Sector beam synthesis for cellular systems using phased antenna arrays

Cell sectorization is used extensively to increase the capacity of cellular systems; however, intersector interference caused by nonideal sector antennas limits full realization of sectorization benefits. We propose a new technique for sector beam synthesis using phased antenna arrays. We adopt the criterion of minimizing intersector interference, subject to a peak-to-peak ripple constraint on the in-sector power pattern. Spectral factorization permits a reparameterization yielding an easily solved fractional linear program. The proposed procedure accommodates nonisotropic antenna elements, arbitrary element sparing, and arbitrary sector boundaries, but is limited to uniformly spaced linear arrays. To demonstrate the utility of the proposed method, it is used to predict antenna array size requirements for a direct-sequence code-division multiple-access (DS-CDMA) cellular system