Timing adjustments for small cell distributed antenna systems
View Patent ↗A distributed antenna system includes a host unit communicatively coupled to a first service provider interface which receives a first signal from the first service provider interface; and a first remote antenna unit communicatively coupled to the host unit, the first remote antenna unit having a first antenna. A base station to which the distributed antenna system is communicatively coupled is configured with a subscriber access timing window having a minimum allowed delay and a maximum allowed delay. The distributed antenna system is configured so that a first total delay between the host unit and the first remote antenna unit is equal to or greater than the minimum allowed delay. The first antenna of the first remote antenna unit is configured to communicate the first signal to a first subscriber unit.
1. A distributed antenna system comprising:
a host unit communicatively coupled to a first service provider interface which receives a first signal from the first service provider interface;
a first remote antenna unit communicatively coupled to the host unit, the first remote antenna unit having a first antenna;
wherein a base station to which the distributed antenna system is communicatively coupled is configured with a subscriber access timing window having a minimum allowed delay and a maximum allowed delay;
wherein the distributed antenna system is configured so that a first total delay between the host unit and the first remote antenna unit is equal to or greater than the minimum allowed delay; and
wherein the first antenna of the first remote antenna unit is configured to communicate the first signal to a first subscriber unit, wherein a coverage area of communication from the first antenna of the first remote antenna unit is proportional to the first total delay.
2. The distributed antenna system of claim 1 , wherein the first total delay comprises at least one of:
a first inherent delay in the distributed antenna system between the host unit and the first remote antenna unit;
a first propagation delay between the host unit and the first remote antenna unit;
and
a first additional configurable delay.
3. The distributed antenna system of claim 1 , wherein the first total delay comprises a first configurable delay.
4. The distributed antenna system of claim 1 , wherein a coverage area of communication from the first antenna of the first remote antenna unit becomes smaller as the first total delay increases.
5. The distributed antenna system of claim 1 , wherein the first remote antenna unit is communicatively coupled to the host unit via a physical medium.
6. The distributed antenna system of claim 5 , wherein the physical medium is at least one of a fiber optical cable, a coaxial cable, or twisted pair.
7. The distributed antenna system of claim 1 , wherein the first remote antenna unit is communicatively coupled to the host unit via a wireless medium.
8. The distributed antenna system of claim 1 , wherein the first service provider interface is configured to output, and receive as input, respective digital baseband data; and
wherein the first signal is a digital baseband data signal.
9. The distributed antenna system of claim 8 , wherein the digital baseband data comprises in-phase digital baseband data and quadrature digital baseband data; and
wherein the first signal comprises in phase digital baseband data and quadrature digital baseband data.
10. The distributed antenna system of claim 8 , wherein the host unit further comprises a baseband interface that receives from, and outputs to, the first service provider interface respective digital baseband data.
11. The distributed antenna system of claim 10 , wherein the baseband interface is configured to perform a protocol conversion between a first baseband protocol used by the first service provider interface and a second baseband protocol used by the first remote antenna unit.
12. The distributed antenna system of claim 10 , wherein the baseband interface is configured to multiplex digital baseband data.
13. The distributed antenna system of claim 1 , wherein the first service provider interface is configured to output, and receive as input, radio frequency signals; and
wherein the first signal is a radio frequency signal.
14. The distributed antenna system of claim 1 , wherein the service provider interface interacts with a carrier network via an Internet protocol (IP) network.
15. The distributed antenna system of claim 1 , wherein the first remote antenna unit is communicatively coupled to the host unit via at least one intermediary device.
16. The distributed antenna system of claim 15 , wherein the intermediary device comprises an expansion hub.
17. The distributed antenna system of claim 15 , wherein the distributed antenna system is a hybrid distributed antenna system;
wherein the intermediary device comprises a remote server unit that interfaces between a digital portion of the distributed antenna system and an analog portion of the distributed antenna system;
wherein the digital portion of the distributed antenna system includes digital communication between the host unit and the remote server unit;
wherein the remote server unit converts between digital and analog signals; and
wherein the analog portion of the distributed antenna system includes analog communication between the remote server unit and the first remote antenna unit.
18. The distributed antenna system of claim 1 , wherein the distributed antenna system is configured to distribute multiple services.
19. The distributed antenna system of claim 1 , wherein the distributed antenna system is coupled to multiple wireless service providers' networks.
20. The distributed antenna system of claim 1 , wherein the distributed antenna system is configured for use in at least one of: in-building applications, outdoor applications, enterprise applications, public safety applications, and military applications.
21. The distributed antenna system of claim 1 , further comprising groups of the remote antenna units that are configurable for local joint beamforming and/or joint transmission groups of cells.
22. The distributed antenna system of claim 1 , further comprising:
a second remote antenna unit communicatively coupled to the host unit, the second remote antenna unit having a second antenna;
wherein the distributed antenna system is configured so that a second total delay between the host unit and the second remote antenna unit is equal to or greater than the minimum allowed delay; and
wherein the second antenna of the second remote antenna unit is configured to communicate the first signal to a second subscriber unit.
23. The distributed antenna system of claim 22 , wherein the second total delay comprises at least one of:
a second inherent delay in the distributed antenna system between the host unit and the second remote antenna unit;
a second propagation delay between the host unit and the second remote antenna unit; and
a second additional configurable delay.
24. The distributed antenna system of claim 22 , wherein a coverage area of communication from the second antenna of the second remote antenna unit is proportional to the second total delay.
25. The distributed antenna system of claim 22 , wherein the second remote antenna unit is communicatively coupled to the host unit via a physical medium.
26. The distributed antenna system of claim 25 , wherein the physical medium is at least one of a fiber optic cable, a coaxial cable, or twisted pair.
27. The distributed antenna system of claim 1 , further comprising:
wherein the host unit is further communicatively coupled to a second service provider interface which receives a second signal from the second service provider interface; and
wherein at least one antenna of the first remote antenna unit is configured to communicate the second signal to a second subscriber unit.
28. The distributed antenna system of claim 27 , wherein the second service provider interface is configured to output, and receive as input, respective digital baseband data; and
wherein the second signal is a digital baseband data signal.
29. The distributed antenna system of claim 27 , wherein the second service provider interface is configured to output, and receive as input, radio frequency signals; and
wherein the second signal is a radio frequency signal.
30. The distributed antenna system of claim 27 , wherein the second remote antenna unit is communicatively coupled to the host unit via at least one intermediary device.
31. The distributed antenna system of claim 1 , further comprising:
wherein the host unit is further communicatively coupled to a second service provider interface which receives a second signal from the service provider interface;
a second remote antenna unit communicatively coupled to the host unit, the second remote antenna unit having a second antenna;
wherein the distributed antenna system is configured so that a second total delay between the host unit and the second remote antenna unit is equal to or greater than the minimum allowed delay; and
wherein the second antenna of the second remote antenna unit is configured to communicate the second signal to a second subscriber unit.
32. The distributed antenna system of claim 31 , wherein the second total delay comprises at least one of:
a second inherent delay in the distributed antenna system between the host unit and the second remote antenna unit;
a second propagation delay between the host unit and the second remote antenna unit; and
a second additional configurable delay.
33. The distributed antenna system of claim 31 , wherein the second remote antenna unit is communicatively coupled to the host unit via a physical medium.
34. The distributed antenna system of claim 31 , wherein the second service provider interface is configured to output, and receive as input, respective digital baseband data; and
wherein the second signal is a digital baseband data signal.
35. The distributed antenna system of claim 31 wherein the second service provider interface is configured to output, and receive as input, radio frequency signals; and
wherein the second signal is a radio frequency signal.
36. The distributed antenna system of claim 31 , wherein the second remote antenna unit is communicatively coupled to the host unit via at least one intermediary device.
37. The distributed antenna system of claim 36 , wherein the distributed antenna system is a hybrid distributed antenna system;
wherein the intermediary device comprises a remote server unit that interfaces between a digital portion of the distributed antenna system and an analog portion of the distributed antenna system;
wherein the digital portion of the distributed antenna system includes digital communication between the host unit and the second remote server unit;
wherein the remote server unit converts between digital and analog signals; and
wherein the analog portion of the distributed antenna system includes analog communication between the remote server unit and the second remote antenna unit.
38. A method comprising:
configuring a distributed antenna system to have a first additional delay in addition to a first inherent delay of the distributed antenna system between a host unit and a first remote antenna unit;
wherein the distributed antenna system is communicatively coupled to a base station configured with a subscriber access timing window having a minimum allowed delay and a maximum allowed delay;
wherein a first total delay of the first additional delay and the first inherent delay of the distributed antenna system is equal to or greater than the minimum allowed delay and
wherein a coverage area of communication from a first antenna of the first remote antenna unit is proportional to the first total delay.
39. The method of claim 38 , wherein the first inherent delay comprises at least one of a propagation delay between the host unit and the first remote antenna unit.
40. The method of claim 38 , further comprising transporting signals from the base station through the distributed antenna system via a physical medium.
41. The method of claim 38 , further comprising communicating digital baseband data between a service provider interface of the base station and the host unit of the distributed antenna system.
42. The method of claim 38 , further comprising communicating radio frequency signals between a service provider interface of the base station and the host unit of the distributed antenna system.
43. The method of claim 38 , further comprising:
configuring a distributed antenna system to have a second additional delay in addition to a second inherent delay of the distributed antenna system between the host unit and a second remote antenna unit; and
wherein a second total delay of the second additional delay and the second inherent delay of the distributed antenna system is equal to or greater than the minimum allowed delay.
44. A distributed antenna system comprising:
a host unit communicatively coupled to a first service provider interface which receives a first signal from the first service provider interface;
a first remote antenna unit communicatively coupled to the host unit;
wherein a base station to which the distributed antenna system is communicatively coupled is configured with a subscriber access timing window having a minimum allowed delay and a maximum allowed delay;
wherein the distributed antenna system is configured so that a first total delay between the host unit and the first remote antenna unit is equal to or greater than the minimum allowed delay; and
wherein a coverage area of communication from a first antenna of the first remote antenna unit is proportional to the first total delay.