SUPPRESSION OF SPURIOUS RESPONSES IN MICROSTRIP HALF-WAVELENGTH FILTERS COMBINING STAGGER TUNING AND RESISTIVE ATTENUATION

摘要

Stagger tuning and resistive attenuation are combined to attenuate harmonic responses of microstrip filters with half-wavelength resonators, extending the technique previously used for quarter-wave resonators. In a measured filter with 0.93 GHz center frequency and 22% bandwidth, the worst spurious peak between 1.3 and 2.7 GHz is about 10 dB better than with stagger tuning alone, while the next two peaks at 2.75 and 3 GHz are suppressed by a further 5 dB. (C) 2016 Wiley Periodicals, Inc. View this article online at wileyonlinelibrary.com.