Abstract
This letter proposes a wideband compact DC block design technique. This DC block has a wide pass-band and wide stop-band and transforms termination impedances. It comprises a pair of coupled lines on a defected ground structure (DGS) with capacitor loading. A periodic DGS pattern increases coupling, and, consequently, a wideband DC block design is allowed with a microstrip process on a high dielectric low height substrate. A DC block with equal termination impedances of 50 Ω and another that transforms 50 into 30 Ω are fabricated. The measured fractional bandwidths are 48% and 47%. The size of the DC block is 16.8× 15 mm2(0.057λ0× 0.051λ0).
