RF energy harvesting with multiple antennas in the same space

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Abstract
It is highly desirable to increase the amount of energy derived from a given space by an energy-harvesting device. In this paper, multiple energy-harvesting antennas in essentially one space or area are proposed and experimentally studied as a means to increase the energy or power/area ratio. Four cooperating antennas are proposed in a square area that is less than twice the area required for a single antenna. The results obtained suggest that this can be a very promising method for energy harvesting.