Least Perturbation Based Method of Multi-Objective Null Placement in Linear Antenna Array Using Evolutionary Algorithms

. The paper proposes a novel least perturbation based method of constrained null placement for a non-uniformly excited linear antenna array. Synthesis of amplitude and phase of edge element using least perturbation based analytical technique for required null placement leads to degradation of pattern in terms of increased side lobe level and beam broadening. Further computation capability of the method of least perturbation has been enhanced using an evolutionary algorithm. Subsequently, suitable evolutionary algorithms have been employed to find the optimum value of excitation and phase of edge elements subject to constraints of side lobe level reduction, beamwidth narrowing, and main beam control. Design of 8 and 15 elements linear array with a 95% reduction in computation time elucidates the capabilities of the proposed method. Further 3D electromagnetic solver-based validation process has been used to ascertain the practical acceptability of the method.