The geometry of the proposed
CPW-fed split-ring rectangular slot antenna [15] is shown in
Fig. 1, the dimension of antenna in width (W) = 50 mm, the
length (L) = 50 mm, the width (Wf) = 6 mm, the length of
transmission line (Lf) = 13.5 mm, the length of ground (Ll) =
31.5 mm, the width of ground (WI) = 40 mm, the length of
rectangular tuning stub (Ls) = 16 mm, the width of rectangular
tuning stub (Ws) = 23 mm, the width of split-ring tuning stub
(WS1=WSZ) = 1.5 mm, the width of split-ring (SI=S2) = 1.5
mm, the slot rectangular tuning stub (S) = 4.5 mm, and the
slot between ground and CPW-fed line (g) = 0.5 mm.