Compact multilayer coupled stripline LTCC filter with defected ground structure

A novel multilayer coupled stripline resonator structure is introduced to realize miniature broadband band-pass filter using low temperature co-fired ceramic (LTCC) process with defected ground structure (DGS). Wide bandwidth and good selectivity are obtained by exploiting four resonators and the filter exhibits a high rejection in stopband by adopting the tapered DGS. Moreover, an inductance feed back between the output and input is introduced to produce transmission zeros. Filter with size of λ₀ /12 × λ₀ /12 × h (λ₀ is the wavelength at the midband frequency; h is the substrate height) is designed, fabricated and measured. The measured responses agree well with simulation results.