A low loss beam forming method and antenna structure are disclosed. The method and structure may preferably be used in forming two narrow beams within a cellular sector. This method allows an increase in the overall network capacity by using a three-column non-planar array and a compact, low-cost, low-loss 3-to-2 Beam-Forming Network (BFN). This structure produces two symmetrical beams with respect to the azimuth boresight. Radiation patterns of the two beams are designed to cover the entire azimuth coverage angle of a cellular sector with minimum beam-split loss and cross-over losses.