A dual-band band pass filter using rings resonator for space communication

A Dual-band BPF with parallel-coupling feed and ring resonators is designed and simulated. Parallel coupling feed, results in good coupling between input and output and good isolation between frequency bands by generating deep zero between passband. Ring resonator make filter as dual-band by shifting higher order resonating modes to desired frequency range. Filter response results in two frequency bands 4.808-5.216 GHz and 8.348-9.043 GHz covered in C and X band respectively. Some applications of these bands are mobile communication, Radio astronomy, space research and aeronautical radio navigation. Compact size (131 mm²), Small group delay (<;0.43 nanosecond), large attenuation in stop band (larger than 20 db till 16 GHz), higher 3dB FBW (21.47% and 19.87%), small insertion loss, large return loss in passband are some advantageous factors of proposed filter design. Simulation is done using CST microwave studio 2013.