Integrated Miniature PIFA with Artificial Magnetic Conductor Metamaterials

• US 20160020648A1
• Filed: 07/21/2014
• Published: 01/21/2016
• Est. Priority Date: 07/21/2014
• Status: Active Grant

• Current Assignee: Energous Corporation
• Original Assignee: Energous Corporation
• Inventors: Contopanagos, Harry
• Granted Patent: US 9,871,301 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/273 Adaptation for carrying or wearing by persons or animals
• 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 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 15/0006 Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices H01Q15/12, H01Q15/22, H01Q15/24 take precedence
• CPC Class Codes: H01Q 15/006 Selective devices having photonic band gap materials or materials of which the material properties are frequency dependent, e.g. perforated substrates, high-impedance surfaces
• CPC Class Codes: H01Q 19/10 using reflecting surfaces
• CPC Class Codes: H01Q 19/185 wherein the surfaces are plane
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence
• 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 50/23 characterised by the type of transmitting antennas, e.g. directional array antennas or Yagi antennas
• 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

Integrated antenna structures described herein may include planar inverted-F antennas (PIFAs) integrated with artificial magnetic conductor (AMC) metamaterials. The integrated metamaterial operatively coupled with the PIFA may function as an artificial magnetic reflector, sending all the energy radiated upwards, and thereby changing the original omnidirectional radiation pattern of the PIFA to a directional radiation pattern. The integrated antenna structures that include PIFAs and metamaterials may maintain a smaller form factor as compared to similar directional antennas, while exhibiting a suitable performance in terms of radiation efficiency, radiation pattern and impedance bandwidth.

Claims

1. An antenna structure, comprising:

a printed circuit board (PCB);

at least one planar inverted-F antenna (PIFA), configured within a top and bottom layer of the PCB; and

at least one artificial magnetic conductor (AMC) cell configured within the PCB, the at least one AMC cell comprising a backing metal layer arranged in a first inner layer of the PCB, and an AMC metal layer formed in a second inner layer of the PCB, the AMC metal layer being configured to have a predetermined shape,

wherein the AMC metal layer is configured to reflect energy radiated by the PIFA.

2. The antenna structure of claim 1, wherein the predetermined shape of the AMC metal layer comprises a square θ

ring shape.

3. The antenna structure of claim 1, wherein the predetermined shape of the AMC metal layer comprises a square ring shape.

4. The antenna structure of claim 1, wherein the AMC metal layer is configured to reflect energy radiated by the PFIA in a directional radiation pattern.

5. The antenna structure of claim 1, wherein the AMC metal layer comprises metamaterial.

6. The antenna structure of claim 1, wherein the at least one PIFA comprises

an antenna element, configured over a first portion of the top layer of the PCB, the antenna element comprising one or more antenna slots,

a ground element formed over a first portion of a bottom layer of the PCB, wherein the antenna element is coupled to the ground element and a second portion of the bottom layer of the PCB using a first ground via and a signal via, respectively, and

a folded ground formed over a second portion of the top layer of the PCB, the folded ground being coupled to a third portion of the ground element using one or more second ground vias.

7. The antenna structure of claim 6, wherein the ground element comprises a ground slot.

8. The antenna structure of claim 6, wherein the top layer and bottom layer comprise a conductive metal.

9. The antenna structure of claim 1, further comprising a transmitter, operatively coupled to the at least one PFID, the transmitter being configured to provide a signal for radiation by the PFID.

10. The antenna structure of claim 9, the transmitter comprising a processing apparatus for adjusting at least one of a phase and magnitude of the signal.

11. An apparatus for providing 3-dimensional pockets of energy using pocket-forming, comprising:

at least one printed circuit board (PCB);

a plurality of planar inverted-F antennas (PIFA), each configured within a top and bottom layer of the at least one PCB; and

a plurality of artificial magnetic conductor (AMC) cells configured within the at least one PCB, each of the plurality of AMC cells comprising a backing metal layer arranged in a first inner layer of the at least one PCB, and an AMC metal layer formed in a second inner layer of the at least one PCB, the AMC metal layer being configured to have a predetermined shape,

wherein the AMC metal layers are configured to reflect energy independently radiated by each of the PIFAs to enable pocket-forming of energy.

12. The apparatus of claim 11, wherein the predetermined shape of the AMC metal layer comprises a square θ

ring shape.

13. The apparatus of claim 11, wherein the predetermined shape of the AMC metal layer comprises a square ring shape.

14. The apparatus of claim 11, wherein the AMC metal layer is configured to reflect energy radiated by the PFIA in a directional radiation pattern.

15. The apparatus of claim 11, wherein the AMC metal layer comprises metamaterial.

16. The apparatus of claim 11, wherein each of the PIFAs comprises an antenna element, configured over a first portion of the top layer of the PCB, the antenna element comprising one or more antenna slots,

a ground element formed over a first portion of a bottom layer of the PCB, wherein the antenna element is coupled to the ground element and a second portion of the bottom layer of the PCB using a first ground via and a signal via, respectively, and

a folded ground formed over a second portion of the top layer of the PCB, the folded ground being coupled to a third portion of the ground element using one or more second ground vias.

17. The apparatus of claim 16, wherein the ground element comprises a ground slot.

18. The apparatus of claim 16, wherein the top layer and bottom layer comprise a conductive metal.

19. The apparatus of claim 11, further comprising a transmitter, operatively coupled to the at least one PFID, the transmitter being configured to provide a signal for radiation by the PFID.

20. The apparatus of claim 19, the transmitter comprising a processing apparatus for adjusting at least one of a phase and magnitude of the signal.

21. A cell arrangement, comprising:

a artificial magnetic conductor (AMC) cell, the AMC cell arranged in a multi-layer printed circuit board (PCB), the AMC cell comprising a plurality of edges and further comprising;

a backing metal layer arranged in a first inner layer of the PCB;

at least one planar inverted-F antenna (PIFA), configured within a top and bottom layer of the PCB; and

an AMC metal layer formed in a second inner layer of the PCB, the AMC metal layer comprising metamaterial and configured to have a predetermined shape.

22. The cell arrangement of claim 21, wherein the backing metal layer is not coincident with at least one of the plurality of edges.

23. The cell arrangement of claim 21, wherein the predetermined shape of the AMC metal layer comprises a square θ

ring shape.

24. The cell arrangement of claim 21, wherein the predetermined shape of the AMC metal layer comprises a square ring shape.

25. The cell arrangement of claim 21, wherein the matamaterial is tuned to a resonant frequency that is at a low end of a desired frequency band.

26. The cell arrangement of claim 21, wherein the PIFA further comprises:

an antenna element, configured over a first portion of a top layer of the PCB, the antenna element comprising one or more antenna slots,

a ground element formed over a first portion of a bottom layer of the PCB, wherein the antenna element is coupled to the ground element and a second portion of the bottom layer of the PCB using a first ground via and a signal via, respectively, and

a folded ground formed over a second portion of the top layer of the PCB, the folded ground being coupled to a third portion of the ground element using one or more second ground vias.

27. The cell arrangement of claim 26, wherein the AMC metal layer is configured to reflect energy radiated by the PIFA.

28. The cell arrangement of claim 27, wherein the AMC metal layer is configured to reflect energy radiated by the PFIA in a directional radiation pattern.