Dual-Band Complementary Split-Ring Resonator (CSRR) with High-Quality Factor and Its Applications in Low Phase Noise Oscillators and Small Multi-Band Diplexers and Filters

Low-Loss resonators with high Q factor have special importance in modern microwave telecommunications systems. In this paper, a modern dual-band CSRR with high Q factor is first examined using SIW technology on a surface waveguide. It should be noted that the proposed structure paves suitable way for emitting and propagating wave in two passing bands (approx. 4.7 and 5.3 GHz) below cutoff frequency waveguide. High Q factor and its high small-sized percentage is the salient specification of this structure as compared to other similar planar resonators proposed in various references. At the end of this paper, three applications of this resonator are studied in designing a small multiband filter with high Q factor, a small multi-band diplexer with low passage bandwidth and a planar oscillator with low-phase noise. According to the scientific literature, the proposed oscillator was found to enjoy the best performance at low phase noise for planar microwave oscillators.