Novel dual-band dual-prototype bandpass filter

This article presents the novel dual-band dual-prototype bandpass filter. The corresponding lowpass prototypes of the first and second passbands of the proposed filter are controllable and can be specified to be different at the outset. The dual-band resonator is realized by trisection stepped-impedance resonator. The dual-band inverter is implemented by stepped-impedance admittance inverter which can satisfy two different admittance values to realize two different frequency responses at two passbands. To compare and make more obvious the two passbands with two different lowpass prototypes, the proposed filter is illustrated with the Chebyshev 0.5db lowpass prototype for its first band and the Chebyshev 0.1db lowpass prototype for its second band. (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1496-1498, 2014