A nonuniform array of slots in the broad-walls of rectangular waveguides partially filled with dielectric slabs
This article describes a new nonuniform slot antenna array in the broad wall of rectangular waveguides partially filled with a dielectric slab. The slot elements are nonuniformly spaced to achieve a higher side lobe level while the amplitude and phase of their excitations are identical. Each slot element is fed by one dielectric-loaded rectangular waveguide with one end shorted for structural simplicity. Experimental results for an 8-element linear slot array operating at X-band show that the side lobe level is 15 dB over a frequency range from 9.5 GHz to 10.5 GHz. The simulated side lobe level can reach 20 dB for a 16-element linear array. Experimental results show that the side lobe level of a slot array can be improved using nonuniform element spacing without degrading the broadside radiation and gain. (C) 2008 Wiley Periodicals, Inc.
slot array dielectric-loaded waveguide slot antenna nonuniform spacing