Compact Resonator Filters and Power Dividers Designed with Simplified Meta-Structures

Compact resonator filter and power divider are investigated and designed using a simplified meta-structure where the series capacitor in the conventional composite right/left-handed transmission-line (CRLH) structure is not required. The design is based on the resonant frequency of shunt microstrip inductor and capacitor connected to ground. The filter and power divider are fabricated and measurement results show good agreements with full-wave simulation results. The resonant frequency and bandwidth of the filter can be easily optimized from the physical sizes of unit cell. Different power levels at two output ports in the power divider are achieved by changing the length of coupling lines with negligible phase difference. Since the series capacitors are not required in the design, the proposed filters and power dividers have quite compact sizes.