Efecto Talbot espacio-temporal basado en CRLH LWAs: fundamentos y validación experimental

Abstract

A tunable spatio-temporal Talbot imaging phenomenon, based on metamaterial composite right/left-handed (CRLH) leaky-wave antennas (LWAs), is presented. This phenomenon, reported for the first time in the microwave domain, is based on the combination of the conventional spatial monochromatic Talbot effect and the transient (polychromatic) character of the pulse radiation phenomenon in the LWA structure. When the elements of a periodic CRLH LWA array are fed simultaneously by an input pulse, the spatial beams corresponding to different temporal frequencies constructively interfere in space so as to form a self-imaged pattern constituted by narrow Talbot zones. This Talbot effect is spatial-temporal since the Talbot zones are localized both in space and time. Furthermore, the scanning law property of the LWA is exploited to provide an off-axis radiation, leading to a tunable Talbot distance. This phenomenon is analyzed theoretically, numerically validated and experimentally demonstrated for the case of narrow-band pulses