That is true. One of the fun things illustrating first-hand how microwave&#x2F;millimeter wave and fiber are the same thing is if you ever get to handle a 120 GHz band waveguide&#x2F;feed. Some radar and military stuff operates in the 120 band.<p>It&#x27;s so incredibly tiny and narrow compared to a 11 or 18 GHz microwave waveguide. Then imagine continuing to make it narrower while increasing the frequency, follow that to its logical conclusion and you have imagined a 9&#x2F;125 fiber.