Method and system for extending MIMO wireless service

• US 8,391,875 B1
• Filed: 02/22/2008
• Issued: 03/05/2013
• Est. Priority Date: 02/22/2008
• Status: Active Grant

• Current Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Satapathy, Durga, Rausch, Walter, Kelly, Ivy
• Primary Examiner(s): Brandt, Christopher M
• Application Number:
  US12/035,783
• Time in Patent Office: 1,838 Days
• Field of Search: 455/555, 455/446, 455/448, 455/561, 455/562.1, 455/443, 455/444, 455/445, 455/449, 370/315
• US Class Current: 455/446
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04L 1/0618 Space-time coding
• CPC Class Codes: H04L 2001/0097 Relays
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

Disclosed herein is a method and system for extending MIMO service in a wireless communications system. The system comprises a base station, a remote system, and a host system communicatively coupled to the base station and the remote system. The base station is configured to generate, from a baseband signal, a downlink signal comprising a plurality of downlink signal streams, including at least a first downlink signal stream and a second downlink signal stream. Accordingly, the base station may include a first and a second antenna that are configured to transmit the first and second downlink signal streams, respectively. The remote system provides wireless service in a remote coverage area. Further, the remote system is configured to transmit a downlink signal as a plurality of downlink signal streams. The host system is communicatively coupled to the base station and to the remote system and configured to relay the downlink signal streams from the base station to the remote system.

Claims

1. A system comprising:

a base station providing wireless service in a base coverage area, said base station configured to generate from a baseband signal, a downlink signal comprising a plurality of downlink signal streams, including at least a first downlink signal stream and a second downlink signal stream;

a remote system configured to extend the wireless service of the base station to a remote coverage area, said remote system configured to wirelessly transmit said downlink signal streams, said remote system having a plurality of antennas, including at least a first remote antenna and a second remote antenna; and

a host system communicatively coupled to said base station and to said remote system, wherein said host system substantially controls said remote system, said host system being configured to;

receive said first downlink signal stream from said base station and convey said first downlink signal stream to said remote system for transmission through said first remote antenna; and

receive said second downlink signal stream from said base station and convey said second downlink signal stream to said remote system for transmission through said second remote antenna.

2. The system of claim 1, wherein said base station comprises a plurality of antennas, including at least a first base station antenna and a second base station antenna, the base station being configured to generate said first downlink signal stream and said second downlink signal stream from a baseband signal and to transmit said first downlink signal stream through said first base station antenna and said second downlink signal stream through said second base station antenna.

3. The system of claim 2, wherein said first and second base station antennas are configured to support spatial multiplexing.

4. The system of claim 1, wherein said first and second downlink signal streams are space-time coded.

5. The system of claim 1, wherein said first and second remote antennas are configured to support spatial multiplexing.

6. The system of claim 1, wherein said first and second remote antennas are configured to support space-time coding.

7. The system of claim 1, further comprising:

at least one fiber-optic link carrying said first and second downlink signal streams between said host system and said remote system.

8. The system of claim 1, further comprising:

at least one fiber-optic link carrying said first and second downlink signal streams between said base station and said host system.

9. The system of claim 1, further comprising:

at least one additional remote system configured to extend the wireless service of the base station to at least one additional remote coverage area, said additional remote system being configured to wirelessly transmit said downlink signal streams, said remote system having a plurality antennas, including at least a first additional remote antenna and a second additional remote antenna; and

at least one additional host system communicatively coupled to said base station and to said additional remote system, said additional host system being configured to;

receive said first downlink signal stream from said base station and convey said first downlink signal stream to said additional remote system for transmission through said first additional remote antenna; and

receive said second downlink signal stream from said base station and convey said second downlink signal stream to said additional remote system for transmission through said second additional remote antenna.

10. The system of claim 1, wherein said remote system is further configured to:

receive a plurality of uplink signal streams through said first and second remote antennas, wherein a wireless communication device operating in said remote coverage area transmits an uplink signal as said uplink signal streams; and

convey said uplink signal streams to said host system.

11. The system of claim 10, wherein said host system is configured to convey said uplink signal streams to said base station.

12. The system of claim 11, wherein said base station is configured to transmit said downlink signal streams and to receive said uplink signal streams using time division duplexing.

13. The system of claim 10, wherein said host system is configured to transmit said downlink signal streams and to receive said uplink signal streams using frequency division duplexing.

14. The system of claim 10, wherein said uplink signal streams are received by said remote system as one or more combinations of said plurality of uplink signal streams.

15. The system of claim 14, wherein said base station is further configured to:

use said one or more combinations of said uplink signal streams as a basis for isolating said uplink signal streams; and

construct said uplink signal from said uplink signal streams.

16. A method for extending multiple-input multiple-output (MIMO) communication service from a base station having a base coverage area, to a remote coverage area, wherein said remote coverage area is at least partially different from said base coverage area, said method comprising:

at said base station, generating a downlink signal comprising two or more signal streams comprising at least a first and a second signal stream;

a host system conveying said signal streams from said base station to a remote system via by receiving said signal streams from said base station and conveying said signal streams from said host system to said remote system, wherein said remote system extends the MIMO communication service of said base station to at least a portion of said remote coverage area, and wherein said host system substantially controls said remote system; and

said remote system wirelessly transmitting said signal streams via a plurality of antennas including at least a first remote antenna and a second remote antenna, wherein the first signal stream is transmitted via said first remote antenna and the second signal stream is transmitted via said second remote antenna.

17. The method of claim 16, wherein said signal streams comprise at least a first radio frequency (RF) signal stream containing a first portion of said downlink signal and a second RF signal stream containing a second portion of said downlink signal.

18. The method of claim 16, wherein said signal streams comprise at least a first radio frequency (RF) signal stream containing said downlink signal and a second RF signal stream containing said downlink signal.

19. The method of claim 18, wherein conveying said signal streams from said base station to a remote system located in said remote coverage area comprises:

conveying said signal streams via at least one fiber-optic link.

20. The method of claim 18, wherein said remote system wirelessly transmitting said signal streams comprises:

transmitting said first RF signal stream through said first remote antenna; and

transmitting said second RF signal stream through said second remote antenna.

21. The method of claim 20, further comprising:

said first remote antenna receiving a first uplink signal stream containing an uplink signal from a mobile station operating in said remote coverage area; and

said second remote antenna receiving a second uplink signal stream containing said uplink signal.

22. The method of claim 21, further comprising:

conveying said first uplink signal stream from said remote system to said base station;

conveying said second uplink signal stream from said remote system to said base station; and

said base station combining said first and second uplink signal streams to generate a combined uplink signal.