New dual-band bandpass filters with compact coupling and sizes reduction are proposed by using split ring stepped-impedance resonators and two paths coupling. In the new design, split ring SIR and defected ground structure are applied not only to reduce filter size but also to improve the filter performances. The presented filters have advantages of compact and novel structures, miniaturization and dual-band with nicer performances such as high selectivity, low passband insertion losses and so on, and these performances are demonstrated by measurement. The new design may be quite useful in wireless communication systems.
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