Mechanically Tunable Microwave Filter Based on Crossed Strip Gratings with Controllable Crossing Angle in Free Space

Resonant scattering of the plane electromagnetic wave from the crossed strip gratings situated in the free space is studied. The strips of the gratings are made of PEC-like material of nonzero thickness. When the crossing angle of this structure changes from 90° to 0° the frequency dependences of the scattered powers reveal the resonances, the frequencies of which depend on the crossing angle of the gratings in a wide frequency range. Experimental investigation of the crossed strip gratings in microwave frequency range shows a good coincidence with the theory based on Integral Functional Method.