When the ratio of waveguide diameter to wavelength is not too large, bends can be negotiated with low loss in continuous bends with special curvature. Some examples:
High power 30˚ continuous curvature bends in 31.75 mm waveguide for HE11 mode at 110 GHz
High power 90˚ continuous curvature bend in 44.5 mm waveguide for TE01 mode at 11.4 GHz
High power 90° continuous curvature bend in 44.5 mm waveguide for HE11 mode at 28 GHz
James Anderson andersonjp@fusion.gat.com (858) 455-2709
John Doane, GA-MFE Technologies doane@fusion.gat.com (657) 500-2001