Super miniaturized LTCC filter using novel composite resonators

To develop a miniaturized LTCC bandpass filter, new resonator topology is proposed. A parallel sub-resonator and a series sub-resonator are connected in parallel to form a composite main-resonator. Parasitic components are positively incorporated in each sub-resonator, where the space is efficiently utilized in multiple ways. It is inspired from a CRLH-resonator with left-handed and right-handed components. The combination of sub-resonators makes the resonance frequency much lower, resulting in filter miniaturization. The resonator performance is analyzed. An experimental filter is fabricated with state-of-the-art LTCC technology. The simulated and the measured results show very good agreement. Thus, it is confirmed that the proposed filter is effective for filter miniaturization.