MULTIPLE-INPUT-MULTIPLE-OUTPUT ANTENNA DEVICE

• US 20130242870A1
• Filed: 05/02/2013
• Published: 09/19/2013
• Est. Priority Date: 12/22/2009
• Status: Active Grant

• Current Assignee: Lite-On Technology Corporation
• Original Assignee: Lite-On Technology Corporation
• Inventors: SU, SAOU-WEN, TSAI, LIN-HAN, CHEN, CHUAN-HSING
• Granted Patent: US 9,444,530 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 3/242 Circumferential scanning
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems

Abstract

A Multiple-Input-Multiple-Output (MIMO) antenna device is adapted for connecting electrically to a radio frequency (RF) circuit for transmitting and receiving RF signals . The MIMO antenna device includes a circuit board, a plurality of antenna units, and a plurality of multiplexer units. The antenna units are disposed on the circuit board proximate to a peripheral edge thereof, are arranged in a loop formation, and are divided into a plurality of groups of the antenna units . Each of the multiplexer units is connected electrically to a respective one of the groups of the antenna units for selecting one of the corresponding antenna units and for connecting electrically the selected one of the corresponding antenna units to the RF circuit, thereby achieving the MIMO technique with the independently and simultaneously operating antenna units.

Claims

1. A multiple-input multiple-output (MIMO) antenna device adapted for connecting electrically to a radio frequency (RF) circuit so as to transmit and receive RF signals, said MIMO antenna device comprising:

a circuit board having a peripheral edge;

a number (N) of antenna units disposed on said circuit board proximate to said peripheral edge of said circuit board and arranged in a loop formation, wherein (N) is an integer not smaller than 6 and is a multiple of 3; and

three (1×

(N/3))-multiplexer units disposed on said circuit board, each of said (1×

(N/3))-multiplexer units having (N/3) input terminals that are connected electrically and respectively to (N/3) corresponding ones of said (N) antenna units and being operable to select one of said (N/3) corresponding ones of said antenna units for connecting electrically the selected one of said (N/3) corresponding ones of said antenna units to the RF circuit.

2. The MIMO antenna device as claimed in claim 1, wherein said circuit board has a ground plane, and said (N) antenna units are disposed to surround said ground plane.

3. The MIMO antenna device as claimed in claim 1, further comprising a controller connected electrically to said (1×

(N/3))-multiplexer units, each of said (1×

(N/3))-multiplexer units being controlled by said controller to select one of said antenna units connected thereto for connecting electrically the selected one of said antenna units to the RF circuit.

4. The MIMO antenna device as claimed in claim 3, further comprising a signal-source determining unit that is connected electrically to said controller and that is adapted to be coupled to the RF circuit, said signal-source determining unit being operable to determine a source of a RF signal based on intensity of the RF signal received by each of said (N) antenna units, and to generate a control signal corresponding to the source of the RF signal for controlling said controller, said controller being responsive to the control signal so as to control each of said (1×

(N/3))-multiplexer units to select one of said (N/3) corresponding ones of said (N) antenna units able to receive a maximum intensity of the RF signal relative to other ones of said antenna units in said (N/3) corresponding ones of said (N) antenna units for connecting electrically the selected one of said antenna units to the RF circuit.

5. The MIMO antenna device as claimed in claim 2, wherein each of said (N) antenna units is a one-wavelength loop antenna and includes a dielectric substrate that has a surface, and a first loop antenna and a second loop antenna that are disposed on said surface of said dielectric substrate, said first and second loop antennas being operable in first and second frequency bands, respectively.

6. The MIMO antenna device as claimed in claim 5, wherein said first loop antenna has a first feed portion and a first ground portion, said first feed portion being substantially parallel to said first ground portion, said first feed portion being adapted to be coupled to the RF circuit so as to permit feeding of the RF signal therebetween, said first ground portion being connected electrically to said ground plane of said circuit board.

7. The MIMO antenna device as claimed in claim 5, wherein said second loop antenna has a second feed portion adapted to be coupled to the RF circuit so as to permit feeding of the RF signal therebetween, and a second ground portion connected electrically to said ground plane of said circuit board, said second feed portion being substantially parallel to said second ground portion.

8. The MIMO antenna device as claimed in claim 1, wherein (N) is equal to 18, each of said (1×

(N/3))-multiplexer units being a (1×

6)-multiplexer unit connected electrically to six corresponding ones of said antenna units,

each of said (1×

6)-multiplexer units including a (1×

2)-multiplexer and two (1×

3)-multiplexers connected to said (1×

2)-multiplexer,

each of said (1×

3)-multiplexers being connected electrically to three corresponding ones of said antenna units and being operable to select one of said three corresponding ones of said antenna units for connecting electrically the selected one of said three corresponding ones of said antenna units to said (1×

2)-multiplexer,

said (1×

2)-multiplexer being operable to select one of said antenna units connected electrically thereto via said (1×

3)-multiplexers for connecting electrically said antenna unit selected thereby to the RF circuit.

9. The MIMO antenna device as claimed in claim 1, wherein (N) is equal to 18, each of said ((1×

(N/3))-multiplexer units being a (1×

6)-multiplexer unit connected electrically to six corresponding ones of said antenna units,

each of said (1×

6)-multiplexer units including a (1×

3)-multiplexer and three (1×

2)-multiplexers connected to said (1×

3)-multiplexer,

each of said (1×

2)-multiplexers being connected electrically to two corresponding ones of said antenna units and being operable to select one of said two corresponding ones of said antenna units for connecting electrically the selected one of said two corresponding ones of said antenna units to said (1×

3)-multiplexer, said (1×

3)-multiplexer being operable to select one of said antenna units connected electrically thereto via said (1×

2)-multiplexers for connecting electrically said antenna unit selected thereby to the RF circuit.

10. The MIMO antenna device as claimed in claim 1, wherein (N) is equal to 6, each of said ((1×

(N/3))-multiplexer units being a (1×

2)-multiplexer connected electrically to two corresponding ones of said antenna units, each of said (1×

2)-multiplexers being operable to select one of said two corresponding ones of said antenna units for connecting electrically the selected one of said two corresponding ones of said antenna units to the RF circuit.