Single trapezoidal patch resonator bandpass filter

Isosceles trapezoidal resonator bandpass filters are proposed, and filters performances are calculated and optimized, and validity of the design is demonstrated by experiment. With etched trapezoidal fractal-shaped defection in patch, filters performances are greatly improved, and the bandpass filters can implement a controllable, dual and wide passband with a maximum relative bandwidth of 60%, and insertion loss of less than 1 dB, and transmission zeros, et al. The designed filters have outstanding advantages such as simple and compact structure, small size, nicer frequency selectivity and so on, and can be quite useful for applications in future wireless communication systems.