Wireless Communication Mimo System With Repeaters

• US 20080293358A1
• Filed: 12/08/2005
• Published: 11/27/2008
• Est. Priority Date: 12/08/2005
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Goransson, Bo, Andersson, Mats H
• Granted Patent: US 8,032,080 B2
• Time in Patent Office: Days
• US Class Current: 455/8
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04B 7/026 Co-operative diversity, e.g. using fixed or mobile stations as relays
• CPC Class Codes: H04B 7/1555 Selecting relay station antenna mode, e.g. selecting omnidirectional -, directional beams, selecting polarizations
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels

Abstract

The present invention relates to a wireless communication system (C) comprising at least one base station (1) in a communication cell (2), from which base station (1) at least two essentially uncorrelated antenna radiation lobes (7, 8, 9, 10) are formed. Each antenna radiation lobe (7, 8, 9, 10) communicates a MIMO (Multiple Input Multiple Output) communication stream. The system (C) further comprises at least one repeating transmitter/receiver (repeater) (18, 19, 20, 21), which is arranged for communicating one of the MIMO communication streams to and/or from at least one UE (user equipment) (12). The present invention also relates to a repeater that is a part of the system (C), and a method for communicating at least two MIMO communication streams to and/or from at least one UE (user equipment) (12), using at least one repeater (18, 19, 20, 21).

Claims

1. A wireless communication system (C) comprising at least one base station (1) in a communication cell (2), from which base station (1) at least two essentially uncorrelated antenna radiation lobes (7, 8, 9, 10) are formed, each antenna radiation lobe (7, 8, 9, 10) communicating a MIMO (Multiple Input Multiple Output) communication stream, characterized in that the system (C) further comprises at least one repeating transmitter/receiver (repeater) (18, 19, 20, 21), the at least one repeater (18, 19, 20, 21) being arranged for communicating one of the MIMO communication streams to and/or from at least one UE (user equipment) (12), the UE (12) being equipped with at least two essentially uncorrelated antenna functions.

2. A wireless communication system (C) according to claim 1, characterized in that the communication system (C) is arranged with one frequency band for uplink and another frequency band for downlink.

3. A wireless communication system (C) according to any one of the claims 1 or 2, characterized in that the at least one repeater (18, 19, 20, 21) is placed in such a way that it has a free line of sight to the base station (1).

4. A wireless communication system (C) according to any one of the previous claims, characterized in that each MIMO communication stream is communicated by means of a certain corresponding repeater (18, 19, 20, 21), each repeater (18, 19, 20, 21) being associated with one of the MIMO communication streams.

5. A wireless communication system (C) according to any one of the previous claims, characterized in that each repeater (18, 19, 20, 21) is arranged with a first repeater antenna (22), which has a first radiation lobe (23), and a second repeater antenna (24, 24′

).

6. A wireless communication system (C) according to claim 5, characterized in that the second repeater antenna (24) of at least one repeater (18, 19, 20, 21) is arranged to produce a relatively wide radiation lobe (25, 26, 27, 28).

7. A wireless communication system (C) according to claim 5, characterized in that the second repeater antenna (24) of at least one repeater (18, 19, 20, 21) comprises at least two separate spatially separated antenna elements, enabling space and pattern diversity.

8. A wireless communication system (C) according to claim 5, characterized in that the antenna radiation lobe (25, 26, 27, 28) of the second antenna (24) of at least one repeater (18, 19, 20, 21) is electrically controllable, and where that antenna radiation lobe (25, 26, 27, 28) is relatively narrow and controlled in such a way that the best possible transmission with to the UE is achieved, the information streams still being essentially uncorrelated.

9. A wireless communication system (C) according to claim 8, characterized in that at least one repeater (18, 19, 20, 21) is arranged with a multilobe second antenna (24′

) producing at least two antenna radiation lobes (30, 31, 32, 33) pointing in different directions in azimuth, elevation or both.

10. A wireless communication system (C) according to claim 9, characterized in that the antenna radiation lobes (30, 31, 32, 33) of the multilobe second antenna (24′

) are electrically controllable.

11. A wireless communication system (C) according to any one of the claims 5-10, characterized in that the first antenna radiation lobe (23) is relatively narrow and is fixedly aimed at the base station, being arranged for communication via one of the base station antenna radiation lobes (7, 8, 9, 10).

12. A wireless communication system (C) according to any one of the claims 5-10, characterized in that at least one repeater'"'"'s (18, 19, 20, 21) first antenna (22) has an electrically controllable radiation lobe (23).

13. A wireless communication system (C) according to any one of the previous claims, characterized in that at least one repeater (18, 19, 20, 21) is arranged for creating diversity of any of the types:

time, frequency or phase diversity.

14. A wireless communication system (C) according to any one of the previous claims, characterized in that the base station antenna radiation lobes (7, 8, 9, 10) are electrically controllable.

15. A wireless communication system (C) according to any one of the previous claims, characterized in that the base station (1) antennas (3, 4, 5, 6) are dual polarized, each base station antenna (3, 4, 5, 6) being arranged for communication via two essentially orthogonal polarizations.

16. A wireless communication system (C) according to any one of the previous claims, characterized in that lobe-forming is achieved by means of Butler matrixes (11, 34) or digital beam-forming or both.

17. A repeating transmitter/receiver (repeater) (18, 19, 20, 21), characterized in that the repeater (18, 19, 20, 21) is a part of a wireless communication system (C) according to any one of the claims 1-16.

18. A method for communicating at least two MIMO (Multiple Input Multiple Output) communication streams to and/or from at least one UE (user equipment) (12), comprising the step:

communicating the MIMO communication streams by means of at least two at least two essentially uncorrelated antenna radiation lobes (7, 8, 9, 10);

characterized in that the method further comprises the step;

using at least one repeating transmitter/receiver (repeater) (18, 19, 20, 21) for communicating at least one of the MIMO communication streams to the UE (12).

19. A method according to claim 18, characterized in that the method further comprises the step:

communicating each MIMO communication stream by means of a certain corresponding repeater (18, 19, 20, 21), each repeater (18, 19, 20, 21) being associated with one of the MIMO communication streams.

20. A method according to any one of the claims 18-19, characterized in that at least one repeater (18, 19, 20, 21) uses diversity of any of the types:

time, frequency or phase diversity.