Title of Invention	A METHOD FOR GLOBAL POSITIONING SYSTEM (GPS) BASED NETWORK SELECTION DURING SERVICE ORIGINATION IN MULTI-RADIO ACCESS TECHNOLOGY (RAT) ENVIRONMENT
Abstract	The present invention, in general, relates to wireless communication, cellular communication and GPS. More particularly, this invention relates to a criterion for GPS based network selection during service origination in Multi -RAT deployment scenario. The invention explains a method for GPS based network selection during service origination in multi- RAT environment comprising the steps of: searching for system as per system selection table and camping on preferred system by MS when MS is powered ON; getting all overhead messages from the network and registering with the network by MS; doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS; camping on to the preferred system autonomously by MS when MS finds the said preferred system; sending a coverage profile message to the network where MS is currently camped on if MS originates a call; checking all the available RATs at the current location by the network; sending message to MS indicating the availability of all the RATS at current location by the network; selecting and tuning to a new preferred RAT and start getting service from the said RAT by MS; and servicing the said MS with the requested service by the network.

Title of Invention

A METHOD FOR GLOBAL POSITIONING SYSTEM (GPS) BASED NETWORK SELECTION DURING SERVICE ORIGINATION IN MULTI-RADIO ACCESS TECHNOLOGY (RAT) ENVIRONMENT

Abstract

The present invention, in general, relates to wireless communication, cellular communication and GPS. More particularly, this invention relates to a criterion for GPS based network selection during service origination in Multi -RAT deployment scenario. The invention explains a method for GPS based network selection during service origination in multi- RAT environment comprising the steps of: searching for system as per system selection table and camping on preferred system by MS when MS is powered ON; getting all overhead messages from the network and registering with the network by MS; doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS; camping on to the preferred system autonomously by MS when MS finds the said preferred system; sending a coverage profile message to the network where MS is currently camped on if MS originates a call; checking all the available RATs at the current location by the network; sending message to MS indicating the availability of all the RATS at current location by the network; selecting and tuning to a new preferred RAT and start getting service from the said RAT by MS; and servicing the said MS with the requested service by the network.

Full Text	FIELD OF INVENTION The present invention, in general, relates to wireless communication, cellular communication and GPS. More particularly, this invention relates to a criterion for GPS based network selection during service origination in Multi -RAT deployment scenario. DESCRIPTION OF RELATED ART In cellular systems, a wider region is divided into cells and each cell is covered by a BTS. Typically an operator would have deployed one RAT in all these cells. A typical single RAT deployment can be as shown in Figure 1. When MS is powered on, MS measures the signal strength of various frequencies or codes of the deployed RAT and camp on to it. Then MS receives all system information by listening to overhead messages from NW. Also MS registers with the NW by sending registration message. Now MS is ready to receive or originate calls to exchange user traffic. When MS wants to originate a call, it will send an Origination message to NW and NW will assign appropriate resources to MS. Then MS and NW will do service negotiation and start exchanging user traffic. Currently there are many RATs existing and are widely deployed by various operators and in various countries. Also many new RATs are being developed and standardized. These new RATs have various extra capabilities (in terms of more capacity, higher data rates, optimized for various services, better QoS, etc). With the availability of new RATs, operators have various choices and are willing to deploy the new RATs to capitalize on various advantages/features of the newly developed RATs. To deploy new RATs, operators have various choices: 1. Deploy the new RAT in the entire region of their operation at once and phase out the old RAT A. This option is very costly and existing user's MSs will be unusable. 2. Phase wise deployment of new RAT in selective regions depending on the demands for the new capabilities and services. A. This is done by overlaying the new RAT on the existing RAT. This choice is preferable as it has many advantages (like less initial cost, on-demand basis, less risky). As time goes, there will be so many RATs available with various capabilities and optimized for various services. Depending on the operator's needs (mainly driven by user's requirements) and constraints, operator can go for various RAT deployment scenarios. One of the typical deployment scenarios can be as shown in Figure 2. (a) OPERATION OF RELATED ART With reference to multi-RAT deployment scenario given in Figure 2, multiple RATs are deployed in the given region with following typical characteristics: 1. Various regions are covered by various RATs 2. No region has the coverage of all RATs which are shown in Figure 2 Also it should be noted that various RATs have various capabilities and have been optimized for various services. That is to say, no one RAT is good enough to provide best QoS for all the service that MS supports or wants to use. In this multi-RAT scenario, when MS is powered-on, it would have searched for all the RATs that it is capable of in a pre-defined order (i.e. prioritized and kept in MS's system selection table) and would have camped onto one of the preferred RATs available. When in IDLE state, MS keeps searching for various RATs that MS is capable of and are supposed to be available in the region and keep doing autonomous handoffs to the preferred RATs (as pre-defined in MS system selection table). This way, MS can always camp onto the preferred RAT that is available in that region. When MS wants to originate a service, it will simply send an origination message to NW that MS is currently camped on. Then in a multi-RAT scenario, how will NW provide the service that MS has requested for with the best QoS that the service needs? Simple approach In a simple scenario, the current NW can simply provide the requested service. Since MS is always camped onto the preferred system as per it's system selection table, this NW will be able to meet the QoS requirements of many of the applications that the MS supports. Also the order of systems (i.e. RATs) in the system selection table can be such that the systems on top of the table will be able to support most of the applications at better QoS. But, there will still a problem with this approach as the currently camped on NW may be the preferred system in terms of system selection table and also may be the best system in terms of giving good QoS for many applications that MS supports. But the preferred system (that MS currently camped on) may not be the best system (w.r.t. QoS requirements of a service) for all the applications that MS supports. In this simple art, when MS requests for a service to the currently camped on NW, the requested NW is simply providing the service even though it may not be the best RAT (out of currently available RATs to MS) in terms of meeting the QoS requirements of the requested service. Possible Alternative Approach In an alternate approach, MS can maintain a table which can contain a list of RATs (in reducing order of preference) for every application supported by it. NW provides information of availability of different RATs near MS location. MS selects and camp on to best system available in the region based on the table. In this case, the following issues can arise: 1. How will MS get the best QoS for the requested service (i.e. how will the best RAT be selected)? 2. How will NW know what all RATs are deployed in the region? 3. How will NW know RATs covered at current MS location? 4. How will NW know current MS position location precisely? Step(s) of Related Art Figure 3 shows the simple procedure for MS getting the service from a RAT NW in multi-RAT deployment scenario. The following describes the sequence of steps: 1. When MS is powered on, it searches for the system as per the order given in system selection table. 2. Once MS acquires a system, it gets all the overhead messages from the NW and MS registers itself with NW. 3. When MS in IDLE state, it can keep searching for a preferred system (as given in system selection table) by doing inter-RAT measurements. 4. If MS finds a preferred system, it can autonomously camp onto the preferred system. 5. If MS wants to get a service, MS sends an origination message to NW 6. NW services the MS for this requested application. 7. Once data exchange is over, call will be released 8. After call release, MS can again search for a preferred system and the above steps will be repeated, LIMITATIONS OF RELATED ART 1. MS not getting the best QoS for the requested service. 2. No effective utilization of capabilities of RATs, which are deployed in the region. 3. Quickly moving out of the current RAT (and triggering for handoff) i. As this best system may not have good coverage 4. No utilization of MS location information i. In near future, all MSs will have position location capability SUMMMARY OF THE INVENTION In a multi-RAT deployment scenario, where multiple RATs are covering various regions, MS needs to get the service from the best RAT always. This is applicable even at the time of service origination also. When MS is requesting for a service, MS needs to get the service from the best RAT (i.e. the RAT which can give best QoS for the requested service) out of available RAT at the current MS location. The RAT that MS is currently camped on may be the preferred RAT in terms of MS's system selection table but may not be the best RAT in terms of providing the QoS for the requested service. When MS requests for a service to the NW that it is currently camped on, NW will find out all the RATs available at the current MS location, and send this information to the MS. MS will maintain a table, which indicates the order of preference of the RATs for all the services supported by MS. Based on requested service and available RATs at the current location, MS can select the best RAT for the requested service. This selection of best RAT is based on parameters like requested service, MS capability (in terms of RATs it supports), MS current location, RAT coverage profile, etc. MS can inform its position location co-ordinates at the time of requesting for a service. Accordingly this invention explains a method for GPS based network selection during service origination in multi- RAT environment comprising the steps of: (a) searching for system as per system selection table and camping on preferred system by MS when MS is powered ON; (b) getting all overhead messages from the network and registering with the network by MS; (c) doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS; (d) camping on to the preferred system autonomously by MS when MS finds the said preferred system; (e) sending a coverage profile message to the network where MS is currently camped on if MS originates a call; (f) checking all the available RATs at the current location by the network; (g) sending message to MS indicating the availability of all the RATS at current location by the network; (h) selecting and tuning to a new preferred RAT and start getting service from the said RAT by MS; and (i) servicing the said MS with the requested service by the network. For selecting the new preferred RAT for a service, MS uses the following information: (1) the QoS requirements of the said service MS has requested for; (2) RAT coverage profile at the place where MS is currently located; (3) MS position location co-ordinates; (4) MS capability; (5) application and RAT preference order table; and (6) Signal strength of best RAT as seen at MS. The said RAT coverage profile is stored in location server and is queried from MSCs where the said location server is the one, which has location specific information. The RAT coverage profile of the region is determined by extensive RF measurements and drive tests and stores the said information in a database in the Location server. MS sends the current position location co-ordinates in Origination message after determine its position location co-ordinates precisely. Different modes and bands supported by MS are indicated by MS capability. Application and RAT preference order table is a table which MS maintains and consisting of different applications supported by MS and the corresponding order of preference of RATs. MS checks the signal strength of the selected RAT, and if signal strength is not adequate then MS selects a RAT which is available at current location and is given in the table. 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 ACCOMPANYING DRAWINGS Figure 1 illustrates typical deployment of NW with single RAT in a given region. Figure 2 illustrates typical deployment of NW with multiple RATs in a given region. Figure 3 is a flow chart for MS getting service from NW in prior art. Figure 4 is a flow chart for MS getting service (for an application) from NW in preferred embodiment. Figure 5 illustrates message sequence chart for MS getting service (for an application) from NW in preferred embodiment. Points to be considered while seeing the drawings: 1. The diagrams and message sequences are shown just for illustrating the example scenario/sequence and need not be the actual set of messages that are exchanged 2. The description or identification of fields in each message is not critical for illustrating the idea. But, the description of the message is understood when one goes through the steps of the related art. 3. Timers and other negative scenarios are not captured in the diagrams as these are not critical for illustrating the idea Alternatives: Message sequence can be altered. Message names as shown in MSC can be changed. Some more messages can be added or some messages can be removed with reference to messages shown in MSC (FIGURE 5). 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 view of the above issues and limitations of the prior art, we propose a new criterion for a network selection during service origination in a multi-RAT deployment scenario that is shown in Figure 2. In a multi-RAT deployment scenario, various RATs are deployed in various regions. These RATs are deployed such that some combination of RATs is covering one region and another combination of RATs is covering another region. A typical deployment scenario is shown in Figure 2. Figure 3 is a flow chart for MS getting service from NW in prior art. 1.Start procedure. 2.MS is powered ON. 3.MS searches for system as per system selection table and camp on preferred system. 4.MS gets all overhead messages from the network and registers itself with the network. 5.MS keeps doing inter-RAT measurements in idle state to look for preferred system as per system selection table. 6.Whenever MS finds a preferred system, MS camps on to it autonomously. 7.A check is made to confirm whether MS wants to originate call. 8. If MS wants to originate call an origination message is send to the network that MS is currently camped on. 9.Network serves the MS for this particular application. 10-After finishing the call, call release happens. 11.End of procedure. Figure 4 is a flow chart for MS getting service (for an application) from NW in the preferred embodiment. 1.Start procedure. 2.MS is powered ON. 3.MS searches for system as per system selection table and camp on preferred system. 4.MS gets all overhead messages from the network and registers itself with the network. 5.MS keeps doing inter-RAT measurements in idle state to look for preferred system as per system selection table. 6.Whenever MS finds a preferred system, MS camps on to it autonomously. 7.A check is made to confirm whether MS wants to originate call. 8. If MS wants to originate call a coverage profile request message is send to the network that MS is currently camped on. 9. Network checking all the available RATs at the current location. 10.Network sending message to MS indicating the availability of all the RATS at current location. 11 .MS selects and tunes to new RAT and start getting service from it. 12.Network serves the MS from this application. 13.After finishing the call the call is released. 14.End the procedure. Figure 5 illustrates message sequence chart for MS getting service (for an application) from NW in preferred embodiment. When MS wants to originate a service, MS sends a network coverage profile request message to the currently camped on NW. In this message, MS sends its position location co-ordinates and the service it is requesting. Upon receiving the message, NW checks, if there is any other RAT covering the current MS location. NW compiles a network coverage profile response message, which contains the information of all the RATs present at the MS current location and sends it to MS. MS selects the best RAT for the requested service based on the received message table. MS send origination message to the selected RAT. In this approach, for selecting the best RAT for the service, MS uses the following information: 1. The service that MS is requesting for and hence the QoS requirements of this service 2. RAT coverage profile at the place where MS is currently located 3. MS position location co-ordinates 4. MS capability 5. Application and RAT preference order table 6. Optionally, signal strength of best RAT as seen at MS Service information: MS sends the service information in Origination message. NW can easily derive the QoS requirements of a service by knowing the service. RAT coverage profile: RAT coverage profile is stored in Location server and can be queried from MSCs. Location server is the one, which has location specific information. We will determine the RAT coverage profile of the region by extensive RF measurements and drive tests and store that database in the Location server. RAT coverage profile tells us about the coverage of various RAT at various locations precisely. MS position location co-ordinates: MS sends it's current position location coordinates in Origination message. MS can determine it's position location coordinates precisely with the help of Global Positioning system or by some other methods. MS capability: Different Modes and band supported by MS. Application and RAT preference order table: MS maintains a table which consists of different applications supported by MS and the corresponding order of Signal strength of the best RAT: MS checks the signal strength of the selected RAT, if signal strength is not adequate then MS can select a RAT which is available at current location and given in the table. Operation In Figure 2, four position locations are shown where MS could be positioning at different times at the time of service origination. When MS is requesting for a service (let's us assume this is "high speed internet browsing" application), let us consider FOUR positions and see what happens when MS originates for a service at those position locations. Here we assume that MS has camped on to the preferred RAT as per it's system selection table. The order/priority of systems in system selection table is assumed to be: UMTS, GSM, CDMA2000 and Wi-Fi. Also to provide high speed internet browsing service, it is assumed that the order of preference as: Wi-Fi, UMTS, CDMA2000 and GSM. Location-1: This position location is covered by only ONE RAT (CDMA2000). MS would have camped onto CDMA2000 system. So CDMA2000 RAT will provide the service upon MS request. Location-2: This position location is covered by TWO RATs (CDMA2000 + GSM). MS would have camped onto GSM. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about CDMA2000 and GSM NW. MS will select CDMA2000 based on the table given above and gets the service from CDMA2000 system. Location-3: This position location is covered by TWO RATs (CDMA2000 + UMTS). MS would have camped onto UMTS. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about UMTS and CDMA2000. MS will select UMTS based on the table given above and gets the service from UMTS system. Location-4: This position location is covered by THREE RATs (CDMA2000 + UMTS + Wi-Fi). MS would have camped onto UMTS. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about Wi-Fi, UMTS, and CDMA2000 NW. MS will select Wi-Fi based on the table given above and gets the service from Wi-Fi system. Assumptions: 1. MS is multimode A. MS supports Multiple RATs and their frequencies 2. MS has position location capability A. Like GPS functionality 3. NW has enough information on which region is covered by what all RATs/NWs A. This RAT coverage profile can be determined with the help of various measurements and database is maintained at network side 4. No one RAT is capable of giving the best QoS for all the applications that MS supports A. i.e. various RATs are optimized for various services B. For ex: CDMA20001 x is not the best RAT for Video streaming ADVANTAGES 1. Better QoS for the chosen service A. As we are always getting the service from the best RAT deployed in that region 2. Efficient utilization of various RATs unique capabilities/advantages A. Hence better NW resource utilization B. Hence enhanced capacity C. Hence enhanced Revenue for operators 3. Quicker best system selection at the time of service origination A. For a chosen service B. No need for complex and time consuming inter-RAT measures at MS to select best system for the chose service 4. Finer granularity in knowing MS location for NW to take better decision on RAT coverage A. Earlier methods have granularity of only at the level of cell/sector or location area. 5. Efficient utilization of MS position location information EFFECTS More time for establishing a service when system other than current serving system is selected as best system for the required 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. GLOSSARY OF TERMS AND DEFINITIONS THEREOF BS/BTS: Base station, which is responsible for air-interface connection with MS Better/Best RAT: A RAT other than serving RAT which can service the current MS application better in terms of meeting quality of service requirements, better data rate etc CDMA: Code Division Multiple Access Connected state: MS is in this state when there is a connection (for user data exchange) established with NW GPS: Global positioning system GSM : Global System for Mobile communication IDLE state: MS is in this state when there is no connection (for user data exchange) established with NW Location server: The server in which we maintain RAT coverage profile and various other location related information MS: Mobile station NW: Network, which consists of BS and MSC. This term is used to refer to the serving NW/RAT (i.e. the NW that MS is currently camped on) in general unless otherwise specified Preferred RAT: A RAT, which is preferable for MS to camp on in its IDLE state. This preference is given in system selection table Position location co-ordinates: The precise current location of MS (This can be estimated with the help of "Global Position System") QOS: Quality of Service. Some parameters for measuring this could be: data rate, delay, frame error rate, etc RAT: Radio Access Technology. Examples: CDMA2000, GSM, UMTS, 4G etc RAT coverage profile: The coverage profile of various RATs at various locations in that region. This can be estimated / determined with the help of extensive RF measurements and drive tests Region: Entire region in which the mobile NW is deployed Service/Application: The application that mobile wants to use. Example: Voice call, High speed internet browsing, Video telephony or Video streaming, etc. WE CLAIM 1. A method for GPS based network selection during service origination in multi- RAT environment comprising the steps of: (a) searching for system as per system selection table and camping on preferred system by MS when MS is powered ON; (b) getting all overhead messages from the network and registering with the network by MS; (c) doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS; (d) camping on to the preferred system autonomously by MS when MS finds the said preferred system; (e) sending a coverage profile message to the network where MS is currently camped on if MS originates a call; (f) checking all the available RATs at the current location by the network; (g) sending message to MS indicating the availability of all the RATS at current location by the network; (h) selecting and tuning to a new preferred RAT and start getting service from the said RAT by MS; and (i) servicing the said MS with the requested service by the network. 2. A method as claimed in claim 1 wherein for selecting the new preferred RAT for a service, MS uses the information: (i) the QoS requirements of the said service MS has requested for; (ii) RAT coverage profile at the place where MS is currently located; (iii)MS position location co-ordinates; (iv)MS capability; (v) application and RAT preference order table; and (vi) signal strength of best RAT as seen at MS. 3. A method as claimed in claim 2 wherein MS sends the service information in origination message and the network derives the QoS requirements of a service by knowing the said service information. 4. A method as claimed in claim 2 wherein the said RAT coverage profile is stored in location server and is queried from MSCs where the said location server is the one, which has location specific information. 5. A method as claimed in claim 2 wherein the RAT coverage profile of the region is determined by extensive RF measurements and drive tests and stores the said information in a database in the Location server. 6. A method as claimed in claim 2 wherein MS sends the current position location co-ordinates in Origination message after determining its position location coordinates precisely. 7. A method as claimed in claim 2 wherein different modes and bands supported by MS is indicated by MS capability. 8. A method as claimed in claim 2 wherein application and RAT preference order table is a table which MS maintains and consisting of different applications supported by MS and the corresponding order of preference of RATs. 9. A method as claimed in claim 2 wherein MS checks the signal strength of the selected RAT, and if signal strength is not adequate then MS selects a RAT which is available at current location and is given in the table. 10. A method for GPS based network selection during service origination in multi- RAT environment such as herein described and illustrated particularly with reference to the accompanying drawings.

Full Text

FIELD OF INVENTION
The present invention, in general, relates to wireless communication, cellular communication and GPS. More particularly, this invention relates to a criterion for GPS based network selection during service origination in Multi -RAT deployment scenario.
DESCRIPTION OF RELATED ART
In cellular systems, a wider region is divided into cells and each cell is covered by a BTS. Typically an operator would have deployed one RAT in all these cells. A typical single RAT deployment can be as shown in Figure 1.
When MS is powered on, MS measures the signal strength of various frequencies or codes of the deployed RAT and camp on to it. Then MS receives all system information by listening to overhead messages from NW. Also MS registers with the NW by sending registration message. Now MS is ready to receive or originate calls to exchange user traffic.
When MS wants to originate a call, it will send an Origination message to NW and NW will assign appropriate resources to MS. Then MS and NW will do service negotiation and start exchanging user traffic.
Currently there are many RATs existing and are widely deployed by various operators and in various countries. Also many new RATs are being developed and standardized. These new RATs have various extra capabilities (in terms of more capacity, higher data rates, optimized for various services, better QoS, etc). With the availability of new RATs, operators have various choices and are willing to deploy the new RATs to capitalize on various advantages/features of the newly developed RATs.
To deploy new RATs, operators have various choices:

1. Deploy the new RAT in the entire region of their operation at once and
phase out the old RAT
A. This option is very costly and existing user's MSs will be unusable.
2. Phase wise deployment of new RAT in selective regions depending on the
demands for the new capabilities and services.
A. This is done by overlaying the new RAT on the existing RAT. This choice is preferable as it has many advantages (like less initial cost, on-demand basis, less risky).
As time goes, there will be so many RATs available with various capabilities and optimized for various services. Depending on the operator's needs (mainly driven by user's requirements) and constraints, operator can go for various RAT deployment scenarios. One of the typical deployment scenarios can be as shown in Figure 2.
(a) OPERATION OF RELATED ART
With reference to multi-RAT deployment scenario given in Figure 2, multiple RATs are deployed in the given region with following typical characteristics:
1. Various regions are covered by various RATs
2. No region has the coverage of all RATs which are shown in Figure 2
Also it should be noted that various RATs have various capabilities and have been optimized for various services. That is to say, no one RAT is good enough to provide best QoS for all the service that MS supports or wants to use.
In this multi-RAT scenario, when MS is powered-on, it would have searched for all the RATs that it is capable of in a pre-defined order (i.e. prioritized and kept in MS's system selection table) and would have camped onto one of the preferred RATs available.

When in IDLE state, MS keeps searching for various RATs that MS is capable of and are supposed to be available in the region and keep doing autonomous handoffs to the preferred RATs (as pre-defined in MS system selection table). This way, MS can always camp onto the preferred RAT that is available in that region.
When MS wants to originate a service, it will simply send an origination message to NW that MS is currently camped on.
Then in a multi-RAT scenario, how will NW provide the service that MS has requested for with the best QoS that the service needs?
Simple approach
In a simple scenario, the current NW can simply provide the requested service. Since MS is always camped onto the preferred system as per it's system selection table, this NW will be able to meet the QoS requirements of many of the applications that the MS supports. Also the order of systems (i.e. RATs) in the system selection table can be such that the systems on top of the table will be able to support most of the applications at better QoS.
But, there will still a problem with this approach as the currently camped on NW may be the preferred system in terms of system selection table and also may be the best system in terms of giving good QoS for many applications that MS supports. But the preferred system (that MS currently camped on) may not be the best system (w.r.t. QoS requirements of a service) for all the applications that MS supports.
In this simple art, when MS requests for a service to the currently camped on NW, the requested NW is simply providing the service even though it may not be the best RAT (out of currently available RATs to MS) in terms of meeting the QoS

requirements of the requested service.
Possible Alternative Approach
In an alternate approach, MS can maintain a table which can contain a list of RATs (in reducing order of preference) for every application supported by it. NW provides information of availability of different RATs near MS location. MS selects and camp on to best system available in the region based on the table. In this case, the following issues can arise:
1. How will MS get the best QoS for the requested service (i.e. how will the best RAT be selected)?
2. How will NW know what all RATs are deployed in the region?
3. How will NW know RATs covered at current MS location?
4. How will NW know current MS position location precisely?
Step(s) of Related Art
Figure 3 shows the simple procedure for MS getting the service from a RAT NW in multi-RAT deployment scenario. The following describes the sequence of steps:
1. When MS is powered on, it searches for the system as per the order given in system selection table.
2. Once MS acquires a system, it gets all the overhead messages from the NW and MS registers itself with NW.
3. When MS in IDLE state, it can keep searching for a preferred system (as given in system selection table) by doing inter-RAT measurements.
4. If MS finds a preferred system, it can autonomously camp onto the preferred system.
5. If MS wants to get a service, MS sends an origination message to NW
6. NW services the MS for this requested application.
7. Once data exchange is over, call will be released

8. After call release, MS can again search for a preferred system and the above steps will be repeated,
LIMITATIONS OF RELATED ART
1. MS not getting the best QoS for the requested service.
2. No effective utilization of capabilities of RATs, which are deployed in the region.
3. Quickly moving out of the current RAT (and triggering for handoff)
i. As this best system may not have good coverage
4. No utilization of MS location information
i. In near future, all MSs will have position location capability
SUMMMARY OF THE INVENTION
In a multi-RAT deployment scenario, where multiple RATs are covering various regions, MS needs to get the service from the best RAT always. This is applicable even at the time of service origination also. When MS is requesting for a service, MS needs to get the service from the best RAT (i.e. the RAT which can give best QoS for the requested service) out of available RAT at the current MS location. The RAT that MS is currently camped on may be the preferred RAT in terms of MS's system selection table but may not be the best RAT in terms of providing the QoS for the requested service.
When MS requests for a service to the NW that it is currently camped on, NW will find out all the RATs available at the current MS location, and send this information to the MS. MS will maintain a table, which indicates the order of preference of the RATs for all the services supported by MS. Based on requested service and available RATs at the current location, MS can select the best RAT for

the requested service.
This selection of best RAT is based on parameters like requested service, MS capability (in terms of RATs it supports), MS current location, RAT coverage profile, etc. MS can inform its position location co-ordinates at the time of requesting for a service.
Accordingly this invention explains a method for GPS based network selection during service origination in multi- RAT environment comprising the steps of:
(a) searching for system as per system selection table and camping on preferred system by MS when MS is powered ON;
(b) getting all overhead messages from the network and registering with the network by MS;
(c) doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS;
(d) camping on to the preferred system autonomously by MS when MS finds the said preferred system;
(e) sending a coverage profile message to the network where MS is currently camped on if MS originates a call;
(f) checking all the available RATs at the current location by the network;
(g) sending message to MS indicating the availability of all the RATS at current location by the network;
(h) selecting and tuning to a new preferred RAT and start getting service from
the said RAT by MS; and (i) servicing the said MS with the requested service by the network.
For selecting the new preferred RAT for a service, MS uses the following information:
(1) the QoS requirements of the said service MS has requested for;
(2) RAT coverage profile at the place where MS is currently located;
(3) MS position location co-ordinates;
(4) MS capability;

(5) application and RAT preference order table; and
(6) Signal strength of best RAT as seen at MS.
The said RAT coverage profile is stored in location server and is queried from MSCs where the said location server is the one, which has location specific information. The RAT coverage profile of the region is determined by extensive RF measurements and drive tests and stores the said information in a database in the Location server. MS sends the current position location co-ordinates in Origination message after determine its position location co-ordinates precisely. Different modes and bands supported by MS are indicated by MS capability. Application and RAT preference order table is a table which MS maintains and consisting of different applications supported by MS and the corresponding order of preference of RATs. MS checks the signal strength of the selected RAT, and if signal strength is not adequate then MS selects a RAT which is available at current location and is given in the table.
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 ACCOMPANYING DRAWINGS
Figure 1 illustrates typical deployment of NW with single RAT in a given region.
Figure 2 illustrates typical deployment of NW with multiple RATs in a given region.
Figure 3 is a flow chart for MS getting service from NW in prior art.
Figure 4 is a flow chart for MS getting service (for an application) from NW in preferred embodiment.

Figure 5 illustrates message sequence chart for MS getting service (for an application) from NW in preferred embodiment.
Points to be considered while seeing the drawings:
1. The diagrams and message sequences are shown just for illustrating the example scenario/sequence and need not be the actual set of messages that are exchanged
2. The description or identification of fields in each message is not critical for illustrating the idea. But, the description of the message is understood when one goes through the steps of the related art.
3. Timers and other negative scenarios are not captured in the diagrams as these are not critical for illustrating the idea
Alternatives:
Message sequence can be altered.
Message names as shown in MSC can be changed.
Some more messages can be added or some messages can be removed with reference to messages shown in MSC (FIGURE 5).
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 view of the above issues and limitations of the prior art, we propose a new criterion for a network selection during service origination in a multi-RAT deployment scenario that is shown in Figure 2.
In a multi-RAT deployment scenario, various RATs are deployed in various regions. These RATs are deployed such that some combination of RATs is covering one region and another combination of RATs is covering another region. A typical deployment scenario is shown in Figure 2.
Figure 3 is a flow chart for MS getting service from NW in prior art.
1.Start procedure.
2.MS is powered ON.
3.MS searches for system as per system selection table and camp on preferred
system.
4.MS gets all overhead messages from the network and registers itself with the
network.
5.MS keeps doing inter-RAT measurements in idle state to look for preferred
system as per system selection table.
6.Whenever MS finds a preferred system, MS camps on to it autonomously.
7.A check is made to confirm whether MS wants to originate call.
8. If MS wants to originate call an origination message is send to the network that
MS is currently camped on.
9.Network serves the MS for this particular application.
10-After finishing the call, call release happens.
11.End of procedure.

Figure 4 is a flow chart for MS getting service (for an application) from NW in the preferred embodiment.
1.Start procedure.
2.MS is powered ON.
3.MS searches for system as per system selection table and camp on preferred
system.
4.MS gets all overhead messages from the network and registers itself with the
network.
5.MS keeps doing inter-RAT measurements in idle state to look for preferred
system as per system selection table.
6.Whenever MS finds a preferred system, MS camps on to it autonomously.
7.A check is made to confirm whether MS wants to originate call.
8. If MS wants to originate call a coverage profile request message is send to the network that MS is currently camped on.
9. Network checking all the available RATs at the current location.
10.Network sending message to MS indicating the availability of all the RATS at
current location.
11 .MS selects and tunes to new RAT and start getting service from it.
12.Network serves the MS from this application.
13.After finishing the call the call is released.
14.End the procedure.
Figure 5 illustrates message sequence chart for MS getting service (for an application) from NW in preferred embodiment.
When MS wants to originate a service, MS sends a network coverage profile request message to the currently camped on NW. In this message, MS sends its position location co-ordinates and the service it is requesting. Upon receiving the message, NW checks, if there is any other RAT covering the current MS location. NW compiles a network coverage profile response message, which contains the

information of all the RATs present at the MS current location and sends it to MS. MS selects the best RAT for the requested service based on the received message table. MS send origination message to the selected RAT.
In this approach, for selecting the best RAT for the service, MS uses the following information:
1. The service that MS is requesting for and hence the QoS requirements of this service
2. RAT coverage profile at the place where MS is currently located
3. MS position location co-ordinates
4. MS capability
5. Application and RAT preference order table
6. Optionally, signal strength of best RAT as seen at MS
Service information: MS sends the service information in Origination message. NW can easily derive the QoS requirements of a service by knowing the service.
RAT coverage profile: RAT coverage profile is stored in Location server and can be queried from MSCs. Location server is the one, which has location specific information. We will determine the RAT coverage profile of the region by extensive RF measurements and drive tests and store that database in the Location server. RAT coverage profile tells us about the coverage of various RAT at various locations precisely.
MS position location co-ordinates: MS sends it's current position location coordinates in Origination message. MS can determine it's position location coordinates precisely with the help of Global Positioning system or by some other methods. MS capability: Different Modes and band supported by MS.
Application and RAT preference order table: MS maintains a table which consists of different applications supported by MS and the corresponding order of

Signal strength of the best RAT: MS checks the signal strength of the selected RAT, if signal strength is not adequate then MS can select a RAT which is available at current location and given in the table.
Operation
In Figure 2, four position locations are shown where MS could be positioning at different times at the time of service origination.
When MS is requesting for a service (let's us assume this is "high speed internet browsing" application), let us consider FOUR positions and see what happens when MS originates for a service at those position locations. Here we assume that MS has camped on to the preferred RAT as per it's system selection table. The order/priority of systems in system selection table is assumed to be: UMTS, GSM, CDMA2000 and Wi-Fi.
Also to provide high speed internet browsing service, it is assumed that the order of preference as: Wi-Fi, UMTS, CDMA2000 and GSM.

Location-1: This position location is covered by only ONE RAT (CDMA2000). MS would have camped onto CDMA2000 system. So CDMA2000 RAT will provide the service upon MS request.
Location-2: This position location is covered by TWO RATs (CDMA2000 + GSM). MS would have camped onto GSM. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about CDMA2000 and GSM NW. MS will select CDMA2000 based on the table given above and gets the service from CDMA2000 system.
Location-3: This position location is covered by TWO RATs (CDMA2000 + UMTS). MS would have camped onto UMTS. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about UMTS and CDMA2000. MS will select UMTS based on the table given above and gets the service from UMTS system.
Location-4: This position location is covered by THREE RATs (CDMA2000 + UMTS + Wi-Fi). MS would have camped onto UMTS. Upon seeing the service request from MS, NW checks the available RATs at current MS location send message to MS containing information about Wi-Fi, UMTS, and CDMA2000 NW. MS will select Wi-Fi based on the table given above and gets the service from Wi-Fi system.
Assumptions:
1. MS is multimode
A. MS supports Multiple RATs and their frequencies
2. MS has position location capability

A. Like GPS functionality
3. NW has enough information on which region is covered by what all
RATs/NWs
A. This RAT coverage profile can be determined with the help of various measurements and database is maintained at network side
4. No one RAT is capable of giving the best QoS for all the applications that
MS supports
A. i.e. various RATs are optimized for various services
B. For ex: CDMA20001 x is not the best RAT for Video streaming
ADVANTAGES
1. Better QoS for the chosen service
A. As we are always getting the service from the best RAT deployed in that region
2. Efficient utilization of various RATs unique capabilities/advantages
A. Hence better NW resource utilization
B. Hence enhanced capacity
C. Hence enhanced Revenue for operators
3. Quicker best system selection at the time of service origination
A. For a chosen service
B. No need for complex and time consuming inter-RAT measures at MS
to select best system for the chose service
4. Finer granularity in knowing MS location for NW to take better decision on
RAT coverage
A. Earlier methods have granularity of only at the level of cell/sector or location area.

5. Efficient utilization of MS position location information
EFFECTS
More time for establishing a service when system other than current serving system is selected as best system for the required 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.

GLOSSARY OF TERMS AND DEFINITIONS THEREOF
BS/BTS: Base station, which is responsible for air-interface connection with MS
Better/Best RAT: A RAT other than serving RAT which can service the current MS application better in terms of meeting quality of service requirements, better data rate etc
CDMA: Code Division Multiple Access
Connected state: MS is in this state when there is a connection (for user data exchange) established with NW
GPS: Global positioning system
GSM : Global System for Mobile communication
IDLE state: MS is in this state when there is no connection (for user data exchange) established with NW
Location server: The server in which we maintain RAT coverage profile and various other location related information
MS: Mobile station
NW: Network, which consists of BS and MSC. This term is used to refer to the serving NW/RAT (i.e. the NW that MS is currently camped on) in general unless otherwise specified
Preferred RAT: A RAT, which is preferable for MS to camp on in its IDLE state. This preference is given in system selection table

Position location co-ordinates: The precise current location of MS (This can be estimated with the help of "Global Position System")
QOS: Quality of Service. Some parameters for measuring this could be: data rate, delay, frame error rate, etc
RAT: Radio Access Technology. Examples: CDMA2000, GSM, UMTS, 4G etc
RAT coverage profile: The coverage profile of various RATs at various locations in that region. This can be estimated / determined with the help of extensive RF measurements and drive tests
Region: Entire region in which the mobile NW is deployed
Service/Application: The application that mobile wants to use. Example: Voice call, High speed internet browsing, Video telephony or Video streaming, etc.

WE CLAIM
1. A method for GPS based network selection during service origination in multi-
RAT environment comprising the steps of:
(a) searching for system as per system selection table and camping on preferred system by MS when MS is powered ON;
(b) getting all overhead messages from the network and registering with the network by MS;
(c) doing inter-RAT measurements in idle state to look for preferred system as per system selection table by MS;
(d) camping on to the preferred system autonomously by MS when MS finds the said preferred system;
(e) sending a coverage profile message to the network where MS is currently camped on if MS originates a call;
(f) checking all the available RATs at the current location by the network;
(g) sending message to MS indicating the availability of all the RATS at current location by the network;
(h) selecting and tuning to a new preferred RAT and start getting service from
the said RAT by MS; and (i) servicing the said MS with the requested service by the network.
2. A method as claimed in claim 1 wherein for selecting the new preferred RAT
for a service, MS uses the information:
(i) the QoS requirements of the said service MS has requested for;

(ii) RAT coverage profile at the place where MS is currently located;
(iii)MS position location co-ordinates;
(iv)MS capability;
(v) application and RAT preference order table; and
(vi) signal strength of best RAT as seen at MS.
3. A method as claimed in claim 2 wherein MS sends the service information in origination message and the network derives the QoS requirements of a service by knowing the said service information.
4. A method as claimed in claim 2 wherein the said RAT coverage profile is stored in location server and is queried from MSCs where the said location server is the one, which has location specific information.
5. A method as claimed in claim 2 wherein the RAT coverage profile of the region is determined by extensive RF measurements and drive tests and stores the said information in a database in the Location server.
6. A method as claimed in claim 2 wherein MS sends the current position location co-ordinates in Origination message after determining its position location coordinates precisely.
7. A method as claimed in claim 2 wherein different modes and bands supported by MS is indicated by MS capability.

8. A method as claimed in claim 2 wherein application and RAT preference order
table is a table which MS maintains and consisting of different applications
supported by MS and the corresponding order of preference of RATs.
9. A method as claimed in claim 2 wherein MS checks the signal strength of the
selected RAT, and if signal strength is not adequate then MS selects a RAT
which is available at current location and is given in the table.
10. A method for GPS based network selection during service origination in multi-
RAT environment such as herein described and illustrated particularly with
reference to the accompanying drawings.

Documents:

1955-CHE-2005 AMENDED PAGES OF SPECIFICATION 13-12-2012.pdf

1955-CHE-2005 AMENDED CLAIMS 13-12-2012.pdf

1955-CHE-2005 CORRESPONDENCE OTHERS 30-01-2013.pdf

1955-CHE-2005 EXAMINATION REPORT REPLY RECEIVED 13-12-2012.pdf

1955-CHE-2005 FORM-1 13-12-2012.pdf

1955-CHE-2005 FORM-1 30-01-2013.pdf

1955-CHE-2005 FORM-13 13-12-2012.pdf

1955-CHE-2005 FORM-5 13-12-2012.pdf

1955-CHE-2005 OTHER PATENT DOCUMENT 13-12-2012.pdf

1955-CHE-2005 POWER OF ATTORNEY 30-01-2013.pdf

1955-CHE-2005 FORM-13 19-06-2006.pdf

1955-che-2005-abstract.pdf

1955-che-2005-claims.pdf

1955-che-2005-correspondnece-others.pdf

1955-che-2005-description(complete).pdf

1955-che-2005-drawings.pdf

1955-che-2005-form 1.pdf

1955-che-2005-form 13.pdf

1955-che-2005-form 26.pdf

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Patent Number

255236

Indian Patent Application Number

1955/CHE/2005

PG Journal Number

06/2013

Publication Date

08-Feb-2013

Grant Date

06-Feb-2013

Date of Filing

29-Dec-2005

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-560 093.

Inventors:

#	Inventor's Name	Inventor's Address
1	SUDHIR KUMAR BAGHEL	EMPLOYED AT SAMSUNG ELECTRONICS CO.LTD., INDIA SOFTWARE OPERATIONS(SISO), HAVING ITS OFFICE AT, J.P. TECHNO PARK, 3/1, MILLERS ROAD, BANGLORE 560 052, KARANATAKA, INDIA
2	VADLAPUDI TSV PRASAD	EMPLOYED AT SAMSUNG ELECTRONICS CO.LTD., INDIA SOFTWARE OPERATIONS(SISO), HAVING ITS OFFICE AT, J.P. TECHNO PARK, 3/1, MILLERS ROAD, BANGLORE 560 052, KARANATAKA, INDIA

PCT International Classification Number

H04B7/185

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA