A S-band monolithic integrated switched filter bank has been designed to realize tunable working center frequency, and a tuning range of 12.9% from 2.7 to 3.05 GHz was achieved with interval of 50 MHz. The switched filter bank is designed using 8 eighth-order step impedance resonators (SIR) band-pass filters arranged in parallel rows. Microelectromechanical Systems (MEMS) switched circuit is integrated above filters for monolithic design combined with low temperature co-fired ceramic (LTCC) technology. The SIR bandpass filters are designed to resist Electromagnetic Interference(EMI) between components and introduce cross coupling to bring two transmission zeros and better out-of-band rejection. The monolithic integrated switched filter bank is only 74 mm×24 mm×2.5 mm, which realizes the monolithic integration of the device and enhances the reliability. The measured results show that the insertion loss and out-of-band rejection are in good working condition.
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