Stopband characteristics of complementary triangular split ring resonator loaded microstrip line

A miniaturized complementary triangular split ring resonator (CTSRR) is proposed to provide a peak rejection of -35dB in the transmission characteristics. An equivalent circuit is generated to accurately predict the resonant frequency of the resonator. Miniaturization is achieved by optimizing the spacing between the split rings. The area of CTSRR is 21% less than that of the circular SRR and 42.7% less than that of the square SRR. To demonstrate the stopband and negative permittivity characteristics, a right handed microstrip line is loaded with three CTSRR unit cells. Measured S-parameters exhibit a stopband from 4.17GHz to 4.83GHz with negative extracted permittivity over a frequency range from 4.17GHz to 4.68GHz. A peak value of ε_eff =-4.5 is extracted. The extracted permeability shows positive values in the frequency range corresponding to the negative permittivity band confirming single negative material.