Leaky-mode dispersion analysis in parallel-plate waveguides loaded with FSS and AMC with application to 1D leaky-wave antennas

Abstract

Partially Reflecting Surface (PRS) antennas have attracted considerable interest in recent years due to their ability to conceive high-directivity low-profile broadside 2D antennas with simple configurations [1–3]. On the other hand, 1D leaky-wave antennas (LWA) combining a waveguide and printed circuits have shown the ability to flexibly control the phase velocity and the radiation-rate of the leaky-mode, thus allowing to taper the radiation pattern to obtain different pointing angles, radiation efficiencies and sidelobes distribution [4–5]. In this contribution, we present a novel 1D LWA structure, composed by a parallel-plate waveguide (PPW) loaded with a Frequency Selective Surface (FSS) and an Artificial Magnetic Conductor (AMC), as shown in Fig.1-a. This novel type of 1D LWA provides an interesting mechanism to control the radiation properties of TE leaky-modes. This structure offers a different mechanism to control the leaky-waves from the one proposed in [4–5], and it is extensible to 2D PRS-LWA [1–3]. The top FSS acts as a PRS, controlling with its reflection magnitude the level of the leakage-rate associated to the leaky-mode. On the other hand, the reflection phase of the bottom AMC will determine the pointing angle of the leaky-mode.