摘要 |
A gain-optimized, compact helical antenna array comprises an array of tapered pitch angle helical antenna elements. By tapered pitch angle is meant that the pitch angle increases from the base end of the antenna element to the distal end, in a manner that optimizes the gain of each helical element relative to helix length for a given physical size of the winding. Each helical winding is coupled to a signal distribution network, through which the antenna's radiation pattern is controllably defined. The antenna elements have a spatially aperiodic distribution, that reduces grating lobes, by minimizing the number of antenna elements which share the same azimuth. A radial line orthogonal to the boresight axis will intercept a minimum number of helical antenna elements of the array. To minimize mutual coupling, the mutual spacing between any two antenna elements of the array is at least a prescribed minimum separation that is proportional to a product of the square root of the gain of the respective antenna element and the wavelength of the operating frequency of the array.
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