▎ 摘　　要

The dispersive properties of the first higher order (EH1) mode in uniform graphene nanoribbons over a ground plane are numerically studied to point out the characteristics of the bound-mode and leaky-mode regimes. The graphene nanoribbon is then suitably designed to operate on the EH1 mode as a frequency-scannable leaky-wave antenna in both the millimeter and terahertz ranges.