INDIVIDUAL ANTENNA ELEMENT

• US 20160190868A1
• Filed: 12/29/2014
• Published: 06/30/2016
• Est. Priority Date: 12/29/2014
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Shuai Shao
• Inventors: Shao, Shuai, Gudan, Ken, Hull, Jonathan J.
• Granted Patent: US 10,862,200 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 21/065 Patch antenna array
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/27 characterised by the type of receiving antennas, e.g. rectennas
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas

Abstract

An individual antenna element is described. In one embodiment, the individual antenna element is a patch antenna which has an electrically small radiating element with a U-shaped slot on an antenna substrate, with a gain greater than 2 dBi with +/−45 degree coverage.

Claims

1. A patch antenna having an electrically small radiating element with a U-shaped slot on an antenna substrate, with a gain greater than 2 dB with +/−

45 degree coverage.

2. The patch antenna defined in claim 1 wherein the gain is greater than 3 dBi.

3. The patch antenna defined in claim 1 wherein coverage of the radiating element is +/−

50 degrees.

4. The patch antenna defined in claim 1 wherein an outer dimension of the U-shaped slot is within 0.16λ

×

0.16λ

.

5. The patch antenna defined in claim 1 wherein an outer dimension of the U-shaped slot is within 0.155λ

×

0.118λ

.

6. The patch antenna defined in claim 1 wherein the width of the U-shaped slot is at least 0.5 mm.

7. The patch antenna defined in claim 1 wherein the patch provides greater than 100 MHz bandwidth at the −

10 dB level.

8. The patch antenna defined in claim 1 wherein the radiating element is tuned to 2.4-2.5 GHz.

9. The patch antenna apparatus defined in claim 1 further comprising:

a ground plane covering a back side of the radiating element; and

a feeding network coupled to the radiating element.

10. A sensor node for use in a sensor network, the sensor comprising:

one or more sensors for sensing and logging data;

a transmitter to transmit information wirelessly;

a patch antenna having an electrically small radiating element with a U-shaped slot on an antenna substrate, with a gain greater than 2 dBi with +/−

45 degree coverage;

an energy harvesting unit coupled to the antenna apparatus and operable to convert incident energy received by the antenna apparatus to direct current (DC); and

a microcontroller coupled to the energy harvesting unit, the one or more sensors and the transmitter, the microcontroller operable to cause the transmitter to communicate sensed data from at least one of the one or more sensors while powered by energy previously harvested by the energy harvesting and storage unit.

11. The sensor node defined in claim 10 wherein the gain is greater than 3 dBi.

12. The sensor node defined in claim 10 wherein coverage of the radiating element is +/−

50 degrees.

13. The sensor node defined in claim 10 wherein an outer dimension of the U-shaped slot is within 0.16λ

×

0.16λ

.

14. The sensor node defined in claim 10 wherein width of the U-shaped slot is at least 0.5 mm.

15. The sensor node defined in claim 10 wherein the patch provides greater than 100 MHz bandwidth at the −

10 dB level.

16. The sensor node defined in claim 10 wherein the radiating element is tuned to 2.4-2.5 GHz.

17. A Wi-Fi communication system comprising:

an access point coupled to provide access to a network;

a sensor node comprising

one or more sensors for sensing and logging data;

a transmitter to transmit information wirelessly;

a patch antenna having an electrically small radiating element with a U-shaped slot on an antenna substrate, with a gain greater than 2 dBi with +/−

45 degree coverage;

an energy harvesting unit coupled to the antenna and operable to convert incident energy received by the antenna apparatus to direct current (DC); and

a microcontroller coupled to the energy harvesting unit, the one or more sensors and the transmitter, the microcontroller operable to cause the transmitter to communicate sensed data from at least one of the one or more sensors to the access point while powered by energy previously harvested by the energy harvesting and storage unit.

18. The communication system defined in claim 17 wherein the gain is greater than 3 dBi.

19. The communication system defined in claim 17 wherein coverage of the radiating element is +/−

50 degrees.

20. The communication system defined in claim 17 wherein an outer dimension of the U-shaped slot is within 0.16λ

×

0.16λ

.