A ultra-wideband bandpass filter with notch implementation

A compact ultra-wideband (UWB) bandpass filter using a rectangular ring with parallel coupled line feed is proposed in this paper suitable for wireless communication applications within the unlicensed UWB set by the FCC. The notched band has been introduced by using a new technique involving an asymmetric parallel-couple line (single notch) connected at a line feed to reject any undesired radio signal in UWB passband. The notched frequency and bandwidth of the notched filter can be controlled by the length and width of asymmetric parallel-coupled line. The proposed filter demonstrated a good agreement between simulated and measured responses from 3.0 GHz to 11 GHz and rejection performance more than 10 dB at central frequency.