Synthesis of sub-arrayed monopulse linear arrays through matching of independently optimum sum and difference excitations

Optimization of difference pattern features in sub-arrayed monopulse antennas through and excitations matching procedure

“…In order to show the effectiveness of the proposed approach, let us consider two test cases described in [5] and in [9] and concerned with the minimization of the SLL and the maximization of the directivity, respectively. Both cases deal with an array of elements 20 = N 2 / λ -spaced and 3 = Q sub-arrays.…”

“…Nevertheless, the presence of independent feed networks is usually unacceptable because the complexity of the electronic circuit, the costs, and the arising electromagnetic interferences. In order to overcome such drawbacks, McNamara proposed in [5] a compromise solution where the sum pattern is generated by a set of excitation coefficients analytically computed, while the difference pattern is generated through sub-arraying. Towards this end, the array elements are grouped in different subsets and a weight is associated to each of them.…”

“…In order to solve such a problem, different approaches have been proposed. Analytically technique [5] (Excitation Matching Method EMM), or optimization approaches [6] [7] or hybrid approaches [8]. Whatever the method, the attention has been mainly focused on the searching of the pattern with the lower SLL.…”

Directivity Optimization in Planar Sub-Arrayed Monopulse Antenna

“…Since the available space is limited and because of the need of simple feed networks, an ever growing interest has been devoted to subarraying strategies [4][5][6][7][8][9]. In such a case, a set of excitations (either the sum or one difference) is fixed to the optimum, while the others are obtained by clustering the array elements into sub-arrays and weighting each of them.…”

“…To obtain good radar performances, the compromise solution should guarantee narrow beamwidth and low sidelobe levels (SLLs), high directivity, and deep normalized slope at boresight. Unfortunately, such requirements are incommensurable and the synthesis of compromise solutions has usually dealt with only the minimization of the SLLs [4][5][6][7][8][9][10] for a given beamwidth. Other studies concerned with linear arrays have also considered the maximization of the directivity [11].…”