A miniature stripline filter with a wide stop band

The design of a miniature three-conductor stripline resonator on a double-layer dielectric substrate is suggested. Based on the proposed resonator diminutive bandpass filters with a wide stop band and high rejection is developed. To demonstrate characteristics of the proposed design the prototype of the fourth-order bandpass filter is fabricated. A stop band cutoff frequency of the filter at the level of -100 dB is more than 10 times higher than the central frequency of passband.