Abstract
In this article, the concept, analysis, and design of a substrate integrated waveguide (SIW) leaky-wave antenna incorporating a graphene ribbon for millimeter-wave operation are presented. It is demonstrated that the SIW supports a leaky mode when the graphene ribbon forming its broad wall is biased with an appropriate DC voltage. Unlike conventional sinusoidally modulated graphene leaky-wave antennas (LWAs), the proposed structure features a uniform configuration and operates using a single bias voltage that controls its propagation constant. Using the transverse equivalent technique, the propagation constant and frequency-scanning behavior are characterized. Moreover, the proposed graphene-based SIW LWA provides fixed-beam radiation suitable for point-to-point communication. Based on this structure and the developed analytical model, an LWA with fixed-beam capability is designed and verified through simulation, exhibiting a 28.5% squint-free bandwidth that makes it well-suited for high-speed wireless applications.