Antenna capacitance for energy storage

1. An apparatus, comprising

a device for wireless communications, comprising:

an antenna;

an electronic circuit coupled to the antenna;

a power harvesting circuit coupled to the antenna, the power harvesting circuit to obtain electrical energy from a power source;

wherein the antenna is operable as a capacitor to store at least a portion of the electrical energy harvested by the power harvesting circuit, and to provide at least a portion of the stored electrical energy as operating power to the electronic circuit.

2. The apparatus of claim 1 , wherein the antenna comprises a dipole antenna.

3. The apparatus of claim 1 , wherein an element of the antenna comprises two layers of conductive material separated by a dielectric material.

4. The apparatus of claim 3 , wherein the antenna comprises capacitive coupling between the element and an antenna input of the electronic circuit.

5. The apparatus of claim 1 , wherein the electronic circuit is part of a radio frequency identification (RFID) tag.

6. The apparatus of claim 5 , further comprising an object connected to the RFID tag, the object to be identified by an identification number contained in the RFID tag circuit.

7. An apparatus, comprising

an antenna assembly for connection to a device for wireless communications, the antenna assembly comprising:

a first antenna element having a dielectric material between a first electrical conductor and a second electrical conductor to form a first electrical capacitor to store electrical energy to operate the device;

a first set of electrical contacts to couple a radio frequency (RF) signal from the first antenna element to a set of antenna connections of the device; and

a second set of electrical contacts to couple the first electrical capacitor to a set of power connections of the device.

8. The apparatus of claim 7 , further comprising a second antenna element having a dielectric material between a third electrical conductor and a fourth electrical conductor to form a second electrical capacitor to store the electrical energy to operate the device.

9. The apparatus of claim 7 , wherein the antenna assembly further comprises a balun transformer to match an impedance of the antenna assembly to an impedance of the device.

10. The apparatus of claim 7 , wherein the antenna assembly further comprises a capacitor circuit to block direct current from draining from the first electrical capacitor to the first set of electrical contacts.

11. The apparatus of claim 7 , wherein the first antenna element comprises multiple layers of the first conductor interspersed between multiple layers of the second conductor, with the dielectric material between the multiple layers of the first conductor and the multiple layers of the second conductor.

12. The apparatus of claim 7 , wherein the device is to include a radio frequency identification (RFID) tag circuit.

13. The apparatus of claim 7 , further comprising a RFID tag circuit coupled to the antenna assembly.

14. A method, comprising:

receiving electrical energy from a power generating source;

storing at least a portion of the received electrical energy in an antenna element configured as a capacitor; and

providing at least a portion of the stored electrical energy as electrical power to operate circuitry that controls wireless communications through the antenna.

15. The method of claim 14 , wherein all operating power for the circuitry is obtained from said receiving, said storing, and said providing.

16. The method of claim 14 , wherein said receiving comprises receiving the electrical energy from a power generating source that does not include a battery.

17. The method of claim 16 , wherein:

said receiving comprises receiving the electrical energy as radio frequency signals through the antenna; and

said providing comprises providing the stored electrical energy to a radio frequency identification (RFID) tag circuit.