The 90-degree twister of polarization
Microstrip array of printed S-shaped metal particles has resonant feature to transform linear polarization of normally incident plane wave to orthogonal linear polarization of the reflected field. This very thin structure can perform full transformation of linear polarization to orthogonal.
Configuration of microstrip array of S-shaped particles as well as frequency dependencies of reflection coefficients are shown in the Figures below. Strip parameters are a=3 mm, f1 =120 degrees, 2w=0.1 mm, f2 =0. Array periods are identical and are 10 mm long, substrate permittivity is 2 and substrate thickness equals to 1.5 mm.
Prosvirnin S.L., Transformation of polarization when waves are reflected by a microstrip array made of complex-shaped elements, Journal of Communications Technology and Electronics, 1999, vol. 44, no. 6, p. 635-639.
Просвирнин С.Л., Преобразование поляризации при отражении волн микрополосковой решеткой из элементов сложной формы, Радиотехника и электроника, 1999, т.44, 6, 681-686