Code-division, multiple-access base station having transmit diversity

• US 6,539,209 B1
• Filed: 05/30/2000
• Issued: 03/25/2003
• Est. Priority Date: 05/30/2000
• Status: Expired due to Term

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Rubin, Harvey, LaConte, Peter Keith, Dajer, Miguel
• Primary Examiner(s): Congle, Thanh
• Assistant Examiner(s): TRAN, TUAN A
• Application Number:
  US09/580,775
• Time in Patent Office: 1,029 Days
• Field of Search: 455/277.1, 455/277.2, 455/101, 455/73, 455/562, 455/102, 455/103, 375/267, 375/260, 375/299, 375/146, 342/423, 342/463, 342/464
• US Class Current: 455/101
• CPC Class Codes: H04B 7/0491 using two or more sectors, i.e. sector diversity
• CPC Class Codes: H04B 7/0613 using simultaneous transmission H04B7/0686 takes precedence

Abstract

A single base station supports the non-diversity transmission of a first digital signal type and the diversity transmission of a second digital signal type. The base station includes primary channel boards for modulating and encoding a first digital signal type and secondary channel boards for modulating and encoding a second digital signal type. A first group of transmit radio modules accept the first digital signal type and the second digital signal type and provides a composite electromagnetic output signal. Each transmit radio module is associated with a different sector. A second group of transmit radio modules accept the second digital signal type from secondary channel boards and provide a diverse electromagnetic output signal for complementing the composite electromagnetic output signal.

Claims

1. A base station comprising:

a plurality of primary channel boards for modulating and encoding a first digital signal type;

a plurality of secondary channel boards for modulating and encoding a second digital signal type;

a first plurality of transmit radio modules for accepting the first digital signal type and the second digital signal type and providing a composite electromagnetic output signal, each transmit radio module associated with a different sector; and

a second plurality of transmit radio modules for accepting the second digital signal type from secondary channel boards and for providing a diverse electromagnetic output signal for complementing the composite electromagnetic output signal.

2. The base station according to claim 1 further comprising a digital combiner coupled to the primary channel boards and the secondary channel boards, the first plurality of radio modules accepting the second digital signal type from the combiner.

3. The base station according to claim 2 wherein the digital combiner, the secondary channel boards and the second plurality of transmit radio modules represent an upgrade assembly for addition to an existing base station including the primary channel boards and the first plurality of transmit radio modules.

4. The base station according to claim 2 wherein an output interface of a Kth secondary channel board of the secondary channel boards is coupled to the digital combiner.

5. The base station according to claim 1 further comprising:

a first set of antennas for transmitting the composite electromagnetic output signal associated with the first plurality of radio modules; and

a second set of antennas for transmitting the diverse electromagnetic output signal, the second set of antennas being spatially diverse from the first set of antennas and associated with the second plurality of radio modules.

6. The base station according to claim 1 wherein the first set of antennas and the second set of antennas are adapted to cover the same sectors.

7. The base station according to claim 1 wherein the first digital signal type comprises an International Standard (IS)-95A signal and wherein the second digital signal type comprises an IS-95C signal.

8. The base station according to claim 1 wherein the first digital signal type comprises an International Standard (IS)-95B signal and wherein the second digital signal type comprises an IS-95C signal.

9. The base station according to claim 1 wherein a controller is coupled to the primary channel boards and the secondary channel boards.

10. The base station according to claim 1 wherein an output interface of a Kth secondary channel board of the secondary channel boards is coupled to an input interface of a first primary channel board of the primary channel boards, where K is the total number of secondary channel boards.

11. The base station according to claim 1 wherein an output interface of a Kth secondary channel board of the secondary channel boards is coupled to an output channel board associated with the primary channel boards, where K is the total number of secondary channel boards, M−

1 is the total number of primary channel boards, and M equals K.

12. A base station comprising:

primary channel boards coupled in tandem to route at least a first digital signal type to signal branches associated with corresponding different sectors;

a first plurality of transmit radio modules providing a first group of signal branches, each transmit radio module associated with a corresponding one of the different sectors, the first plurality of transmit radio modules accepting at least the first signal type from the primary channel boards;

a second plurality of transmit radio modules providing a second group of signal branches; and

secondary channel boards coupled in tandem, the secondary channel boards adapted to route a second digital signal type between the first signal branches and the second signal branches.

13. The base station according to claim 12 wherein an output stage of the secondary channel boards is coupled to an input stage of the primary channel boards.

14. The base station according to claim 12 wherein the primary channel boards include M boards and the secondary channel boards include K boards with M equaling K;

an output interface of the Kth secondary channel board being coupled to an input interface of the first primary channel board.

15. The base station according to claim 12 further comprising an output channel board associated with M−

1 primary channel boards, the secondary channel boards including K boards with M equaling K;

an output interface of the Kth secondary channel board being coupled to an input interface of the output channel board.

16. The base station according to claim 12 further comprising:

a pair of spatially diverse antennas for each sector, the second digital signal type and the first digital signal type sharing one antenna within the pair, the second digital signal type carried on another antenna within the same pair.

17. The base station according to claim 12 wherein the first digital signal type comprises an (International Standard) IS-95A signal and wherein the second digital signal type comprises an IS-95C signal.

18. The base station according to claim 12 wherein the first digital signal type comprises an (International Standard) IS-95B signal and wherein the second digital signal type comprises an IS-95C signal.

19. The base station according to claim 12 wherein the secondary channel boards and the second plurality of transmit radio modules represent a upgrade assembly for addition to an existing base station including the first transmit modules and the primary channel boards.

20. The base station according to claim 12 wherein a controller is coupled to the primary channel boards and the secondary channel boards.

21. The base station according to claim 12 the primary channel boards and the secondary channel boards are coupled to each other via an optical interface.

22. The base station according to claim 12 wherein primary channel boards and the secondary channel boards are coupled to each other via a multiconductor cable.

23. A method for transmitting transmit diversity signals, the method comprising:

modulating and encoding a first digital signal type;

modulating and encoding a second digital signal type;

combining the first digital signal type and the second digital signal type to provide a composite electromagnetic output signal associated with at least one coverage area; and

providing a diverse electromagnetic output signal, for complementing the composite electromagnetic output signal, based on the second digital signal type.

24. The method according to claim 23 further comprising:

transmitting the composite electromagnetic output signal from at least one of a first set of antennas; and

transmitting the diverse electromagnetic output signal from at least one of a second set of antennas, the second set of antennas being spatially diverse from the first set of antennas.

25. The method according to claim 24 further comprising the step of arranging the first set of antennas and the second set of antennas to cover substantially the same sectors.

26. The method according to claim 23 wherein the first digital signal type comprises an International Standard (IS)-95A signal and wherein the second digital signal type comprises an IS-95C signal.

27. The method according to claim 23 wherein the first digital signal type comprises an International Standard (IS)-95B signal and wherein the second digital signal type comprises an IS-95C signal.

28. The method according to claim 23 further comprising transmitting the composite electromagnetic output signal over at least two carriers within different frequency ranges.

29. The method according to claim 23 further comprising transmitting the diverse electromagnetic output signal over at least two carriers within different frequency ranges.

30. The method according to claim 23 further comprising alternating transmission of the composite electromagnetic output signal between or among different diverse antennas in accordance with a defined sequence.

31. The method according to claim 23 further comprising alternating transmission of the diverse electromagnetic output signal between or among different diverse antennas in accordance with a defined sequence.