Higher Degree of Miniaturization with Split Rectangle Resonators

In this paper, a new concept for bandstop filters based on complementary split rectangle resonators etched into a single metal layer is proposed. Using equally length complementary resonators is the key behind the concept. This results an extreme improvement of the first spurious stopband with smooth insertion loss over a very wide bandwidth. The effect of adding slots in the proximity of the resonators is studied. These structures could be of interest for applications in band stop filters where miniaturization and compatibility with planar technology are key issues.