The potentialities offered by antenna arrays make them very attractive for future communication systems. Recent channel measurement at millimeter-waves (mmWaves) have in fact shown that the angular dispersion of the interference follows specific distributions, which are often Gaussian. Accordingly, this paper proposes a phase-only synthesis algorithm for antenna arrays, able to generate patterns having Gaussian shaped nulls to properly suppress the interference. The developed method is suitable for arrays of arbitrary geometry and can operate in the three-dimensional (3D) scenario, thus performing zenith-azimuth synthesis. To prove the effectiveness of the proposed solutions, numerical results involving multi-ring arrays are presented.