Planar Array with Optimized Perimeter Elements

Abstract

To effectively detect the targets in any direction, the radar antenna should be in the form of a planar array that has a large number of elements. In such a case, partially adaptive planar arrays, where only a few elements are adaptive, are often necessary to reduce the system's cost and increase the speed of the tracking capability. In this paper, only the perimeter elements of the planar arrays are selected to be adaptive while maintaining the good radiation characteristics as that of the fully adaptive planar arrays with, of course, lower cost and fewer RF components. Unlike a previous method that consists of optimizing only two edge elements in the linear arrays, the proposed planar array with optimized perimeter elements is quite sufficient to provide enough degrees of freedom to control the sidelobe pattern and place the desired nulls efficiently. Simulation results show that the required radiation pattern with asymmetric sidelobes and desired nulls can be obtained by optimizing only the perimeter elements of the planar arrays, while the interior elements are left unchanged.

Analysis of Performance Improvement of Planar Antenna Arrays With Optimized Square Rings for Massive MIMO Applications

“…Other researchers suggested the use of the phase-only excitation method [9] to optimize the planar array elements. Recently, efficient methods for linear [10][11][12][13][14] and planar arrays [15][16][17][18] were suggested. In these methods only the side elements of the linear or planar arrays were adjusted during the optimization process to reach the required power pattern with desired nulls and sidelobe levels.…”

“…In these methods only the side elements of the linear or planar arrays were adjusted during the optimization process to reach the required power pattern with desired nulls and sidelobe levels. In all of the methods that were presented in [10][11][12][13][14][15][16][17][18], the total number of the adjustable side-elements was chosen beforehand at a certain value. Thus, the optimized power patterns were found satisfactory only when there are sufficient numbers of the adjustable elements to fulfill the required constraints.…”

“…The element excitations in terms of either amplitudes or phases of the outer sub-planar array are made adjustable and they are optimized to form the desired power pattern. In contrast to the previous methods [10][11][12][13][14][15][16][17][18], the number of the adjustable side-elements in the outer square rings is also made adaptive. This means that the optimization algorithm will optimally choose the required number of the adjustable outer-square rings.…”