Radiation characteristics of a 2D periodic slot leaky-wave antenna

The leaky-wave antenna (LWA) under consideration consists of a planar periodic slot array on top of a grounded substrate. The antenna is excited by an infinitesimal horizontal electric dipole. The antenna can produce either a pencil beam at broadside or a scanned conical beam. Increasing the substrate thickness causes the beam to scan towards endfire. The radiation characteristics of a complimentary LWA (using metal patches instead of slots) were discussed in a previous paper (see Zhao, T. et al., IEEE AP-S, vol 3, p.260-3, 2001). For the patch array it was determined that the substrate thickness controls the beam angle, while the patch size determines the beam width. The design principle for determining the substrate thickness is the same for both the slot and patch structures (see Zhao et al., 2001; Jackson, D.R. et al., IEEE Trans. Antennas and Propagation, vol.AP-41, p.344-8, 1993). For the slot array it is shown that the beam width can be controlled by adjusting the slot dimensions. Comparisons between the patch and slot configurations are made.