Design and Analysis of Compact Microstrip Multiband Bandpass Filter Using U-shape with Triangular Stepped Impedance Resonators.

A new class of compact microstrip multiband bandpass using symmetric U-shape with triangular stepped impedance resonator is proposed for wireless application. The multiband filter only employs two symmetric U-shape with triangular stepped impedance resonator. By properly tuning the impedance ratios and length ratios of stepped impedance resonators, a multiband filter response can be achieved easily. Based on the similar characteristics of triangular shaped SIR, a miniaturized multiband band pass filter operating at the center frequencies (0.8GHz, 2.3GHz, 3.8GHz, 5.1GHz and 5.8GHz) are obtained. The filter is characterized by analyzing the filter parameters return loss and insertion loss. The numerical analysis of the proposed filter is derived by using commercially available electromagnetic simulation software IE3D. The results show that the filter has compact size, good return loss and insertion loss characteristics.