ARCHITECTURE TO SUPPORT NETWORK-WIDE MULTIPLE-IN-MULTIPLE-OUT WIRELESS COMMUNICATION

• US 20090022089A1
• Filed: 07/16/2007
• Published: 01/22/2009
• Est. Priority Date: 07/16/2007
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Rudrapatna, Ashok N.
• Granted Patent: US 8,032,183 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04B 7/0671 using different delays between antennas

Abstract

The present invention provides a method of coordinating transmission by and reception by a plurality of antennas associated with a plurality of radio heads. The method includes determining, at a controller, at least one relative time delay associated with a plurality of backhaul links between the controller and the plurality of radio heads. The method also includes providing information indicative of a first signal over the plurality of backhaul links. The method further includes providing timing information over the plurality of backhaul links. The timing information is determined based on the relative time delay(s) such that the plurality of radio heads can use the provided timing information to coherently transmit the first signal using the plurality of antennas and a plurality of controllers to receive mobile unit transmitted information.

Claims

1. A method of coordinating transmission by a plurality of antennas associated with a plurality of radio heads, comprising:

determining, at a controller, at least one relative time delay associated with a plurality of backhaul links between the controller and the plurality of radio heads;

providing, over the plurality of backhaul links, information indicative of a first signal; and

providing timing information over the plurality of backhaul links, the timing information being determined based on said at least one relative time delay such that the plurality of radio heads can use the provided timing information to coherently transmit the first signal using the plurality of antennas.

2. The method of claim 1, wherein determining said at least one relative time delay comprises determining said at least one relative time delay using timing information transmitted over the plurality of backhaul links.

3. The method of claim 1, wherein determining said at least one relative time delay comprises:

providing a plurality of first timing signals over the plurality of backhaul links; and

determining said at least one relative time delay based on a plurality of second timing signals received over the plurality of backhaul links in response to the plurality of first timing signals.

4. The method of claim 1, wherein providing the information indicative of the first signal comprises providing at least one of an analog baseband signal and an oversampled digital baseband signal.

5. The method of claim 1, wherein providing the timing information comprises providing information indicative of a global or universal reference time.

6. The method of claim 1, comprising providing gain or phase information associated with the first signal, the gain or phase information indicating relative gains or phases to be used by the plurality of antennas when transmitting the first signals.

7. A method of coordinated transmission by a plurality of antennas associated with a plurality of radio heads, comprising:

receiving, at one of the plurality of radio heads over at least one of a plurality of backhaul links between at least one controller and the plurality of radio heads, information indicative of a first signal;

receiving, at said one of the plurality of radio heads over said at least one of the plurality of backhaul links, timing information determined based on at least one relative time delay associated with the plurality of backhaul links; and

transmitting, from said at least one antenna and at a time indicated by the provided timing information, the first signal, the first signal being transmitted coherently with transmissions of the first signal by at least one other radio head.

8. The method of claim 7, comprising transmitting timing information over at least one of the plurality of backhaul links, the transmitted timing information being used to determine said at least one relative time delay.

9. The method of claim 7, comprising:

receiving at least one first timing signal over at least one of the plurality of backhaul links; and

providing at least one second timing signal over said at least one of the plurality of backhaul links in response to receiving said at least one first timing signal.

10. The method of claim 7, wherein receiving the information indicative of the first signal comprises receiving at least one of an analog baseband signal and an oversampled digital baseband signal.

11. The method of claim 7, wherein receiving the timing information comprises receiving information indicative of a global or universal reference time.

12. The method of claim 7, comprising receiving phase information associated with the first signal, and wherein transmitting the first signal comprises transmitting the first signal based on the received phase information.

13. A method of combining information received by a plurality of antennas associated with a plurality of radio heads, comprising:

receiving, over a plurality of backhaul links between a controller and the plurality of radio heads, information indicative of at least one first signal transmitted by at least one mobile unit and received by the plurality of antennas; and

combining, coherently, said information received over the plurality of backhaul links using timing information associated with the plurality of backhaul links.

14. The method of claim 13, comprising:

receiving timing information from the plurality of radio heads over the plurality of backhaul links; and

combining, coherently, said information using the timing information received from the plurality of radio heads.

15. The method of claim 13, comprising:

providing a plurality of first timing signals over the plurality of backhaul links; and

combining, coherently, said information based on a plurality of second timing signals received over the plurality of backhaul links in response to the plurality of first timing signals.

16. The method of claim 13, wherein receiving the information indicative of the first signal comprises receiving at least one of an analog baseband signal and an oversampled digital baseband signal.

17. A method of combining information received by a plurality of antennas associated with a plurality of radio heads that communicate with at least one controller over a plurality of backhaul links, comprising:

transmitting, over at least one backhaul link between a first radio head and said at least one controller, information indicative of at least one first signal received by at least one antenna associated with the first radio head such that the information transmitted by the first radio head can be coherently combined with information transmitted over at least one backhaul link by at least one second radio head using timing information determined based on a plurality of signals transmitted over the plurality of backhaul links.

18. The method of claim 17, comprising:

providing timing information associated with the transmitted information such that the information transmitted by the first radio head can be coherently combined with information transmitted over at least one backhaul link by at least one second radio head using the provided timing information.

19. The method of claim 17, comprising:

receiving a first timing signal over the backhaul link; and

providing a second timing signal over the backhaul link in response to the first timing signal.

20. The method of claim 17, wherein transmitting the information indicative of the first signal comprises transmitting at least one of an analog baseband signal and an oversampled digital baseband signal.