Focus-Scanning Leaky-Wave Antenna With Electronically Pattern-Tunable Scatterers

A focus-scanning leaky-wave antenna is proposed. It is based on evanescent wave scattering by electronically pattern tunable scatterers fabricated of fine cascade connections of field effect transistors (FETs). The focus is tailored by switching the FETs so that numbers of the scattered waves cause constructive interference at the target point. Our prototype achieved focus-scanning at 2.4 GHz. The proposed antenna can be used as a very low-cost and lightweight phased array especially suitable to indoor use.