Design and Studies of Bandstop Filters Using Modified CSRR DGS for WLAN Applications

In this paper, various dumbbell-shaped defected ground structure (DB-DGS) are compared with complementary split ring resonator DB-DGS which has sharp roll-off factor; as compared to other DB-DGS and a one pole bandstop filter with modified complementary split ring resonator (CSRR), DB-DGS has been proposed with compact size 0.12λ × 0.28λ and low return loss in passband at 2.4 GHz. The proposed filter is fabricated and measured with insertion loss of −28 dB in stopband and −0.8 dB return loss.