, simulation and measurement of a wide-band (90 to 100 GHz) multilayer microwave window using the HE11 mode as the input microwave mode. The simulated performance shows a better than −30 dB reflection over a 10% bandwidth of 90–100 GHz. The measured window is in very good agreement with simulations.