Superconducting microstrip wide band filter for radio astronomy

A ninth order wide-band bandpass filter is presented for radio astronomy applications. The filter, for Jodrell Bank Radio Observatory, is designed to have a fractional bandwidth of 26.14% and a center frequency of 1.53 GHz. It uses both straight and hairpin resonators in order to achieve the wide bandwidth. In addition, the filter is integrated with two spur-fine notch filters for second harmonic suppression. Good agreement between simulated and experimental results is obtained.