Ultra-broad-band MIMO array with steerable spotlight beams

This paper introduces concept of an ultra-broad-band cellular phased array with multiple steerable spotlight beams. The proposed array produces multiple 65-degree coverage beams and multiple steerable “spotlight” beams (HPBW<;14deg) for cellular MIMO coverage with hot-spots or small-cell enhancement. The spotlight beams can be steered electronically both in azimuth and elevation directions to provide mobile cellular services at high-demand “hot-spot” areas where high capacity service is required. These spotlight beams may also be used to fill voids or deficiencies caused by regular coverage beams, or to create a small-cell region within the coverage area. The proposed array uses ultra-broad-band aperture-couple patch providing over 45% frequency bandwidth from 1700 MHz to 2700 MHz, covering both the UMTS and LTE 2.5 bands.