Synthesis of Sparse or Thinned Linear and Planar Arrays Generating Reconfigurable Multiple Real Patterns by Iterative Linear Programming

Abstract

Abstract-It is shown in this paper that the problem of reducing the number of elements for multiplepattern arrays can be solved by a sequence of reweighted 1 optimizations under multiple linear constraints. To do so, conjugate symmetric excitations are assumed so that the upper and lower bounds for each pattern can be formulated as linear inequality constraints. In addition, we introduce an auxiliary variable for each element to define the common upper bound of both the real and imaginary parts of multiple excitations for different patterns, so that only linear inequality constraints are required. The objective function minimizes the reweighted 1 -norm of these auxiliary variables for all elements. Thus, the proposed method can be efficiently implemented by the iterative linear programming. For multiple desired patterns, the proposed method can select the common elements with multiple set of optimized amplitudes and phases, consequently reducing the number of elements. The radiation characteristics for each pattern, such as the mainlobe shape, response ripple, sidelobe level and nulling region, can be accurately controlled. Several synthesis examples for linear array, rectangular/triangular-grid and randomly spaced planar arrays are presented to validate the effectiveness of the proposed method in the reduction of the number of elements.

Unequal Polyomino Layers for Reduced SLL Arrays With Scanning Ability

“…These solutions are mainly applicable in designs requiring a limited angular field of view as well as in designing wide band array. Recently there has been a renewed interest in this area for various applications ranging from spaceborne to ground antennas, from civil to military systems [1][2][3][4][5]. The key point in an irregular lattice is that of having a non-periodic disposition of the phase centers of the elements of the array, with benefits in scanning capabilities and grating lobes suppression.…”

Circular-Ring Antenna Arrays Being at the Same Time Sparse, Isophoric, and Phase-Only Reconfigurable: Optimal Synthesis via Continuous Aperture Sources

“…Being at the same time isophoric and phase-only reconfigurable, the achieved solutions grant at the same time all the advantages of the antennas designed in [3,10,[22][23][24][25][26][27][28][29].…”

Shape Reconstruction via Equivalence Principles,constrained Inverse Source Problems and Sparsity Promotion

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