EVOLUTIONARY ALGORITHMS FOR GEOGRAPHIC LOAD BALANCING USING A DISTRIBUTED ANTENNA SYSTEM

• US 20140057627A1
• Filed: 02/19/2013
• Published: 02/27/2014
• Est. Priority Date: 02/17/2012
• Status: Active Grant

• Current Assignee: Dali Wireless Inc. (Dali Systems Co., Ltd.)
• Original Assignee: Dali Systems Co., Ltd.
• Inventors: Stapleton, Shawn Patrick, Hejazi, Seyed Amin
• Granted Patent: US 9,148,839 B2
• Time in Patent Office: Days
• US Class Current: 455/424
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 36/304 due to measured or perceived resources with higher communication quality
• CPC Class Codes: H04W 40/14 based on stability
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

Methods and apparatuses are presented for balancing non-uniformly distributed network traffic in a wireless communications system having a plurality of digital remote units (DRUs). In some embodiments, a method comprises partitioning the plurality of DRUs into a plurality of DRU sectors, and dynamically repartitioning the plurality of DRU sectors depending on traffic conditions in at least one of the DRU sectors, such that the repartitioning satisfies at least one of a soft capacity constraint or a hard capacity constraint. The dynamic repartitioning may be based on at least one optimization algorithm.

Claims

1. A method for balancing non-uniformly distributed network traffic in a wireless communications system having a plurality of digital remote units (DRUs), the method comprising:

a) providing a digital access unit (DAU) associated with a plurality of sectors of a base station;

b) providing a plurality of DRUs associated with the DAU;

c) partitioning the plurality of DRUs into a plurality of DRU sectors;

d) measuring a number of blocked calls associated with the plurality of DRU sectors;

e) determining that the number of blocked calls is greater than a predetermined threshold; and

f) iterating using at least elements (c) through (e).

2. The method of claim 1 wherein iterating comprises utilizing at least one optimization algorithm.

3. The method of claim 2 wherein the at least one optimization algorithm is at least one of a Genetic Algorithm (GA) or an Estimation Distribution Algorithm (EDA).

4. The method of claim 2 wherein the at least one optimization algorithm includes at least one linear programming model.

5. The method of claim 1 wherein each of the DRU sectors comprises connected DRUs.

6. The method of claim 1 further comprising determining a total number of licenses/sources assigned to a virtual base station (VBS).

7. A method for balancing non-uniformly distributed network traffic in a Distributed Antenna System (DAS), the method comprising:

a) providing a digital access unit (DAU) associated with a plurality of sectors of a base station;

b) providing a plurality of Digital Remote Units (DRUs) associated with the DAU;

c) partitioning the plurality of DRUs into a plurality of DRU sectors;

d) measuring at least one metric for traffic conditions associated with the plurality of DRU sectors;

e) comparing the at least one metric to a predetermined threshold;

f) determining that iteration of partitioning is warranted; and

g) iterating on at least elements (c) through (e).

8. The method of claim 7 wherein the at least one system metric comprises at least one of minimizing call handoffs or maximizing a compactness index of each of the DRU sectors.

9. The method of claim 7 wherein each of the plurality of DRU sectors is substantially compact.

10. The method of claim 7 wherein the at least one metric comprises a maximum number of users associated with a predetermined signal to noise ratio (SNR).

11. The method of claim 7 wherein iterating comprises utilizing at least one optimization algorithm.

12. The method of claim 11 wherein the at least one optimization algorithm is at least one of a Genetic Algorithm (GA) or an Estimation Distribution Algorithm (EDA).

13. The method of claim 11 wherein the at least one optimization algorithm includes at least one linear programming model.

14. The method of claim 7 wherein each of the DRU sectors comprises connected DRUs.

15. A Distributed Antenna System (DAS) comprising:

one or more Digital Access Units (DAUs);

a plurality of Digital Remote Units (DRUs) coupled to the one or more DAUs;

a data processor coupled to the plurality of DRUs and comprising a non-transitory computer-readable storage medium comprising a plurality of computer-readable instructions tangibly embodied on the computer-readable storage medium, which, when executed by the data processor, provide for balancing of network traffic, the plurality of instructions comprising;

a) instructions that cause the data processor to partition the plurality of DRUs into a plurality of DRU sectors;

b) instructions that cause the data processor to measure at least one system metric for traffic conditions associated with the plurality of DRU sectors;

c) instructions that cause the data processor to compare the at least one system metric to a predetermined threshold; and

d) instructions that cause the data processor to determine that the at least one system metric is greater than the predetermined threshold; and

e) iterating at least elements (a) through (d).

16. The DAS of claim 15 wherein the at least one system metric comprises a number of blocked calls.

17. The DAS of claim 15 wherein the at least one system metric comprises a number of call handoffs between two of the plurality of DRU sectors.

18. The DAS of claim 15 wherein each of the DRU sectors comprises connected DRUs.

19. The DAS of claim 15 wherein each of the plurality of DRU sectors is substantially compact.

20. The DAS of claim 15 wherein iterating comprises utilizing at least one optimization algorithm.