Capacitively coupled resonators with wide tuning range have been proposed in coplanar waveguide (CPW) technology, based on the concept of electromagnetic bandgaps (EBGs). By loading the resonator with shunt-connected varactor diodes, the phase velocity of the line and, hence, the resonant frequency of the structure can be electrically controlled. Due to the slow-wave effect related to the presence of the varactors, a certain level of miniaturization is also achieved. Moreover, the frequency-selective properties of EBGs are used to reject the first spurious frequency of the resonators. © 2005 Wiley Periodicals, Inc.
- Coplanar waveguide (CPW)
- Electromagnetic bandgap (EBG)
- Microwave resonators
- Varactor diodes