Abstract In order to generate narrow beams with individual heights of sidelobes, we perform a synthesis of sum patterns. The side lobes can be adjusted to any arbitrary specification and flat top far field radiation patterns using Enhanced Flower Pollination Algorithm (EFPA) is presented in this paper. The problem of designing an array can be expressed as an optimization problem that aims to reduce the first two sidelobes to -50dB and by reducing the remaining sidelobes to -40dB. The EFPA is applied to determine the excitation coefficients of their amplitudes so as to obtain the required pattern. The objective for case 2 is to obtain the flat top sector beam for specified angular regions. Complex excitation coefficients are determined using EFPA for various beam widths. The radiation patterns are generated numerically using the obtained excitation coefficients. The results reveal that not only the ripples are controlled in the trade-in region, but also maintained sidelobe levels in the acceptable limits. The results presented are very much useful for marine radar applications.