Patent ID: 7956572

Claim:
A system for collecting radio frequency (RF) power, comprising: a power source comprising at least a first antenna element and a second antenna element, wherein each of said first and second antenna elements are coupled to at least one rectifier to form at least two rectenna elements, said power source converting the RF power into a direct current (DC) power source output power; a DC combining circuit associated with said power source, wherein said DC combining circuit is configured to dynamically combine said at least two rectenna elements in one of a plurality of series/parallel configurations; a controlled impedance power controller comprising: a power converter having a power converter input and configured to receive said DC power source output power at said power converter input, wherein said DC power source output power comprises current and voltage characteristics which may drift over time, wherein said power converter is configured to present a positive equivalent resistive load to said power source over a range of input power levels; and wherein said controlled impedance power controller is further configured to control said DC combining circuit such that said DC power source output power approaches a desired overall power output from said at least two rectenna elements; and an energy storage device configured to store said DC power source output power.