Mobile station having enhanced standby mode

• US 6,067,460 A
• Filed: 04/07/1997
• Issued: 05/23/2000
• Est. Priority Date: 05/23/1996
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Ranta, Jukka, Jokinen, Harri, Alanara, Seppo, Pirila, Hannu
• Primary Examiner(s): Trost, William G.
• Assistant Examiner(s): LEGREE, TRACY MICHELLE
• Application Number:
  US08/835,240
• Time in Patent Office: 1,142 Days
• Field of Search: 455/574, 455/450, 455/161.3, 455/343, 455/422, 455/483, 455/434, 455/441, 455/444
• US Class Current: 455/574
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

When a mobile station (10) is in a DCCH camping state it monitors its assigned page frame. After making RSSI and possibly also Bit Error Rate/Word Error Rate (BER/WER) measurements the mobile station monitors the rate of change of the RSSI. If the rate of change is small and remains so, the mobile station is assumed to be in a stationary state. After determining that it is stationary, the mobile station may give an audible alert and/or display a message to request the user to confirm that the mobile station is (and will remain) stationary. When in the stationary state the mobile station inhibits making neighbor channel measurements for DCCH reselection. The mobile station continues to monitor its assigned page frame within an assigned digital control channel and to measure its own channel RSSI and possibly also the BER/WER. If these values subsequently indicate that the mobile station is no longer stationary, the mobile station immediately resumes all neighbor channel measurements.

Claims

1. A method for operating a wireless mobile station in a standby mode, comprising the steps of:

periodically making received signal strength measurements of a currently assigned digital control channel and at least one other currently non-assigned channel;

detecting that the mobile station has become stationary when a change over time in the received signal strength of the currently assigned digital control channel falls below a predetermined threshold;

verifying that the mobile station has become stationary;

terminating the measurements of the at least one other currently non-assigned channel;

detecting that the mobile station is no longer stationary when a change over time in the received signal strength of the currently assigned digital control channel rises above the predetermined threshold; and

initiating the measurements of the at least one other currently non-assigned channel;

wherein

the step of terminating the measurements of the at least one other currently non-assigned channel is also executed upon an occurrence of a detection by the mobile station that a cell serving the mobile station is a predetermined cell.

2. A method as set forth in claim 1, wherein the step of verifying includes a step of prompting at least one of a user and a base station to verify that the mobile station has become stationary.

3. A method as set forth in claim 1, wherein at least the step of detecting that the mobile station has become stationary includes the steps of:

operating a motion sensor; and

detecting that the mobile station has become stationary based at least in part on an output of the motion sensor.

4. A method as set forth in claim 1, wherein at least the step of detecting that the mobile station has become stationary includes the steps of:

operating a multi-axis acceleration transducer; and

detecting that the mobile station has become stationary based at least in part on an output of the acceleration transducer.

5. A method as set forth in claim 1, wherein a value of the predetermined threshold is adaptively varied by one of the mobile station or a base station.

6. A method as set forth in claim 1, wherein at least one of the steps of detecting further considers at least one of a measured bit error rate or a measured word error rate.

7. A method of reducing the power consumption of a mobile station when operating in an idle mode, comprising the steps of:

detecting, with the mobile station, a fulfillment of at least one first predetermined criterion when operating in the idle mode;

in response to the detection of the fulfillment of the at least one first predetermined criterion, entering a power saving mode that operates by reducing a use of a receiver of the mobile station to receive signals from one or more cells that border a cell that currently serves the mobile station;

detecting, with the mobile station, a fulfillment of at least one second predetermined criterion when operating in the power saving mode; and

in response to the detection of the fulfillment of the at least one second predetermined criterion, exiting the power saving mode;

wherein

the at least one first predetermined criterion is comprised of an occurrence of a detection by the mobile station that a cell serving the mobile station is a predetermined cell.

8. A method as set forth in claim 7, wherein the at least one first or second predetermined criterion is a presence of an input command entered by a user.

9. A method as set forth in claim 7, wherein the at least one second predetermined criterion is an occurrence of the mobile station exiting a cell wherein the power saving mode was activated.

10. A method as set forth in claim 7, wherein the at least one second predetermined criterion is an occurrence of a timeout condition indicated by a timer means.

11. A method as set forth in claim 7, wherein the at least one second predetermined criterion is an occurrence of a condition wherein a RSSI level of the serving cell decreases by some predetermined amount.

12. A method as set forth in claim 7, wherein the at least one first predetermined criterion is an occurrence of an expiration of a predetermined period of time after a cell reselection operation has been performed.

13. A method as set forth in claim 7, wherein the at least one first predetermined criterion is an occurrence of a first predetermined time of day, and wherein the at least one second predetermined criterion is an occurrence of a second predetermined time of day.

14. A method for operating a wireless mobile station in a standby mode to conserve battery power, comprising the steps of:

initiating a neighboring cell search task; and

subsequently operating a controller of the mobile station to execute the following steps,

receiving a paging block;

calculating a motion indicator based at least in part on measured received signal strength indicator (RSSI) levels, including RSSI levels measured from neighboring cells;

comparing the motion indicator to a threshold value;

in accordance with a result of the step of comparing the motion indicator to the threshold value, performing one of continuing to make RSSI measurements of neighboring cells or terminating the making of RSSI measurements of neighboring cells, where

an amount of RSSI measurements is a number of neighboring cell signal level samples per paging block reception, where the neighboring cell search task searches for adjacent cells from which cell synchronization data has not been received, and where refreshing procedures are periodically performed to receive cell synchronization data from neighboring cells from which cell synchronization data was previously received.