Title of Invention

METHOD FOR CONSERVING BATTERY POWER IN A MOBILE STATION DURING EMERGENCY SERVICE AND NO SERVICE PERIOD

Abstract The present invention relates to a digital cellular radio communication system, and more particularly to a method for conserving battery power in a mobile station when the mobile station is scanning for networks during emergency and no service period. More particularly the present invention relates to method for conserving battery power in a mobile station during Emergency Service and No Service period. This invention explains a method for conserving battery power in a mobile station during emergency service comprising the steps of: storing the location area identity information elements Cell Identity, Location Area code and PLMN information; comparing the Location area identity information elements with the previously stored identity information elements; and estimating the time of background scanning based on the rate of change of said location area identity information elements, number of attempts and time period took to change from one information element to another.
Full Text FORM 2
THE PATENTS ACT, 1970
[39 of 1970]
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(Section 10; Rule 13)
METHOD FOR CONSERVING BATTERY POWER IN A MOBILE STATION DURING EMERGENCY SERVICE AND NO SERVICE PERIOD
SAMSUNG INDIA SOFTWARE OPERATIONS PRIVATE Ltd.
BAGMANE LAKEVIEW, BLOCK 'B',
No. 66/1, BAGMANE TECH PARK,
C V RAMAN NAGAR,
BYRASANDRA,
BANGALORE - 560093
A wholly owned subsidiary of Samsung Electronics Company Limited, Korea,
[an Indian Company]
The following Specification particularly describes the invention and the
manner in which it is to be performed
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FIELD OF INVENTION
The present invention relates to a digital cellular radio communication system, and more particularly to a method for conserving battery power in a mobile station when the mobile station is scanning for networks during emergency and no service period. More particularly, the present invention relates to method for conserving battery power in a mobile station during Emergency Service and No Service period.
DESCRIPTION OF RELATED ART
Currently mobile station is following the fixed sleep time interval (time interval between scans) for scanning the networks during emergency or no service.
Constantly repeating the scans for networks provides the mobile station with the best chance of rapidly acquiring a service. However, minimizing the time interval between scans, or maximizing the scan rate, causes the highest power consumption and optimization of the network scanning is not possible blindly. Most mobile stations are battery powered and have power limitations. A rapid scan rate for the set of networks depletes the battery.
In the present invention sleep time interval estimation can be made by the previous history of the network information available at the mobile station.
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SUMMARY OF THE INVENTION
Cellular telephone systems divide a geographical region into adjoining sections called Public Land Mobile Networks (PLMNs). The boundaries of the sections are often determined by size, geographical features, population density, or national borders. The region of every PLMN is further subdivided into cells. Cells can be visualized as small, overlapping, geographical zones covering the region. These zones, or cells, are joined to completely blanket the PLMN. Each cell has an allocation of distinct frequencies for communications with the mobile station. The frequencies of adjoining cells are different to prevent radio interference between mobile station users in adjoining cells.
Mobile stations are usually handheld telephones used by pedestrians or by individuals traveling in automobiles. The user of a mobile station contacts another user through communications with the cell. A mobile station is free to roam. That is, the mobile station is allowed to operate as it travels through a variety of geographical regions in the telephone system. To insure adequate communications, therefore, the mobile station will change cells, communicating with proximate cells as it moves. Based on the rate of change of PLMN, Location area and Cell identity parameters, user movement can be estimated that can be used to decide the sleep time interval. Battery level can also be considered as factor to decide sleep time interval.
Sleep time interval can be optimized very efficiently depending on the collected
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network (PLMN, Location area and Cell identity) and mobile information (Battery level).
Accordingly, this invention explains a method for conserving battery power in a mobile station during emergency service comprising the steps of:
(a) storing the location area identity information elements Cell Identity, Location Area code and PLMN information;
(b) comparing the Location area identity information elements with the previously stored identity information elements; and
(c ) estimating the time of background scanning based on the rate of change of said location area identity information elements, number of attempts and time period took to change from one information element to another.
Estimating the time of background scanning when there is a change in PLMN involves storing all information elements with time stamp and compared with the previous stored information elements. Based on the rate of change of PLMN and number of attempts took to change from one PLMN to another, background scanning time interval is calculated. If there is no change in PLMN, location area code is checked for any change and if there is change in said location area code, all information of location area code is stored with time stamp and compared with the previous stored location area code information. Based on the rate of change of location area code within the current time and number of attempts took to change from one location area code to another, background scanning time interval is calculated.
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Accordingly, this invention further explains a method for conserving battery power in a mobile station on no service period comprising the steps of:
(a) calculating the initial time for which mobile is in no service;
(b) incrementing the number of a no service counts on each scan;
(c) incrementing a secondary no service count if number of no service counts are greater than initial no service count; and
(d) calculating the sleep time interval based on the number of secondary no service count.
If number of service counts are less than the said initial no service count, sleep time interval is calculated based on the initial no service time period.
These and other objects, features and advantages of the present invention will become more apparent from the ensuing detailed description of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The drawings schematically show battery saving in a mobile station according to an embodiment of the present invention.
Figure 1 depicts estimation of sleep time interval when there is change in location area code.
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Figure 2 depicts estimation of sleep time interval when there is change in cell identity.
Figure 3 depicts estimation of sleep time interval when mobile is in no service area. DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. The following description and drawings are not to be construed as limiting the invention and numerous specific details are described to provide a thorough understanding of the present invention, as the basis for the claims and as a basis for teaching one skilled in the art how to make and/or use the invention. However in certain instances, well-known or conventional details are not described in order not to unnecessarily obscure the present invention in detail.
In the present invention sleep time interval is optimized very efficiently depending on the collected network (PLMN, Location area and Cell identity) and mobile information (Battery level). Following procedures are adapted based on service status of the mobile station.
Service Status: EMERGENCY SERVICE
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When UE goes in emergency service, it stores the Cell Identity (Cl), Location Area (LA) and PLMN information and compares the Location area Identity information (PLMN + LAC + Cl) with the previously stored information elements. Based on the rate of change of PLMN/LAC/CI, number of attempts and time period took to change from one PLMN/LAC/CI to another, time for the background scanning is estimated. Detail descriptions of the above procedure are given above in Fig. 1 and Fig. 2.
Over the period of time intervals these observations are made that will depicts the movement of mobile station.
• If the LA is changed w.r.t previous attempt, it is understood that UE is moving away from the city limit. (May be going in train, bus or a car).
• If the LA is not changed w.r.t previous attempt, it means UE is moving within a city limit.
• If the Cl is not changed w.r.t previous attempt, it means UE is idle at that place.
• If the Cl is changed in the same LA, it is under stood that UE is moving within a limited area (city).
Figure 1 is the flow chart diagram of the method of the present invention for estimation of sleep time interval when there is change in location area code. As in Fig. 1, based on PLMN information received by mobile station, back ground scan (BGS) is estimated. When PLMN is changed, it stores all information (PLMN/LAC/Cell) with time stamp and compared with the previous stored
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information. Based on the rate of change of PLMN and number of attempts took to change from one PLMN to another, BGS time interval is decided (Sleep time interval will be reduced when rate of change of PLMN is high). When there is no change in PLMN, location area code is checked and if there is change in location area code, it stores all information of LAC with time stamp and compared with the previous stored LAC information. Based on the rate of change of LAC within the current time and number of attempts took to change from one LAC to another, BGS time interval is decided.
Figure 2 is the flow chart diagram of the method of the present invention for estimation of sleep time interval when there is change in cell identity. As can be seen in Fig. 1, when there is no change in LAC, change in cell identity is being checked. In Fig. 2, when there is change in cell identity, sleep time interval is calculated based on the number of attempts and estimated time took to change from one cell to another When there is no change in cell identity, idle cell period (period for which there is no change in cell) is being checked. Based on the number of primary, secondary attempts and cell idle time, sleep time interval is recalculated.
Service Status: No SERVICE
When UE goes to no service area, it stores the first time stamp and on each scan time stamp is compared with previous time stamp. Based on the time stamp period and number of scan attempts, scanning time interval is estimated. Following are the two main criteria to estimate sleep time interval.
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• Observe how long UE is in No service.
• Depending on the duration by which UE is in No Service estimation is
made to keep the sleep time for the UE.
Detail descriptions of the above procedure are given above in Fig. 3.
Before making the estimate of scanning time interval, Battery level is also checked to make efficient estimate for the scanning. Following three range of Battery levels (Assuming 5 levels of battery indication) are decided to estimate sleep time interval
1. Full Battery (level 4 and 5): This range will not affect the scanning time interval estimated in Fig. 1, Fig. 2 and Fig. 3.
2. Average Battery (level 3): This will increase the scanning time interval estimated in Fig. 1, Fig. 2 and Fig. 3 by 25%.
3. Low Battery (level 1 and 2): This range will increase the scanning time interval estimated n Fig. 1, Fig. 2 and Fig. 3 by 50%.
Figure 3 is the flow chart diagram of the method of the present invention for estimation of sleep time interval when mobile is in no service area. As in Fig. 3, initial time is calculated for which mobile is in no service and on each scan, number of no service counts are increased. If number of no service counts are greater than initial no service count, it increments the secondary no service count and based on the number of secondary no service count, UE increase or decrease the sleep time interval. If number of service counts are less than initial no service count, sleep time interval is increased or decreased based on the initial no service time period.
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ADVANTAGES
In order to save battery power, the present invention provides the optimize sleep time interval based on previous stored network and mobile information during emergency or no service.
It will also be obvious to those skilled in the art that other control methods and apparatuses can be derived from the combinations of the various methods and apparatuses of the present invention as taught by the description and the accompanying drawings and these shall also be considered within the scope of the present invention. Further, description of such combinations and variations is therefore omitted above. It should also be noted that the host for storing the applications include but not limited to a microchip, microprocessor, handheld communication device, computer, rendering device or a multi function device.
Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom,
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GLOSSARY OF TERMS AND DEFINITIONS THEREOF
CI- Cell Identity
LA- Location Area
LAC- Location Area Code
PLMN - Public Land Mobile Network
UE- User Equipment
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Documents:

318-CHE-2005 FORM-5 27-11-2012.pdf

318-CHE-2006 AMENDED PAGES OF SPECIFICATION 27-11-2012.pdf

318-CHE-2006 AMENDED CLAIMS 27-11-2012.pdf

318-CHE-2006 CORRESPONDENCE OTHERS 08-02-2013.pdf

318-CHE-2006 OTHER PATENT DOCUMENT 08-02-2013.pdf

318-CHE-2006 POWER OF ATTORNEY 27-11-2012.pdf

318-CHE-2006 POWER OF ATTORNEY 08-02-2013.pdf

318-CHE-2006 CORRESPONDENCE OTHERS.pdf

318-CHE-2006 EXAMINATION REPORT REPLY RECEIVED 27-11-2012.pdf

318-CHE-2006 FORM-18.pdf

318-che-2006- claim.pdf

318-che-2006-abstract.pdf

318-che-2006-description(complete).pdf

318-che-correspo9ndence- others.pdf

318-che-drawings.pdf

318-che-form 1.pdf


Patent Number 255351
Indian Patent Application Number 318/CHE/2006
PG Journal Number 07/2013
Publication Date 15-Feb-2013
Grant Date 13-Feb-2013
Date of Filing 24-Feb-2006
Name of Patentee SAMSUNG INDIA SOFTWARE OPERATIONS PRIVATE LIMITED
Applicant Address BAGMANE LAKEVIEW, BLOCK 'B', NO. 66/1 BAGMANE TECH PARK, CV RAMAN NAGAR, BYRASANDRA BANGALORE-560093, KARNATAKA, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 HARI NARAYAN EMPLOYED AT SAMSUNG INDIA SOFTWARE OPERATIONS PVT. LTD., HAVING ITS OFFICE AT, BAGMANE LAKEVIEW, BLOCK 'B', NO. 66/1 BAGMANE TECH PARK, CV RAMAN NAGAR, BYRASANDRA BANGALORE-560093, KARNATAKA, INDIA
PCT International Classification Number H04M 1/73
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA