System and method for performance enhancement in heterogeneous wireless access network employing distributed antenna system

• US 9,020,555 B2
• Filed: 04/04/2011
• Issued: 04/28/2015
• Est. Priority Date: 04/05/2010
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Venkatraman, Shankar, Sheikh, Khurram P.
• Primary Examiner(s): Alam, Fayyaz
• Application Number:
  US13/079,558
• Publication Number:
  US 20110244914A1
• Time in Patent Office: 1,485 Days
• Field of Search: 455/522, 455 69- 70, 370315-320
• US Class Current: 455/522
• CPC Class Codes: H04W 24/06 Testing, supervising or monitoring using simulated traffic
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A system and method for dynamically optimizing the performance of indoor distributed antenna systems communicate to user equipment is disclosed. The user equipment measures information describing the downlink signals such as the downlink data rates, the quality of the received signal, and the location of the user equipment. A service module collects this information and determines an optimized power level for each of the antenna units. The service module may optimize only one antenna unit power level or a subset of the antenna units within the distributed antenna system in a preferred embodiment. One or more of the antenna units then transmits downlink signals with the optimized power levels. The optimized power level may be less than the initial power level in a preferred embodiment. As a result, the performance of the indoor distributed antenna systems is enhanced.

Claims

1. A method for optimizing downlink transmission power of a distributed antenna system, comprising:

providing a common downlink signal to a plurality of separate antenna units in a distributed antenna system; and

,

varying gain of one or more of the antenna units to enhance system performance based on collected user information.

2. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, further comprising collecting information describing the downlink signals from User Equipment (UE) including peak data rates of the downlink signals reported by the UE.

3. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 2, wherein collecting information further comprises:

collecting maximum sustainable data rates of the downlink signals reported by the UE; and

,

collecting the number of UEs having a QOS (Quality of Service) exceeding a QOS threshold.

4. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, wherein varying the gain of one or more of the antenna units comprises reducing gain of one or more antenna units to reduce multipath interference.

5. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, wherein varying the gain of the antenna units comprises varying a total gain of the distributed antenna system.

6. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, wherein varying the gain of one or more of the antenna units comprises varying a link gain of an individual antenna unit.

7. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 1, wherein the antenna units are grouped in indoor spaces separated by internal walls and wherein varying the gain of one or more of the antenna units comprises independently varying the gain of groups of the antenna units.

8. A method for optimizing downlink transmission power of a distributed antenna system, comprising:

transmitting common downlink signals having a first power level from a first antenna unit and a second antenna unit to User Equipment (UE), wherein the first antenna unit and the second antenna unit are physically separated;

collecting information describing the downlink signals reported by the UE;

determining when a downlink transmission power of the first antenna unit and second antenna unit should be updated based on the collected information; and

,

transmitting downlink signals having a second power level from the first antenna unit and the second antenna unit.

9. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 8, wherein collecting information describing the downlink signals comprises:

collecting downlink data rates of the downlink signals reported by the UE;

collecting signal quality information of the downlink signals reported by the UE; and

,

collecting location information reported by the UE.

10. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 9, wherein determining when a downlink transmission power of the first antenna unit and second antenna unit should be updated comprises:

estimating a current average capacity based on the collected information; and

,

comparing the current average capacity to a prior average capacity.

11. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 10, wherein the second power level is less than the first power level when the current average capacity is less than the prior average capacity.

12. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 10, wherein the second power level is greater than the first power level when the current average capacity is greater than the prior average capacity.

13. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 10, further comprising:

comparing the second power level to a maximum power threshold; and

,

when the second power level exceeds the maximum power level, reducing the second power level to the first power level.

14. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 9, wherein collecting information describing the downlink signals further comprises:

collecting peak data rates of the downlink signals reported by the UE;

collecting maximum sustainable data rates of the downlink signals reported by the UE; and

,

collecting the number of UEs having a QOS (Quality of Service) exceeding a QOS threshold.

15. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 14, wherein determining when a downlink transmission power of the first antenna unit and second antenna unit should be updated further comprises:

estimating a current average capacity based on the collected information; and

,

comparing the current average capacity to a prior average capacity.

16. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 8, wherein the first antenna unit and the second antenna unit are located indoors.

17. The method for optimizing the downlink transmission power of a distributed antenna system as set out in claim 8, wherein the downlink signal comprises a single sector carrier signal.

18. A distributed antenna system, comprising:

a distributed antenna system service module providing a downlink signal; and

a first antenna unit and a second antenna unit coupled to said distributed antenna system service module by transmission cables to receive said downlink signal and configured for wirelessly transmitting said downlink signal, wherein the first antenna unit and the second antenna unit are physically separated;

wherein said distributed antenna system service module is configured for controlling the transmission power levels of the first and second antenna units based on collected information from a plurality of User Equipment (UEs) receiving the downlink signals from the antenna units and transmitting uplink information to the antenna units.

19. The distributed antenna system as set out in claim 18, wherein the first and second antenna units are located indoors and cover separate service areas of a single space.

20. The distributed antenna system as set out in claim 19, further comprising:

a third antenna unit and a fourth antenna unit, coupled to said distributed antenna system service module by transmission cables and configured for wirelessly transmitting said downlink signal, wherein the third antenna unit and the fourth antenna unit are physically separated in a second space separated by walls from the first and second antenna units; and

,

wherein the distributed antenna system service module is configured for controlling the transmission power levels of the third and fourth antenna units based on collected information from a plurality of User Equipment (UEs) receiving the downlink signals from the third and fourth antenna units and transmitting uplink information to the antenna units in said second space.