METAMATERIAL ANTENNA ARRAY WITH RADIATION PATTERN SHAPING AND BEAM SWITCHING

• US 20110026624A1
• Filed: 08/03/2010
• Published: 02/03/2011
• Est. Priority Date: 03/16/2007
• Status: Active Grant

• Current Assignee: Tyco Electronics Services GmbH (TE Connectivity Ltd. (United Kingdom))
• Original Assignee: Rayspan Corporation
• Inventors: Achour, Maha, Gummalla, Ajay, Poilasne, Gregory, Stoytchev, Marin
• Granted Patent: US 8,462,063 B2
• Time in Patent Office: Days
• US Class Current: 375/260
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 15/0086 said selective devices having materials with a synthesized negative refractive index, e.g. metamaterials or left-handed materials
• CPC Class Codes: H01Q 25/00 Antennas or antenna systems providing at least two radiating patterns arrangements for changing or varying the orientation or the shape of the directional pattern H01Q3/00
• CPC Class Codes: H01Q 3/30 varying the relative phase between the radiating elements of an array H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence

Abstract

Apparatus, systems and techniques for using composite left and right handed (CRLH) metamaterial (MTM) structure antenna elements and arrays to provide radiation pattern shaping and beam switching.

Claims

1. An antenna system, comprising:

a plurality of antenna elements, each antenna element configured to receive or transmit a radio signal and including a composite left and right handed (CRLH) structure;

a plurality of switching elements coupled to the plurality of antenna elements, each switching element activates at least one of the plurality of antenna elements in response to a switching control signal;

a radio frequency (RF) radio transceiver module coupled to the plurality of switching elements; and

a beam switching controller responsive to a feedback control signal from the RF radio transceiver module to produce the switching control signal, wherein the switching control signal initiates one of a plurality of operating modes, including a multiple input multiple output (MIMO) operation mode to find directions of multipath links and lock the plurality of antenna elements to generate antenna patterns in these directions.

2. A method of operating an antenna system comprising a plurality of antenna elements including a composite left and right handed (CRLH) structure, a RF radio transceiver module, a plurality of switching elements, and a beam switching controller configured to include a multiple input multiple output (MIMO) operation mode comprising the steps of:

receiving a feedback control signal at the beam switching controller;

generating a switching control signal from the beam switching controller based on the feedback control signal to lock the plurality of switching elements to at least one of the plurality of antenna elements to generate a MIMO multiple antenna pattern.

3. A method of initiating a switching configuration of a plurality of CRLH antenna elements comprising the steps of:

receiving a feedback control signal; and

generating a switching control based on the feedback control signal to lock a plurality of antenna switching elements to at least one of the plurality of composite left and right handed (CRLH) antenna elements such that multiple subsets of the antennas may operate simultaneously.

4. A method for shaping a radiation pattern of a plurality of composite left and right handed (CRLH) metamaterial (MTM) antenna elements that includes at least one electromagnetic bandgap (EBG) structure, the method comprising the step of shaping a substantially orthogonal radiation pattern.

5. A method of shaping radiation patterns and switching beams based on an antenna system comprising a plurality of antenna elements, comprising the steps of:

receiving at least one signal into a multiple input multiple output (MIMO) radio frequency (RF) radio transceiver from a main feed line;

splitting the at least one signal into a plurality of sub-signals;

transmitting each sub-signal on a dedicated path to one of a plurality of pattern shaping circuits;

shaping a radiation pattern associated with a subset of antenna elements by using the pattern shaping circuit that is coupled to the subset; and

activating at least one subset at a time to generate the radiation pattern associated with the at least one subset, wherein activation is switched among the subsets as time passes based on a predetermined control logic, wherein a composite left and right handed (CRLH) metamaterial (MTM) structure is used to form each of the antenna elements.

6. A communication system, comprising:

a ground electrode; and

an antenna structure, comprising

an input portion;

a radiating portion;

a capacitance element formed between the input portion and the radiating portion; and

a shunt inductive element coupled between the radiating portion and the ground electrode, the shunt inductive element forming a shunt inductance from the radiating portion to the ground electrode.

7. The communication system as in claim 6, wherein the antenna structure is a monopole antenna structure.

8. The communication system as in claim 6, wherein the capacitance element forms a series capacitance between the input portion and the radiating portion, and wherein the communication system forms a Composite Right/Left-Handed (CRLH) structure having the series capacitance and the shunt inductance.

9. The communication system as in claim 8, wherein the antenna structure is a printed conductive structure on a dielectric substrate.

10. The communication system as in claim 9, wherein the capacitance element is formed by a gap in the printed conductive structure between the input portion and the radiating portion of the antenna structure so as to form a capacitive coupling therebetween.

11. The communication system as in claim 8, wherein the ground electrode is isolated from the input portion of the antenna structure

12. The communication system as in claim 8, wherein the shunt inductive element comprises a conductive line.

13. The communication system as in claim 12, wherein the series capacitance has a corresponding series resonance frequency, and the shunt inductance has a corresponding shunt resonance frequency

14. The communication system as in claim 13, wherein the ground electrode is formed in a first substrate layer and the radiation portion of the antenna structure is formed in a second substrate layer separated from the first substrate layer by a dielectric layer, and wherein the ground electrode does not substantially overlap a footprint of the radiating portion of the antenna structure.

15. The communication system as in claim 13, wherein the dimensions and placement of the ground electrode, radiating portion, and shunt inductive element determine an operating bandwidth of the antenna structure.

16. The communication system as in claim 13, wherein the antenna structure has a first resonant frequency, and wherein the communication system has a plurality of resonant frequencies.

17. The communication system as in claim 16, wherein the dimensions and placement of the ground electrode, radiating portion, and shunt inductive element determine the shunt resonance frequency.

18. The communication system as in claim 6, wherein the dimensions and placement of the radiating portion and input portion determine the series resonance frequency.

19. The communication system as in claim 6, further comprising:

a plurality of antenna structures each coupled to at least one switching element,

wherein each switching element activates at least one of the plurality of antenna elements in response to a switching control signal, and

wherein the at least one switching element is further coupled to a Radio Frequency (RF) transceiver module.

20. The communication system as in claim 8, further comprising:

a pattern shaping circuit to supply a radiation transmission signal to the antenna structure, wherein the pattern shaping circuit splits a received signal into different antenna feed signals to create a radiation pattern.

21. The system as in claim 20, wherein the pattern shaping circuit generates an amplitude phase combination for each antenna of the antenna structure.

22. The system as in claim 20, wherein the phase shifting circuit comprises a transmission line structure having a series capacitance and a shunt inductance.

23. The system as in claim 22, wherein the phase shifting circuit is a directional coupler.

24. The system as in claim 23, wherein the directional coupler is a multi-port microwave directional coupler, and wherein the phase shifting circuit provides isolation between the plurality of antenna structures.

25. The system as in claim 24, wherein the directional coupler provides offset to at least one antenna feed signal so as to generate an orthogonal radiation pattern set to input portions of multiple antenna structures.

26. The system as in claim 22, wherein the phase shifting circuit comprises an electromagnetic band gap structure.

27. The communication system as in claim 20, further comprising:

a beam switching controller responsive to a feedback control signal from the RF transceiver module to produce the switching control signal,

wherein the switching control signal initiates one of a plurality of operating modes, including a Multiple Input Multiple Output (MIMO) operation mode to find directions of multipath links and lock the plurality of antenna elements to generate antenna patterns in these directions.

28. The communication system as in claim 27, wherein the pattern shaping circuit and the beam switching controller are configured to selectively direct at least one radiation transmission signal to at least one antenna structure at a time.