BANDPASS-FILTERS USING MICROSTRIP LINEAR TAPERED TRANSMISSION-LINE RESONATORS

This paper describes bandpass filters using linear tapered transmissio n line resonators (LTLR's). Bandpass filters are designed on the basis of the approximate description of LTLR's with cascaded multi-sections of uniform transmission lines whose widths are slightly different. By this design method, the fundamental characteristics of LTLR's and fil ter design parameters can be easily obtained using a general-purpose m icrowave circuit simulator. Trial LTLR bandpass filters showed excelle nt performance such as low insertion losses and the ability to control spurious responses, then their measured responses indicated close cor respondence with the design results.