Broadside linear array of resonant type leaky-wave antenna composed of image NRD guide

A broadside linear array of a resonant-type leaky-wave antenna with a new construction based on an image nonradiating dielectric (NRD) guide is proposed. Fundamental characteristics are investigated by performing both the finite-difference time-domain (FDTD) analysis and basic experiments. The proposed configuration makes it possible to improve the H-plane pattern beamwidth, which is much wider than that of the E-plane. First, a single-element resonant-type leaky-wave antenna fed by a longitudinal slot on the broad wall of a rectangular waveguide is analysed to obtain the data used for the design of the linear array. Next, based on the results obtained, a 2-element linear array employing the same feeding technique as that of the single-element case is designed and analysed. The H-plane beamwidth is found to be 34°, which is 36° narrower than that of the single-element antenna. Finally, measured results are also presented to confirm the effective performance of the proposed configuration.