Patch antenna and rectenna using the same
A patch antenna for receiving high frequency wireless signal and a rectenna using the same, more particularly, an impedance-matched patch antenna adopting a slot capacitive coupling structure and a rectenna capable of generating electrical energy from the wireless signals having different frequency band. A rectenna for receiving an A.C. wireless signal carrying electrical energy and converting the wireless signal into a D.C. electrical energy, is comprised of: a patch antenna for receiving the wireless signal comprising an dielectric substrate, a patch that is formed at the upper area of the surface of the dielectric substrate and providing the first frequency response characteristics, a ground plane formed on the other surface of the dielectric substrate, and an impedance matching means providing the second frequency response characteristics; and a rectifying unit that converts the wireless signal, received via the patch antenna, into a D.C. electrical energy by rectifying the wireless signal.
1. A patch antenna comprising:
an dielectric substrate;
a patch that is formed on a first surface of the dielectric substrate and provides a first frequency characteristics; and
a ground plane that is formed on a second surface of the dielectric substrate,
wherein an impedance matching means, that is capacitively coupled with the patch, is formed on one side of the ground plane;
wherein the impedance matching means is comprised of: a T-shaped slot formed in a bottom area of the ground plane; and a T-shaped feeder line formed inside of the T-shaped slot and being separated by a predetermined distance therefrom; and
wherein the T-shaped feeder line is formed at a location where a bar-shaped head of the T-shaped feeder line can face a bottom area of the patch so as to provide a second frequency characteristics by adjusting the size of the T-shaped slot and the T-shaped feeder line.
2. The patch antenna according to claim 1 , wherein the patch is a hexagonal shape formed by etching off two facing corners of a square.
3. A rectenna for receiving an A.C. wireless signal carrying electrical energy, and converting the wireless signal into a D.C. electrical energy, comprising:
a patch antenna for receiving the wireless signal comprised of a dielectric substrate, a patch that is formed at an upper area of one surface of the dielectric substrate and provides a first frequency response characteristics, a ground plane formed on the other surface of the dielectric substrate, and an impedance matching means that provides a second frequency response characteristics; and
a rectifying unit for converting the wireless signal, received via the patch antenna, into a D.C. electrical energy by rectifying the wireless signal,
wherein the rectifying unit is comprised of a voltage multiplying circuit that comprises at least one capacitor and diode and at least two of serially connected rectifying and multiplying stages capable of storing energy temporarily so as to convert the wireless signal into an electrical energy by rectifying the wireless signal and multiply the voltage of the converted electrical energy simultaneously.
4. The patch antenna according to claim 3 , wherein the rectifying unit is further comprised of:
a grounding area that is being separated from the ground plane of the patch antenna; and a bead that is located between the grounding area and the ground plane of the patch antenna for suppressing the effect of the A.C. signal.