A 4-GHz 1:10 unequal Wilkinson power divider using split ring resonator

Power division is widely used in most wireless/wire line communication systems. However, the design of an unequal Wilkinson power divider, particularly with a large division ratio, becomes a challenge in engineering due to the difficulties in realization of the high or low-impedance transmission lines on a dielectric substrate. This paper presents the results of a compact 1:10 unequal Wilkinson power divider (WPD) fabricated using split ring resonator (SRR) and complementary split ring resonator (CSRR) etched in the back metal level (ground plane). The designed WPD is fabricated and measured at central frequency of 4 GHz, with a 294.9 Ω microstrip-line branch and a 29.5 Ω branch located in the circuit. The measurements of insertion and reflection losses of the fabricated circuit as well as the isolation between the output ports are in a good agreement with the simulated responses of the designed circuit. The measured performances show that the proposed 1:10 Wilkinson divider has excellent performances, dividing ratios of -1 to -1.3 dB and -11.1 to -11.7 dB at port 2 and port 3 over 3.8-4.2 Ghz.