Method and apparatus for power saving in a mobile terminal with established connections

• US 6,463,307 B1
• Filed: 08/14/1998
• Issued: 10/08/2002
• Est. Priority Date: 08/14/1998
• Status: Expired due to Term

• Current Assignee: Wi-Fi One, LLC (Inception Holdings, LLC)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Larsson, Peter, Larsson, Mikael
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): Milord, Marceau
• Application Number:
  US09/134,738
• Time in Patent Office: 1,516 Days
• Field of Search: 455/422, 455/424, 455/425, 455/67.1, 455/67.4, 455/343, 455/574, 455/575
• US Class Current: 455/574
• CPC Class Codes: H04B 1/1615 Switching on; Switching off, e.g. remotely battery saving circuits associated with selective call operation H04W52/00; details of power consumption reduction in a PLL, H03L7/0802, H03L7/14, H03L2207/08, H03L2207/18; muting amplifiers by gain control see H03G3/34
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Power consumption of a mobile terminal is reduced by providing a system wherein a base station specifies a time period, at the end of which a mobile terminal that is hibernating in a power-saving mode will listen for paging messages from the base station. If no paging messages are present, then the mobile terminal continues hibernating, thus conserving battery power by not communicating with the base station. Either the base station or the mobile terminal can initiate a process to transfer the mobile terminal from an awake mode to a hibernating mode. In accordance with another embodiment of the invention for use in systems that require frequent connectivity testing, an agent can be provided within the base station to answer connectivity test inquiries on behalf of the mobile terminal. The mobile terminal can communicate periodically with the base station to update information that the agent uses to respond to the test inquiries.

Claims

1. A method for reducing power consumption in a first mobile terminal having an established wireless communication connection with a base station, comprising the steps of:

sending a hibernation request from the first mobile terminal to the base station;

determining a hibernation request response, the response comprising a parameter indicating a length of a time period;

sending the hibernation request response from the base station to the mobile terminal;

changing the first mobile terminal from an awake state to a hibernation state in accordance with parameters in the hibernation request response;

beginning the time period when changing to the hibernation state;

listening for paging messages from the base station at the end of the time period;

determining when the first mobile terminal is in the hibernation state;

buffering at least one data packet at the base station for later transfer to the first mobile terminal while the first mobile terminal is in the hibernation state;

receiving a paging message from the base station at the first mobile terminal when the first mobile terminal is listening for paging messages;

changing the first mobile terminal from the hibernation state to the awake state when receiving the paging message;

receiving a paging acknowledgment signal from the first mobile terminal at the base station;

in response to the base station receiving the paging acknowledgment signal, recognizing that the first mobile terminal has changed to the awake state;

transferring the buffered at least one data packet from the base station to the first mobile terminal in response to the paging acknowledgment signal.

2. The method of claim 1 further comprising the steps of:

sending a capacity request from the first mobile terminal to the base station;

automatically changing the first mobile terminal from the hibernation state to the awake state when sending the capacity request;

recognizing that the first mobile terminal has changed to the awake state when receiving the capacity request at the base station;

receiving an uplink slot assignment from the base station at the first mobile terminal; and

sending a data packet from the first mobile terminal to the base station via the assigned uplink slot.

3. A method for reducing power consumption in a first mobile terminal having an established wireless communication connection with a base station, comprising the steps of:

sending a hibernation request from the first mobile terminal to the base station;

determining a hibernation request response, the response comprising a parameter indicating a length of a time period;

sending the hibernation request response from the base station to the mobile terminal;

changing the first mobile terminal from an awake state to a hibernation state in accordance with parameters in the hibernation request response;

beginning the time period when changing to the hibernation state;

listening for paging messages from the base station at the end of the time period;

determining when the time period has expired;

upon expiration of the time period, determining whether a paging message from the base station is present;

receiving the paging message at the first mobile terminal when it is determined that the paging message is present;

acknowledging the paging message with an acknowledgment signal;

changing the first mobile terminal from the hibernation state to the awake state when acknowledging the paging message;

recognizing that the first mobile terminal has changed to the awake state when receiving the acknowledgment signal at the base station; and

receiving at least one data packet from the base station.

4. The method of claim 3, further comprising the steps of keeping the first mobile terminal in the hibernation state when it is determined that no paging messages are present and the time period has expired, and restarting the time period.

5. The method of claim 4, further comprising the step of periodically sending a report from the mobile terminal to the base station while the mobile terminal remains in the hibernation state.

6. A method for reducing power consumption in a first mobile terminal having an established wireless communication connection with a base station, wherein the base station is connected to a network that periodically sends connectivity test messages to the first mobile terminal, and the base station includes an agent having a database that mirrors a managed information base of the first mobile terminal, the method comprising the steps of:

sending a hibernation request from the first mobile terminal to the base station;

determining a hibernation request response, the response comprising a parameter indicating a length of a time period;

sending the hibernation request response from the base station to the mobile terminal;

changing the first mobile terminal from an awake state to a hibernation state in accordance with parameters in the hibernation request response;

beginning the time period when changing to the hibernation state;

listening for paging messages from the base station at the end of the time period;

intercepting a connectivity test message from the network intended for the first mobile terminal;

replying to the connectivity test message using the agent;

requesting updated information regarding the first mobile terminal;

receiving updated information from the first mobile terminal; and

updating the agent database using the received updated information.

7. The method of claim 6, wherein the step of updating the agent database is performed less often than the step of receiving the connectivity test message.

8. A method for reducing power consumption in a first mobile terminal having an established wireless communication connection with a base station, wherein the base station is connected to a network that periodically sends connectivity test messages to the first mobile terminal, and the base station includes an agent having a database that mirrors a managed information base of the first mobile terminal, the method comprising the steps of:

sending a hibernation request from the first mobile terminal to the base station;

determining a hibernation request response, the response comprising a parameter indicating a length of a time period;

sending the hibernation request response from the base station to the mobile terminal;

changing the first mobile terminal from an awake state to a hibernation state in accordance with parameters in the hibernation request response;

beginning the time period when changing to the hibernation state;

listening for paging messages from the base station at the end of the time period;

intercepting a connectivity test message from the network intended for the first mobile terminal;

replying to the connectivity test message using the agent;

determining whether it is time to send updated information regarding the first mobile terminal to the agent;

when it is time to send updated information regarding the first mobile terminal to the agent, automatically sending the updated information from the mobile terminal to the agent; and

updating the agent database using the received updated information.

9. The method of claim 8, wherein the step of automatically sending is performed less often than the step of receiving the connectivity test message.