Wireless Access Point Methods And Apparatus Using Dynamically-Activated Service Intervals

• US 20100246460A1
• Filed: 03/27/2009
• Published: 09/30/2010
• Est. Priority Date: 03/27/2009
• Status: Active Grant

• Current Assignee: Mcmaster University
• Original Assignee: Mcmaster University
• Inventors: Koutsakis, Polychronis, Smadi, Mohammed N., Todd, Terence Douglas, Kholaif, Ahmad Mohammad
• Granted Patent: US 8,194,576 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Methods and apparatus for controlling a wireless access point (AP) (e.g. a battery-powered wireless AP) for reduced power consumption are provided. In one illustrative example, the AP is adapted to provide communication access for end stations in one or more activated service intervals of each superframe. During operation, the AP changes the number of activated service intervals that are available to end stations for the communication access, as well as the durations of their active subinterval durations, in accordance with a change in traffic requirements. The AP regularly broadcasts data which indicates the activated service intervals that are made available to the mobile devices. A wireless transceiver of the AP is enabled during each activated service interval made available to the mobile devices, but the AP is placed in a power conservation mode during each deactivated service interval provided in between the activated service intervals. The AP may also be placed in the power conservation mode during inactive subintervals of each activated service interval.

Claims

1. A method for controlling a wireless access point adapted to provide communication access for communication devices during one or more service intervals of each one of a plurality of superframes, the method comprising the acts of:

in response to a change in a traffic requirement for communication devices operating via the wireless access point;

changing, in accordance with the change in the traffic requirement, the number of activated service intervals in the superframe that are available to the communication devices for the communication access;

transmitting, to the communication devices, data which indicates the activated service intervals in the superframe that are made available to the communication devices for the communication access;

causing a wireless transceiver of the wireless access point to be enabled for communications during each said activated service interval; and

causing the wireless access point to be placed into a power conservation mode during each power conservation interval provided in between said activated service intervals.

2. The method of claim 1, wherein the number of activated service intervals has a relationship with the traffic requirement such that as the traffic requirement increases, the number of service intervals increase.

3. The method of claim 1, further comprising:

causing the wireless transceiver to be enabled for communications during an active subinterval of said activated service interval; and

causing the wireless transceiver to be placed into the power conservation mode during an inactive subinterval of said activated service interval.

4. The method of claim 1, further comprising:

in response to the change in traffic requirement;

changing, in accordance with the change in the traffic requirement, the duration of at least one active subinterval of an activated service interval for the communication access, the duration having a relationship with the traffic requirement such that as the traffic requirement increases, the duration of the at least one service interval increases.

5. The method of claim 1, wherein the communication access comprises contention-based communication access or polling-based communication access for the communication devices.

6. The method of claim 1, wherein the act of transmitting comprises the further act of broadcasting identifiers of the activated service intervals that are available to the communication devices for the communication access.

7. The method of claim 1, wherein the act of transmitting comprises the further act of broadcasting data indicative of boundaries or durations of the activated service intervals that are available to the communication devices for the communication access.

8. The method of claim 1, further comprising:

receiving, from one of the communication devices, a traffic specification (TSPEC); and

identifying the change in the traffic requirement based on data in the traffic specification.

9. The method of claim 1, further comprising:

receiving, from one of the communication devices, a request for communications; and

assigning one or more service intervals exclusively for the communications of the communication device.

10. The method of claim 1, wherein the communication access comprises one of contention-based communication access or polling-based access.

11. The method of claim 1, which is performed by computer instructions stored in a computer readable medium and executable on one or more processors of the wireless access point.

12. A wireless access point, comprising:

electrical components;

a battery power interface adapted for coupling to a battery power source for supplying electrical power to the electrical components;

the electrical components including;

at least one wireless transceiver;

an antenna coupled to the at least one wireless transceiver;

one or more processors coupled to the at least one wireless transceiver;

the one or more processors being operative with the wireless transceiver to;

provide communication access for communication devices in one or more activated service intervals of each one of a plurality of superframes;

in response to a change in a traffic requirement for the communication devices operating via the wireless access point;

change, in accordance with the change in the traffic requirement, the number of said activated service intervals in the superframe that are available to the communication devices for the communication access;

broadcast, to the communication devices, data which indicates the activated service intervals in the superframe that are made available to the communication devices for the communication access;

causing the wireless transceiver to be enabled for communications during each said activated service interval; and

causing the wireless access point to be placed into a power conservation mode during each power conservation interval provided in between said activated service intervals.

13. The wireless access point of claim 12, wherein the number of activated service intervals has a relationship with the traffic requirement such that as the traffic requirement increases, the number of service intervals increase.

14. The wireless access point of claim 12, wherein the one or more processors are further operative to:

in response to the change in traffic requirement;

change, in accordance with the change in the traffic requirement, the duration of at least one active subinterval of an activated service interval for the communication access, the duration having a relationship with the traffic requirement such that as the traffic requirement increases, the duration of the at least one service interval increases.

15. The wireless access point of claim 12, wherein the one or more processors are further operative to broadcast identifiers of the service intervals that are available to the communication devices for the communication access.

16. The wireless access point of claim 12, wherein the one or more processors are further operative to broadcast data indicative of boundaries or durations of the activated service intervals that are available to the mobile devices for the communication access.

17. The wireless access point of claim 12, wherein the one or more processors are further operative to:

receive, from one of the communication devices, a traffic specification; and

identify the change in the traffic requirement based on data in the traffic specification.

18. The wireless access point of claim 12, wherein the one or more processors are further operative to:

receive, from one of the communication devices, a request for communications; and

assign one or more service intervals exclusively for the communications of the communication device.

19. The wireless access point of claim 12, which is adapted to connect with and be part of a wireless local area network (WLAN) and operates in accordance with IEEE 802.11.

20. A method in a mobile communication device for communicating with a wireless access point, the method comprising:

receiving, from the wireless access point, data which indicates one or more activated service intervals in the superframe that are made available to mobile devices for communication access;

when communications are required;

accessing, during said one or more activated service intervals, the wireless access point using the communication; and

refraining from accessing the wireless access point during each power conservation interval provided in between the activated service intervals.