CAPACITY OPTIMIZATION SUB-SYSTEM FOR DISTRIBUTED ANTENNA SYSTEM

• US 20150264582A1
• Filed: 10/05/2012
• Published: 09/17/2015
• Est. Priority Date: 10/05/2012
• Status: Active Grant

• Current Assignee: Andrew Wireless Systems GmbH (CommScope Holding Company, Inc.)
• Original Assignee: Andrew Wireless Systems GmbH (CommScope Holding Company, Inc.)
• Inventors: Brighenti, Samuele, Mini, Massimiliano
• Granted Patent: US 9,913,147 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 16/08 Load shedding arrangements
• CPC Class Codes: H04W 16/24 Cell structures
• CPC Class Codes: H04W 28/0861 between base stations
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

Certain aspects are directed to a capacity optimization sub-system for a distributed antenna system. The capacity optimization sub-system includes a switch matrix and a controller. The switch matrix includes variable attenuators and switches. The switch matrix can receive sectors from base stations. The switch matrix can provide the sectors to coverage zones. The controller can communicate with the switch matrix. The controller can determine that a number of wireless devices in one or more of the coverage zones is outside a specified range of threshold traffic levels. In response to determining that the number of wireless devices is outside the specified range of threshold traffic levels, the controller can configure one or more of the variable attenuators and corresponding switches to redistribute capacity among the coverage zones by, for example, increasing and/or decreasing capacity in one or more of the threshold

Claims

1. A capacity optimization sub-system for distributing capacity in a distributed antenna system, the capacity optimization sub-system comprising:

a switch matrix having a plurality of variable attenuators and a plurality of switches, the switch matrix configured to receive a plurality of sectors from a plurality of base stations and to provide the plurality of sectors to a plurality of coverage zones; and

a controller communicatively coupled to the switch matrix, the controller configured to;

determine that a number of wireless devices in one or more of the plurality of coverage zones is outside a specified range of threshold traffic levels, and

in response to determining that the number of wireless devices is outside the specified range of threshold traffic levels, configure one or more of the plurality of variable attenuators and one or more corresponding switches to redistribute capacity among the plurality of coverage zones.

2. The capacity optimization sub-system of claim 1,

wherein the one or more of the plurality of variable attenuators and the one or more corresponding switches are further configured to decrease capacity in a first set of coverage zones of the plurality of coverage zones by attenuating signals being provided from a first source of capacity to one or more wireless devices in the first set of coverage zones,

wherein the controller is configured to determine a rate of attenuation of the signals based on a traffic level in the first set of coverage zones, wherein the rate of attenuation is sufficient to induce the one or more wireless devices to switch to a second source of capacity.

3. The capacity optimization sub-system of claim 2,

wherein the one or more of the plurality of variable attenuators and the one or more corresponding switches are further configured to increase capacity in a second set of coverage zones by reducing attenuation of the signals being provided from the first source of capacity to one or more wireless devices in the second set of coverage zones,

wherein the controller is further configured to determine the second set of coverage zones in which capacity is increased based on traffic levels in the second set of coverage zones.

4. The capacity optimization sub-system of claim 1, wherein the switch matrix is further configured to distribute analog signals to one or more remote antenna units in each of the plurality of coverage zones.

5. The capacity optimization sub-system of claim 1, wherein the controller is configured to determine traffic levels by executing a scheduling algorithm stored on a computer readable medium accessible by the controller.

6. The capacity optimization sub-system of claim 1,

wherein the controller is further configured to establish a data link with one or more remote antenna units servicing the plurality of coverage zones,

wherein at least one remote antenna unit in each coverage zone comprises a signal detection device,

wherein the signal detection device is configured to communicate, via the data link, data describing traffic levels of wireless devices in communication with the at least one remote unit antenna, and

wherein the controller is configured to determine that the number of wireless devices is outside the specified range of threshold traffic levels based on the cumulative data received from the signal detection devices describing a traffic level in a respective coverage zone.

7. The capacity optimization sub-system of claim 6, wherein each signal detection device comprises an uplink signal sniffer.

8. The capacity optimization sub-system of claim 6, wherein each signal detection device comprises a frequency scanner.

9. The capacity optimization sub-system of claim 1, wherein the switch matrix is disposed in an intelligent point-of-interface system.

10. A distributed antenna system comprising:

a plurality of remote antenna units configured to provide service to a plurality of coverage zones, wherein at least one remote antenna unit in each coverage zone comprises a signal detection device; and

a capacity optimization sub-system comprising;

a switch matrix having a plurality of variable attenuators and a plurality of switches, the switch matrix configured to receive a plurality of sectors from a plurality of base stations and to provide the plurality of sectors to the plurality of coverage zones; and

a controller communicatively coupled to the switch matrix and to the plurality of remote antenna units, the controller configured to;

determine, based on the data received from each signal detection device describing a traffic level in a respective coverage zone, cumulative traffic levels in the plurality of coverage zones,

in response to determining that the cumulative traffic levels in a first set of coverage zones of the plurality of coverage zones is below a low threshold traffic level, configure one or more of the plurality of variable attenuators and one or more corresponding switches to decrease capacity in the first set of coverage zones, and

in response to determining that the cumulative traffic levels in a second set of coverage zones of the plurality of coverage zones is above a high threshold traffic level, configure one or more of the plurality of variable attenuators and one or more corresponding switches to increase capacity in the second set of coverage zones.

11. The distributed antenna system of claim 10, wherein the one or more of the plurality of variable attenuators and the one or more corresponding switches are configured to decrease capacity by attenuating signals being provided from a first source of capacity to one or more wireless devices in the plurality of coverage zones, wherein the controller is configured to determine a rate of attenuation of the signals based on traffic levels in the plurality of coverage zones, wherein the rate of attenuation of the signals is sufficient to induce the one or more wireless devices to switch to a second source of capacity.

12. The distributed antenna system of claim 10, wherein the controller is further configured to determine traffic levels by executing a scheduling algorithm stored on a computer readable medium accessible by the controller.

13. The distributed antenna system of claim 10, wherein each signal detection device comprises an uplink signal sniffer.

14. The distributed antenna system of claim 10, wherein each signal detection device comprises a frequency scanner.

15. The distributed antenna system of claim 10, wherein the switch matrix is disposed in an intelligent point-of-interface system of the distributed antenna system.

16. A method for optimizing capacity in a distributed antenna system, the method comprising:

determining, by a processor, that a number of wireless devices in one or more coverage zones receiving a plurality of sectors from a plurality of base stations is below a threshold corresponding to a low traffic level; and

in response to determining that the number of wireless devices is below the threshold corresponding to the low traffic level, configuring, by the processor, one or more variable attenuators and one or more corresponding switches of a switch matrix of the distributed antenna system to decrease capacity in the one or more coverage zones,

wherein decreasing capacity comprises attenuating signals from a first source of capacity in at least one coverage zone at a rate sufficient to induce one or more wireless devices in the at least one coverage zone to switch from the first source of capacity to a second source of capacity;

determining, by the processor, that the number of wireless devices in the one or more coverage zones receiving the plurality of sectors exceeds a threshold corresponding to a high traffic level; and

in response to determining that the number of wireless devices exceeds the threshold corresponding to the high traffic level, configuring, by the processor, the one or more variable attenuators and the one or more corresponding switches of the switch matrix of the distributed antenna system to increase capacity in the one or more coverage zones.

17. The method of claim 16,

wherein determining that the number of wireless devices in the one or more coverage zones is below the threshold corresponding to the low traffic level comprises:

requesting, by the processor, from at least one remote antenna unit in each coverage zone, the data identifying a respective number of wireless devices for the respective coverage zone, wherein the at least one remote antenna unit comprises a signal detection device configured to determine the respective number of wireless devices in the respective coverage zone, and

comparing, by the processor, the data identifying the respective number of wireless devices in the respective coverage zone to a minimum number of wireless devices stored in a computer-readable medium accessible by the processor; and

wherein determining that the number of wireless devices in the one or more coverage zones exceeds the threshold corresponding to the high traffic level comprises;

requesting, by the processor, from the at least one remote antenna unit in each coverage zone, the data identifying the respective number of wireless devices for the respective coverage zone, and

comparing, by the processor, the data identifying the respective number of wireless devices in the respective coverage zone to a maximum number of wireless devices stored in the computer-readable medium.

18. The method of claim 16, wherein determining that the number of wireless devices in the one or more coverage zones is below the threshold corresponding to the low traffic level comprises executing, by the processor, a scheduling algorithm stored in a computer-readable medium accessible by the processor, wherein the scheduling algorithm identifies one or more time periods associated with reducing capacity for the one or more coverage zones.

19. The method of claim 16, wherein determining that the number of wireless devices in the one or more coverage zones exceeds the threshold corresponding to the high traffic level comprises executing, by the processor, a scheduling algorithm stored in a computer-readable medium accessible by the processor, wherein the scheduling algorithm identifies one or more time periods associated with increasing capacity for the one or more coverage zones.

20. The method of claim 16, further comprising determining the threshold corresponding to the low traffic level and the threshold corresponding to the high traffic level based on one or more of an optimum power consumption or an optimum noise level of the distributed antenna system.