Dual-Band and Dual-Polarized Leaky-Wave Antenna Based on Slotted SIW

A dual-band and dual-polarized leaky-wave antenna excited by slotted substrate integrated waveguide (SIW) is proposed in this letter. Periodic transverse slots are etched on the top plane of SIW, interrupting the current flow, and hence, achieving linearly-polarized leaky-mode radiation. Meanwhile, a slow-wave mode of slotted SIW is excited at high frequencies, and loading periodic circular slots on the bottom plane converts the slow-wave mode to a fast-wave mode. It shows that this higher frequency band exhibits a left-hand circularly polarized radiation. The measured results validate that the proposed antenna has two operational frequency bands, 9.0–10.7 GHz for linearly polarized radiation ( $|S_{11}|  dB) and 13.4–16.2 GHz for circularly polarized radiation ( $|S_{11}| dB and antireflection $ 3.2), and achieves beam scanning from $+107^{\circ }$ to $+167^{\circ }$ (upper space) at the lower frequency band and from $-41^{\circ }$ to $-114^{\circ }$ (lower space) at the higher band.