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Novel wide passband microstrip bandpass filters with broader stopbands are provided in this paper. The proposed bandpass filters are composed of the stepped coupled line and two short-circuited stubs. The electrical length of the stepped coupled line is a quarter of wavelength so that the proposed filter is compact size. Moreover, the stepped coupled line with weak-strong-weak coupling results in a wide stopband. Furthermore, with short-circuited stubs connected at the input/output port, there is a steeper passband skirt and broader passband. In addition, the agreement between theoretical prediction and measurement validates our proposed structure.