Novel cross-coupled filters using metamaterial split ring resonators

In this paper, a novel metamaterial (MTM) split ring resonators for microwave bandpass filter is proposed. The effective permittivity and permeability of the filter are extracted. The extracted results show that the effective permittivity and permeability are both positive at the first half of passband and they are negative at the other part. The double positive or double negative characteristic enables the transmission of electromagnetic wave in-band while the single negative characteristic disables the transmission out-of-band. The theory of metamaterial and the NRW (Nicolson-Ross-Weir) approach to verify its double negative characteristics are briefly introduced. From the simulation results one can see that the filter has advantages of small dimension, low in-band insertion loss and good out-of-band suppressed and linearity.