A Miniature Bandpass filter with split ring resonator and asymmetrical coupled lines

The use of asymmetric coupled lines realizing the method to miniaturize a bandpass filter with equal capacitive, which has the advantages of low cost and simplicity. Furthermore, by adding the split ring resonator (SRR) what obtain magnetic coupling with transmission line that can mitigate frequency parasitic parameters and the parasitic inductance. These two applied methods overcome the limitation of previous research methods to achieve the improved performances and a higher operating frequency. As a result, the Miniature Bandpass filter achieves the maximum insertion loss is -1.66 dB in the frequency band of proposed filter between 5.16 GHz and 5.4 GHz. And return loss is more than 10 dB. Stop band rejection is more than 25 dB until 7.4 GHz.