Microstrip Dual-band Filter Research Articles

A simple and effective method for microstrip dual-band filters design

A new type of novel low loss dual-band microstrip filters using folded open-loop ring resonators (OLRRs) is presented in this letter. Both magnetic and electric coupling structures are implemented to provide high performance passband response. The first passband and second passband of the designed dual-band filter can be easily and accurately shifted to a desired frequency band by adjusting the physical dimensions of OLRRs. Finally, the 2.4-GHz/5.7-GHz and 2.4-GHz/5.2-GHz dual-band filters are illustrated and measured in this letter.

Concurrent dual band filter using single set of microstrip open-loop resonators

A concurrent dual band microstrip filter using only a single set of open-loop resonators is proposed. Each design parameter of the filter is controlled by two physical parameters and the specifications of the two bands can be met simultaneously. The filter can be designed by the traditional procedure of a single band filter.