Fixed Frequency and Tunable Metamaterial-Based Ring Resonators with Narrowly Spaced Resonances

Metamaterial-based composite right/left-handed transmission lines are used in the design of fixed frequency and tunable ring resonators. Under specific design conditions, the first two resonant modes can be narrowly spaced. A simple passive band-pass filter is demonstrated at 2.92 GHz with a bandwidth of about 9% using this concept. This type of design is also used as a tunable resonator and a tuning range of 30% is demonstrated.