Slotline Leaky Wave Antenna with a Stacked Substrate

Abstract

This paper presents a new version of a leaky wave antenna based on a conductor-backed slotline with a stacked substrate. The antenna radiates due to the first order space leaky wave excited on a slotline with a wide slot. The antenna radiates into the one main beam above the substrate. The main lobe of the radiation pattern is relatively wide and there is also intensive radiation in the backward direction and below the substrate. Shaping the background metal layer produces a reflector, which reduces the parasitic radiation by 7 dB. When this background layer is larger than the substrate the radiation below the substrate is additionally reduced by 3 dB. The reflector moreover reduces the width of the main beam.