MASTER REFERENCE FOR BASE STATION NETWORK INTERFACE SOURCED FROM DISTRIBUTED ANTENNA SYSTEM

• US 20140243033A1
• Filed: 02/21/2014
• Published: 08/28/2014
• Est. Priority Date: 02/22/2013
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Wala, Philip M., Zavadsky, Dean, Forland, Jody, Cannon, Jeffrey J., Hedin, John M.
• Granted Patent: US 10,020,850 B2
• Time in Patent Office: Days
• US Class Current: 455/517
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H03J 7/04 where the frequency control is accomplished by varying the electrical characteristics of a non-mechanically adjustable element or where the nature of the frequency controlling element is not significant
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04B 7/26 at least one of which is mobile
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A distributed antenna system (DAS) includes: first base station network interface unit that receives first downlink signals from first external device and converts them into first downlink data stream; second base station network interface unit that receives second downlink signals from second external device and them into second downlink data stream; first remote antenna unit communicatively coupled to first base station network interface unit that receives at least one of first downlink data stream and first downlink signal derived from first downlink data stream. First remote antenna unit has first radio frequency converter configured to convert at least one of first downlink data stream and first downlink signal derived from first downlink data stream into first radio frequency band signal and first radio frequency antenna that transmits first radio frequency band signal to first subscriber unit. DAS is configured to transmit a master reference clock to the first external device.

Claims

1. A distributed antenna system comprising:

a first base station network interface unit configured to receive first downlink signals from a first external device external to the distributed antenna system and to convert the first downlink signals into a first downlink data stream;

a second base station network interface unit configured to receive second downlink signals from a second external device external to the distributed antenna system and to convert the second downlink signals into a second downlink data stream;

a first remote antenna unit communicatively coupled to the first base station network interface unit and configured to receive at least one of the first downlink data stream from the first base station network interface unit and a first downlink signal derived from the first downlink data stream;

the first remote antenna unit having a first radio frequency converter configured to convert at least one of the first downlink data stream and the first downlink signal derived from the first downlink data stream into a first radio frequency band signal and a first radio frequency antenna configured to transmit the first radio frequency band signal to a first subscriber unit; and

wherein the distributed antenna system is configured to transmit a master reference clock to the first external device.

2. The distributed antenna system of claim 1, wherein the distributed antenna system is configured to generate the master reference clock internally.

3. The distributed antenna system of claim 1, wherein the distributed antenna system is configured to derive the master reference clock from the second external device.

4. The distributed antenna system of claim 3, wherein the distributed antenna system is configured to derive the master reference clock from the second external device by being configured to lock the master reference clock to a clock embedded in the second downlink signals received from the second external device.

5. The distributed antenna system of claim 1, wherein the distributed antenna system is configured to transmit the master reference clock to the first external device by being configured to transmit first uplink signals to the first external device through the first base station network interface unit, wherein the first uplink signals are clocked using the master reference clock such that the master reference clock is embedded in the uplink signals.

6. The distributed antenna system of claim 4, wherein the first external device is configured to lock its clock to the master reference clock embedded in the first uplink signals.

7. The distributed antenna system of claim 1, wherein the distributed antenna system is configured to transmit the master reference clock to the first external device by being configured to transmit the master reference clock across a separate master reference clock channel.

8. The distributed antenna system of claim 1, further comprising:

a hybrid expansion unit communicatively coupled between the first base station network interface unit and the first remote antenna unit and configured to receive the first downlink data stream and convert the first downlink data stream to the first downlink signal derived from the first downlink data stream;

wherein the first remote antenna unit is further configured to receive the first downlink signal derived from the first downlink data stream and to convert the first downlink signal derived from the first downlink data stream into the second radio frequency band signal.

9. The distributed antenna system of claim 8, wherein the first downlink signal derived from the first downlink data stream is a downlink analog intermediate frequency signal.

10. The distributed antenna system of claim 1, wherein the first remote antenna unit is further communicatively coupled to the second base station network interface unit and configured to receive at least one of the second downlink data stream from the second base station network interface unit and a second downlink signal derived from the second downlink data stream;

the first remote antenna unit further having a second radio frequency converter configured to convert at least one of the second downlink data stream and the second downlink signal derived from the second downlink data stream into a second radio frequency band signal and a second radio frequency antenna configured to transmit the second radio frequency band signal to a second subscriber unit.

11. The distributed antenna system of claim 1, wherein the first remote antenna unit is further communicatively coupled to the second base station network interface unit and configured to receive at least one of the second downlink data stream from the second base station network interface unit and a second downlink signal derived from the second downlink data stream;

the first remote antenna unit further having a second radio frequency converter configured to convert at least one of the second downlink data stream and the second downlink signal derived from the second downlink data stream into a second radio frequency band signal; and

wherein the first radio frequency antenna is further configured to transmit the second radio frequency band signal to a second subscriber unit.

12. The distributed antenna system of claim 1, further comprising a second remote antenna unit communicatively coupled to the second base station network interface unit and configured to receive at least one of the second downlink data stream from the second base station network interface unit and a second downlink signal derived from the second downlink data stream;

and

the second remote antenna unit further having a second radio frequency converter configured to convert at least one of the second downlink data stream and the second downlink signal derived from the second downlink data stream into a second radio frequency band signal and a second radio frequency antenna configured to transmit the second radio frequency band signal to a second subscriber unit.

13. The distributed antenna system of claim 1, further comprising:

a distributed antenna switch communicatively coupled between both the first base station network interface unit and the second base station network interface unit and the first remote antenna unit, the distributed antenna switch configured to receive the first downlink data stream from the first base station network interface unit and the second downlink data stream from the second base station network interface unit and to aggregate the first downlink data stream with the second downlink data stream into an aggregate downlink data stream;

the distributed antenna switch further configured to transmit the aggregate downlink data stream to the first remote antenna unit; and

the first remote antenna unit further configured to receive the aggregate downlink data stream and to extract the first downlink data stream from the aggregate downlink data stream.

14. The distributed antenna system of claim 13, further comprising a second remote antenna unit communicatively coupled to the second base station network interface unit through the distributed antenna switch and configured to receive aggregate downlink data stream and to extract the second downlink data stream from the second aggregate downlink data stream;

the second remote antenna unit further having a second radio frequency converter configured to convert the second downlink data stream into a second radio frequency band signal and a second radio frequency antenna configured to transmit the second radio frequency band signal to a second subscriber unit.

15. The distributed antenna system of claim 1, wherein the first radio frequency antenna is further configured to receive a first uplink radio frequency band signal from the first subscriber unit;

wherein the first radio frequency converter is further configured to convert the first uplink radio frequency band signal to a first uplink data stream;

wherein the first remote antenna unit is further configured to communicate the first uplink data stream to the first base station network interface unit;

wherein the first base station network interface unit is configured to receive the first uplink data stream from the first remote antenna unit;

wherein the first network interface is configured to convert the first uplink data stream into first uplink signals; and

wherein the first base station network interface unit is configured to communicate the first uplink signals to the first external device.

16. The distributed antenna system of claim 1, wherein the first radio frequency antenna is further configured to receive a first uplink radio frequency band signal from the first subscriber unit;

wherein the first radio frequency converter is further configured to convert the first uplink radio frequency band signal to a first uplink analog intermediate frequency signal;

wherein the first remote antenna unit is further configured to communicate the first uplink analog intermediate frequency signals to a hybrid expansion unit;

wherein the hybrid expansion unit is configured to receive the first uplink analog intermediate frequency signals from the first remote antenna unit;

wherein the hybrid expansion unit is configured to convert the first uplink analog intermediate frequency signals to a first uplink data stream;

wherein the hybrid expansion unit is configured to communicate the first uplink data stream to the first base station network interface unit;

wherein the first base station network interface unit is configured to receive the first uplink data stream from the hybrid expansion unit;

wherein the first network interface is configured to convert the first uplink data stream into first uplink signals; and

wherein the first base station network interface unit is configured to communicate the first uplink signals to the first external device.

17. The distributed antenna system of claim 1, wherein the first external device is a base band unit of a wireless access base station.

18. The distributed antenna system of claim 1, wherein the first external device is a Common Public Radio Interface (CPRI) base station, wherein the first base station network interface unit is a CPRI converter interface communicatively coupled to a CPRI base station, the CPRI converter interface configured to receive CPRI data from the CPRI base station, the CPRI converter interface further configured to convert the CPRI data into a first downlink data stream of the plurality of downlink data streams.

19. The distributed antenna system of claim 1, wherein the first downlink data stream is a baseband data stream.

20. The distributed antenna system of claim 19, wherein the baseband data stream includes quadrature samples of I/Q pairs.

21. A method comprising:

receiving a first downlink signal from a first external device external to a distributed antenna system via a first base station network interface unit;

converting the first downlink signal into a first downlink data stream at the first base station network interface unit;

receiving a second downlink signal from a second external device external to the distributed antenna system via a second base station network interface unit;

converting the second downlink signal into a second downlink data stream at the second base station network interface unit;

communicating the first downlink data stream from the first base station network interface unit to at least one of a first remote antenna unit and an intermediary device;

converting at least one of the first downlink data stream and a first downlink signal derived from the first downlink data stream at the intermediary device into a first radio frequency band signal at the first remote antenna unit;

transmitting the first radio frequency band signal to a first subscriber unit at the first remote antenna unit;

transmitting a master reference clock to the first external device through the first base station network interface unit.

22. The method of claim 21, further comprising:

generating the master reference clock within the distributed antenna system.

23. The method of claim 21, further comprising:

deriving the master reference clock from the second external device through the second base station network interface unit.

24. The method of claim 23, wherein deriving the master reference clock from the second external device through the second base station network interface unit includes:

locking the master reference clock to a clock embedded in the second downlink signals received from the second external device.

25. The method of claim 21, wherein transmitting the master reference clock to the first external device includes transmitting uplink signals to the first external device through the first base station network interface unit, wherein the uplink signals are clocked using the master reference clock such that the master reference clock is embedded in the uplink signals.

26. The method of claim 25, further comprising:

locking a reference clock of the first device of the devices external to the distributed antenna system to the master reference clock embedded in the uplink signals.

27. The method of claim 21, wherein transmitting the master reference clock to the first device of the devices external to the distributed antenna system includes transmitting the master reference clock across a separate master reference clock channel.

28. The method of claim 21, further comprising:

communicating the first downlink data stream to a hybrid expansion unit communicatively coupled between the first base station network interface unit and the first remote antenna unit;

converting the first downlink data stream to the first downlink signal derived from the first downlink data stream at the hybrid expansion unit;

communicating the first downlink signal derived from the first downlink data stream from the hybrid expansion unit to the first remote antenna unit; and

converting the first downlink signal derived from the first downlink data stream into a first radio frequency band signal at the first remote antenna unit.

29. The method of claim 28, wherein the first downlink signal derived from the first downlink data stream is a downlink analog intermediate frequency signal.

30. The method of claim 21, further comprising:

communicating the second downlink data stream from the second base station network interface unit to the first remote antenna unit;

converting the second downlink data stream into a second radio frequency band signal at the first remote antenna unit; and

transmitting the second radio frequency band signal to a second subscriber unit at the first remote antenna unit.

31. The method of claim 21, further comprising:

communicating the second downlink data stream from the second base station network interface unit to a hybrid expansion unit communicatively coupled between the second base station network interface unit and the first remote antenna unit;

converting the second downlink data stream to a second downlink signal derived from the first downlink data stream at the hybrid expansion unit;

communicating the second downlink signal derived from the second downlink data stream from the hybrid expansion unit to the first remote antenna unit;

converting the second downlink signal derived from the second downlink data stream into a second radio frequency band signal at the first remote antenna unit; and

transmitting the second radio frequency band signal to a second subscriber unit at the first remote antenna unit.

32. The method of claim 21, further comprising:

communicating the second downlink data stream from the second base station network interface unit to a second remote antenna unit;

converting the first downlink data stream into a second radio frequency band signal at the second remote antenna unit; and

transmitting the second radio frequency band signal to a second subscriber unit at the second remote antenna unit.

33. The method of claim 21, further comprising:

communicating the second downlink data stream from the second base station network interface unit to a hybrid expansion unit communicatively coupled between the second base station network interface unit and the first remote antenna unit;

converting the second downlink data stream to a second downlink signal derived from the first downlink data stream at the hybrid expansion unit;

communicating the second downlink signal derived from the second downlink data stream from the hybrid expansion unit to the first remote antenna unit; and

converting the second downlink signal derived from the second downlink data stream into a second radio frequency band signal at the second remote antenna unit; and

transmitting the second radio frequency band signal to a second subscriber unit at the second remote antenna unit.

34. The method of claim 21, further comprising:

communicating the first downlink data stream from the first base station network interface unit to a distributed antenna switch communicatively coupled between the first base station network interface unit and the first distributed antenna switch;

communicating the second downlink data stream from the second base station network interface unit to the distributed antenna switch communicatively coupled between the second base station network interface unit and the second distributed antenna switch;

aggregating the first downlink data stream with the second downlink data stream into an aggregate downlink data stream at the distributed antenna switch;

communicating the aggregate downlink data stream to the first remote antenna unit; and

extracting the first downlink data stream from the aggregate downlink data stream at the first remote antenna unit.

35. The method of claim 21, further comprising:

receiving a first uplink radio frequency band signal from the first subscriber unit at the first remote antenna unit;

converting the first uplink radio frequency band signal to a first uplink data stream at the first remote antenna unit;

communicating the first uplink data stream from the first remote antenna unit to the first base station network interface unit;

converting the first uplink data stream into first uplink signals at the first base station network interface; and

communicating the first uplink signals to the first external device at the first base station network interface.

36. The method of claim 21, further comprising:

receiving a first uplink radio frequency band signal from the first subscriber unit at the first remote antenna unit;

converting the first uplink radio frequency band signal to a first uplink analog intermediate frequency signal at the first remote antenna unit;

communicating the first analog intermediate frequency signal from the first remote antenna unit to a hybrid expansion unit communicatively coupled between the first base station network interface and the first remote antenna unit;

converting the first uplink analog intermediate frequency signal to a first uplink data stream at the hybrid expansion unit;

communicating the first uplink data stream from the hybrid expansion unit to the first base station network interface unit;

converting the first uplink data stream into first uplink signals at the first base station network interface; and

communicating the first uplink signals to the first external device at the first base station network interface.

37. The method of claim 21, wherein the first downlink data stream is a baseband data stream.

38. The method of claim 37, wherein the baseband data stream includes quadrature samples of I/Q pairs.

39. A base station comprising:

a base station network interface configured to be communicatively coupled to a corresponding base station network interface of a distributed antenna system and configured to communicate signals with the distributed antenna system;

a clocking unit configured to receive a master clock signal from the distributed antenna system; and

wherein the base station is further configured to synchronize itself with the distributed antenna system using the master clock signal from the distributed antenna system.

40. The base station of claim 39, wherein the clocking unit is configured to receive the master clock signal from the distributed antenna system by being configured to lock to the master clock embedded in an uplink signal received from the distributed antenna system.

41. The base station of claim 39, wherein the clocking unit is configured to receive the master clock signal from the first external device across a separate master reference clock channel.

42. The base station of claim 39, wherein the master reference clock is generated within the distributed antenna system.

43. The base station of claim 39, wherein the master reference clock is derived from an device external to the distributed antenna system.