Method and apparatus for network wide adaptive resource allocation for OFDMA/TDMA networks

• US 8,284,715 B2
• Filed: 12/22/2006
• Issued: 10/09/2012
• Est. Priority Date: 12/22/2005
• Status: Active Grant

• Current Assignee: WiChorus, Inc. (Infinera Corp.)
• Original Assignee: WiChorus, Inc. (Infinera Corp.)
• Inventors: Jalil, Rehan, Ergen, Mustafa, Mak, Tony
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Lau, Yungsang
• Application Number:
  US11/644,706
• Publication Number:
  US 20090080375A1
• Time in Patent Office: 2,118 Days
• Field of Search: 370328-330
• US Class Current: 370/328
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
• CPC Class Codes: H04W 72/563 of the wireless resources

Abstract

The disclosure proposes an adaptive resource allocation in a network. A resource is divided into Blocks and each base station is assigned a Block for its subscribers that are in the interference region, and another Block for its subscribers that are not in the interference region. Blocks other than these two are not used by the base station. Bordering base stations does not use the same Block if they have any subscribers in the shared interference region. The disclosure proposes a resource sizing along with load balancing scheme. The resource sizing is adaptable and may change over time according to topology.

Claims

1. A method for allocating network wide adaptive resources, comprising:

providing a plurality of base stations each including a micro scheduler having traffic allocation logic to allocate an orthogonal frequency-division multiple-access (OFDMA) frame;

providing a plurality of subscribers in communication with the plurality of base stations;

providing a central controller in communication with the plurality of base stations, the central controller including a macro level scheduler configured to police traffic forwarded to each base station, the micro scheduler and the macro level scheduler controlling and optimizing radio frequency and backhaul the network wide adaptive resources in unison;

identifying subscribers in a first overlapping region of two or more base stations by the central controller;

assigning a second region in the OFDMA frame to a particular base station; and

blocking out the second region for other base stations in conflict with the particular base station.

3. The method of claim 1, further comprising assigning the network wide adaptive resources to the plurality of base stations by partitioning the network wide adaptive resources into blocks and assigning the blocks to the plurality of base stations.

4. The method of claim 3, wherein the network wide adaptive resources are partitioned into the blocks of equal sizes.

5. The method of claim 3, wherein partitioning the network wide adaptive resources into the blocks comprises:

determining a total cost for a block by summing up a cost of each subscriber assigned to the block;

determining a total cost of the network by summing up the cost of each subscriber in the network;

determining a scaling factor by dividing the total cost of the block by the total cost of the network; and

determining a size of the block by multiplying the network wide adaptive resources of the network by the scaling factor of the block.

6. The method of claim 5, further comprising receiving from the micro scheduler an average utilization of the block used by the subscribers attached to the particular base station and resizing the block to meet a traffic demand.

7. The method of claim 5, further comprising receiving from the micro scheduler an average utilization of a block used by the subscribers attached to the particular base station and allocating one or more subscribers to a different base station to meet the traffic demand.

2. A network comprising:

a central controller;

a plurality of base stations to communicate with the central controller; and

a plurality of subscribers to communicate with at least one base station using an orthogonal frequency-division multiple-access (OFDMA) protocol;

the at least one base station including a micro scheduler having a traffic allocation logic to allocate an OFDMA frame, the central controller including a macro level scheduler configured to police traffic that is forwarded to each of the base stations, the micro scheduler and macro level scheduler configured to control and optimize radio frequency and backhaul network wide adaptive resources by being configured to;

identify subscribers in a first overlapping region of two or more base stations;

assign a second region in the OFDMA frame to a particular base station; and

block out the second region for other base stations in conflict with the particular base station.

8. The network of claim 2, wherein the micro scheduler allocates a minimum bandwidth for voice, video and data transmissions in the OFDMA frame and allocates remaining bandwidth to an OFDA frame pool.

9. The network of claim 8, wherein the micro scheduler allocates bandwidth from the OFDMA frame pool when the minimum bandwidth is filled.

10. A method for managing adaptive resources in a communication network comprising:

identifying one or more subscribers in an interference region of a base station, the interference region being an area which is in a communication range of more than one base station;

partitioning the adaptive resources into a plurality of blocks;

assigning a first block to the base station for the one or more subscribers which are in the interference region;

assigning a second block to the base station for the subscribers which are not in the interference region;

assigning the one or more subscribers in the interference region to the base station; and

blocking the first block for the other base stations in the interference region.

11. The method of claim 10, wherein identifying the one or more subscribers in the interference region of the base station, comprises:

creating a connectivity map for all base stations and all subscribers in the communication network; and

identifying the one or more subscribers, in the connectivity map, which are in a communication range of more than one base station.

12. The method of claim 10, further comprising determining a cost weight of each of the one or more subscribers.

13. The method of claim 12, wherein the cost weight of each of the one or more subscribers is function of receive/transmit signal strength and traffic demand.

14. The method of claim 12, wherein the cost weight of each of the one or more subscribers is average traffic demand for each subscriber divided by the highest available rate of the subscriber.

15. The method of claim 10, wherein assigning the one or more subscribers in the interference region to the base station comprises:

estimating an occupancy of blocks assigned to the base stations which are in communication range of the one or more subscribers; and

assigning the one or more subscribers to a particular base station based on the estimated occupancy of the blocks.

16. The method of claim 15, wherein assigning the one or more subscribers to the particular base station based on the estimated occupancy comprises:

if the estimated occupancy of the blocks assigned to the base stations are empty then assigning the one or more subscribers to the particular base station assigned to a block having minimum number of the base stations.

17. The method of claim 15, wherein assigning the one or more subscriber to the particular base station based on the estimated occupancy comprises:

if the estimated occupancy of the blocks have enough space to accommodate the subscriber, assigning the subscriber to the particular base station attached to the block with a maximum available space.

18. The method of claim 15, wherein assigning the one or more subscribers to the particular base stations based on the estimated occupancy comprises:

if the estimated occupancy of the blocks does not have enough space to accommodate the one or more subscribers, assigning the one or more subscribers to the particular base station based on overall network utilization; and

resizing the blocks of the communication network.

19. The method of claim 18, wherein the overall network utilization is calculated as minimum of (M*(C−

(Bi-Bi*))) wherein, M is a number of base stations attached to block i, C is a cost weight of the subscriber, Bi is an actual occupancy of the block Bi, and Bi* is an estimated occupancy of the block Bi.

20. The method of claim 10, further comprising:

receiving periodic reports by a central controller for an utilization of the blocks used by the terminals attached to the base station; and

resizing the blocks based on the utilization of the blocks, when the utilization reaches a predefined limit or the utilization is unbalanced.