Method and apparatus for managing power in network interface modules

• US 20070162773A1
• Filed: 01/30/2007
• Published: 07/12/2007
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Moore, Timothy, Abhishek, Abhishek, Ruan, Jiandong, Ayyagari, Arun, Krantz, Anton, Geiger, Avi, Barkley, Warren
• Granted Patent: US 7,506,188 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3209 Monitoring remote activity, e.g. over telephone lines or network connections
• CPC Class Codes: G06F 1/325 Power saving in peripheral device
• CPC Class Codes: H04M 2250/06 including a wireless LAN interface
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0225 using monitoring of external events, e.g. the presence of a signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and system for managing power consumption in a portable computing device having a network interface module is presented. A power management module receives inputs from other modules and determines when the network interface module is to be put in a doze state for a predetermined number of beacon intervals to conserve power consumption in the network interface module. The network interface module in a device that is associated with a network is put in the doze state after an event has occurred including when a scan has been performed, after a delayed sleep timer has expired, and after a beacon transmission has been completed and no traffic is buffered for the device. The delayed sleep time is set based on the estimated round trip time of a packet.

Claims

1-44. -44. (canceled)

45. A method to send packets in a device having a network interface module operating in a power saving mode, the method comprising the steps of:

sending a packet to an access point;

setting a delay sleep timer to time out after a delay sleep time;

sending a message to the access point after the delay sleep timer has timed out to indicate the network interface module is entering a doze state in which a transmit and/or receive component of the network interface module is powered down; and

setting the network interface module to the doze state in response to the delayed sleep timer timing out.

46. The method of claim 45 further comprising the step of resetting the delay sleep timer if at least one other packet is being sent to the access point while the delay sleep timer is counting.

47. The method of claim 46 further comprising the step of determining a delay sleep time for each of the packet and the at least one other packet.

48. The method of claim 45 further comprising the step of determining the delay sleep time for the packet.

49. The method of claim 48 wherein the step of determining the delay sleep time includes determining an estimated round trip time.

50. The method of claim 49 wherein the step of determining the delay sleep time includes setting the delay sleep time to the estimated round trip time if the estimated round trip time is lower than a beacon interval time.

51. The method of claim 48 wherein the step of determining the delay sleep time includes setting the delay sleep time to a time less than a beacon interval time if the estimated round trip time is at least a beacon interval time.

52. The method of claim 45 wherein the network interface module is transmitting packets from a plurality of sessions, the method further comprising the steps of:

determining a maximum round trip transmission time for the plurality of sessions; and

setting the delay sleep time to the maximum round trip time.

53. The method of claim 52 wherein the step of setting the delay sleep time to the maximum round trip time comprises the steps of:

setting the delay sleep time to the maximum round trip time if the estimated round trip time is lower than a beacon interval time; and

setting the delay sleep time to a time less than a beacon interval time if the maximum round trip time is at least a beacon interval time.

60. The method of claim 45, wherein the step of setting a delay sleep timer to time out after a delay sleep time comprises determining a delay sleep time based at least in part on a session generating the packet.

54-59. -59. (canceled)

61. A computer-readable medium having computer-executable instructions for, when executed, controlling a wireless network-enabled computing device to perform steps comprising:

sending a packet to an access point;

setting a delay sleep timer to time out after a delay sleep time;

sending a message to the access point after the delay sleep timer has timed out to indicate the network interface module is entering a doze state in which a transmit and/or receive component of the network interface module is powered down; and

setting the network interface module to the doze state in response to the delayed sleep timer timing out.

62. The computer-readable medium of claim 61, wherein the computer-executable instructions, when executed, further control the wireless network-enabled computing device to perform steps comprising:

resetting the delay sleep timer if at least one other packet is being sent to the access point while the delay sleep timer is counting.

63. The computer-readable medium of claim 61, wherein the computer-executable instructions, when executed, further control the wireless network-enabled computing device to perform a step comprising:

determine the delay sleep time includes determining an estimated round trip time.

64. The computer-readable medium of claim 61, wherein the network interface module is transmitting packets from a plurality of sessions and the computer-executable instructions, when executed, further control the wireless network-enabled computing device to perform steps comprising:

determining a maximum round trip transmission time for the plurality of sessions; and

setting the delay sleep time to the maximum round trip time.

65. The computer-readable medium of claim 61, wherein the steps of sending a packet, setting a delay sleep timer, sending a message and the setting the network interface module to the doze state occur while the device is associated with the access point.

70. The network interface module of claim 65, wherein:

the power management module is further adapted to alternatively set the network interface module to the doze state until a subsequent beacon interval.

66. A network interface module for a wireless network-enabled computing device, the module comprising:

a transmit circuit adapted to send a packet to an second network enabled device with which the network enabled device is communicating;

a power management module having a delay sleep time, the power management module being adapted to;

set the delay sleep timer to time out a delay sleep time after the packet is sent;

send a message to the access point after the delay sleep timer has timed out, the message indicating that the network interface module is entering a doze state in which a transmit and/or receive component of the network interface module is powered down; and

set the network interface module to the doze state in response to the delay sleep timer timing out.

67. The network interface module of claim 66, wherein power management module is further adapted to:

reset the delay sleep timer if at least one other packet is being sent to the access point while the delay sleep timer is counting.

68. The network interface module of claim 66, further comprising:

a packet analyzer adapted to determine the delay sleep time based on an estimated round trip time of the packet.

69. The network interface module of claim 68, wherein the wireless network-enabled computing device is adapted to transmit packets from a plurality of sessions and the packet analyzer is adapted to determine a delay sleep time for each session.