Multilayer meander parallel coupled-line microstrip bandpass filter

In this paper, a new method is presented to reduce the size of filter using multilayer, bend and MEMS technology. A three-pole coupled line bandpass filter with microstrip configuration is proposed. Usually, the tiny space of the coupled lines is troublesome in parallel coupled line filter in high frequency. Multilayer technology enables the tiny space fabricated. Therefore the total size is miniaturized. And the meander plays an important role in this filter. It should increase the inductance shown below. As the inductance deceases, the line length should be lengthened. In this, the effect of the inductance is considered. This meander gets the space gain. A design method for the proposed coupled-line filter is based on the coupled line theory, multilayer and meander. The experimental results show excellent agreements with theoretical simulation results. Also the proposed filter suppresses the 2^nd harmonic term and shows more sharpened skirt characteristic.