Compact and wideband DC bias line based on defected ground structure

摘要

In this paper, a technique using a novel cross-shaped defected ground structure (DGS) to broaden the operating bandwidth and reduce the size of a conventional DC bias line is proposed. The conventional DC bias line is composed of a λ/4 high impedance transmission line and a proper fan-shaped capacitor. Due to the slowwave characteristics introduced by the DGS, the original length of the λ/4 high impedance transmission line can be shortened while maintain the same electrical length. The experimental result shows that the proposed DC bias line has a much wider operating bandwidth than that of the conventional one by 153% and 83.3% of the initial λ/4 length.