Title of Invention

A SYSTEM FOR CROSS PAGING IN A HYBRID ACCESS TERMINAL AND INTER RADIO ACCESS TECHNOLOGY DATA SESSION HANDOFF BETWEEN NETWORKS

Abstract

This invention provides an architecture for cross paging and inter-RAT data session handoff for amulti mode (hybrid) AT operating between HRPD and CDMA2000 1x networks, depending on the MS RAT capabilities, Ms location, Network ondition, RAT coverage profile etc. duitably analysed and interpreted by an inter working function (IWF). The cross paging and inter-RAT data session handoff between HRPD and CDMA2000 1X networkzs is possible in dormant as well as active session. In this communication system at knows about the rat deployment in its service area and mobile switching centre (MSC) knows the serving RAT and network details for the AT. This method proposes an inter-working solution (IWS) which has the intelligence to decipher the 1x pilot information for transating 1x message in CDMA2000 LAC formast and to interpret the interface with MSC viz. A1 interface MSC can talk to HRPD access network via IWs and can query update the netwoprk element (HLR) for serving RAT asnd network details for tje AT.

Full Text

FIELD OF TECHNOLOGY This invention in general relates to mobile communication techniques in networks such as CDMA and HRPD. Further, this invention relates to a novel architecture and system for allowing handoff flows on network level between HRPD (EVDO) and 1x networks on which a hybrid Access Terminal (AT) such as the Mobile terminal of CDMA2000 camps. More particularly, this invention relates to a system for cross paging and inter- rat data session handoff between HRPD and CDMA2000 1x networks. DESCRIPTION OF THE RELATED ART The advent of hybrid access terminal (HAT) has created a revolution in the field of telecommunication. Hybrid ATs can support a wide range of Radio Access Technologies (RAT) such as CDMA2000, GSM, UMTS, 4G etc. Present invention takes in to account of a hybrid AT that supports both HRPD and CDMA 20001x that are deployed widely in many parts of the world. HRPD (High Rate Packet Data network) is defined as per C.S0024 standard of 3GPP2 and CDMA 2000 1X network is defined as per C.S0002 to C.S0006 standards of 3GPP2. The advantages of HRPD are high data rate and the flexibility for customization to increase its efficiency to cater for data only. On the other hand 1x is mostly employed for voice services but supports data also. If the best features of both can be utilized in the deployed areas then a better service can be provided to the end users. For transparent and seamless movement for the end user, handoff between HRPD and 1x network is to be facilitated. This invention unveils architecture for facilitating handoff and cross paging between CDMA2000 and HRPD networks. The current hybrid AT supporting both 1x and HRPD standards functions with two independent stacks and no handoff is supported across the two. Therefore when the mobile station (MS) is tuned to HRPD network, it monitors the 1x control channel in both idle and connected states and looks for 1x pages therein. In order to capture a mobile terminated 1x call, the hybrid AT closes the HRPD connection and tunes to 1x network. Thus, instead of handover, the prior art accomplishes switching. Here the coordination between the two networks is established at the HAT level only and therefore the AT looks for both the network messages by doing time multiplexing. It is understood that the current architecture does not confer any direct communication between 1x and HRPD networks and the HAT is made intelligent to have the basic interlocking. Figure 1 gives the current network architecture for a Hybrid Access Terminal (HAT). Even though the inter-RAT communication is made possible by the prior art method this approach has its own limitations and disadvantages. The major drawback is that the switching to 1x control channel leads to loss of throughput as the AT has to communicate to the HRPD network to stop sending data for that duration. Thus there are periods of no transmissions for the HRPD network for this AT. Another problem is that the active data session handoff across the RAT is not possible in the present art. This means that connection opened in one kind of network has to be turned off before taking up the new call in the other network. It is also a limitation of the prior art that there are no methods available to inform the network of the movement of the AT to the other network and the information of other system pilots are not communicated to the network. Consequently the pilots that are already measured are not utilized between AT and HRPD for active session handoff. Yet another failure of the architecture is that there is no mechanism to get the HRPD page when AT is tuned to 1x system. The present invention proposes to eliminate the drawbacks of the current technology using a system, which bestows cross paging and Inter-RAT data session handoff for a multi mode (hybrid) AT operating between HRPD and CDMA2000 1x networks, depending on the MS RAT capabilities, MS location, Network condition (Pilot strength etc.), RAT coverage profile etc. suitably analysed and interpreted by an Inter Working Function (IWF). SUMMARY OF THE INVENTION The primary object of this invention is therefore to provide a system for cross paging and inter- RAT data session handoff between HRPD and CDMA2000 1x networks in dormant as well as active session. It is another object of the invention to facilitate architecture for inter-RAT handovers in wireless domain for multi mode AT depending on the MS RAT capabilities, MS location, Network condition (Pilot strength etc.), RAT coverage profile etc. It is a further object of the invention to provide a communication system where AT knows about the RAT deployment in its service area and Mobile Switching Centre (MSC) knows the serving RAT and network details for the AT with the help of an inter working solution (IWS) which has the intelligence to decipher the 1x pilot information for translating 1x messages in CDMA2000 LAC format and to interpret the interface with MSC viz. A1 interface. It is yet another object of the invention to provide a system where MSC can talk to HRPD Access Network via IWS and can query/update the network element (HLR) for serving RAT and network details for the AT. Accordingly, this invention provides a system for cross paging in a Hybrid Access Terminal (HAT) and inter- RAT data session handoff between networks using an Inter Working Solution (IWS) and a new interface (H1) between Mobility Management entity of AN and IWS, the system comprising a) means for receiving an in-coming call for the Hybrid Access Terminal (HAT) that is tuned to an Access Network (AN) and is under the control of the IWS; b) means for sending a paging request message to IWS on receiving the said call by Mobile Switching Centre (MSC); c) means for processing of the said Paging Request message by IWS and generating an encapsulated PDU containing a General Page Message (GPM); d) means for sending the said encapsulated GPM to the AN and then to the HAT; e) means for acknowledging the receipt of encapsulated GPM message by HAT; f) means for sending a response message to the IWS by AN so as to indicate that the HAT successfully received the encapsulated GPM; and g) means for a Paging Response message to the MSC by IWS. These and other objects, features and advantages of the present invention will become clearly apparent from the following description of the embodiments of the invention given as non-restrictive example only and represented in the accompanying drawings. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS Figure 1 portrays the prior art network architecture with hybrid AT. Figure 2 depicts the network architecture of the invention with a proposed new node named IWS (Inter Working Solution) to handle cross paging and handoff between the two kinds of network interfaces. Figure 3 shows the stack required at IWS node and how this stack fits in TIA-878 architecture. Figure 4 presents an example of call flow for a Mobile Terminated call for TIA-878 architecture. DETAILED DESCRIPTION OF THE INVENTION A preferred embodiment of the present invention will now be explained with reference to the accompanying drawings. It should be understood however that the disclosed embodiment is 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. It is to be noted that the existing standardized HRPD Air interface (C.S0024) is used for communication between HAT (Hybrid Access Terminal) and the HRPD RAN (Radio Access Network). Similarly the existing standardized CDMA2000 Air interface (C.S0001 to C.S0005) is used for communication between HAT and the CDMA2000 1x network. Figure 1 shows the current network architecture with hybrid AT. The AT maintains two separate stacks and the interaction between air interfaces for the two is non-existent. The coordination between the two networks is done at the HAT level only and thus it looks for both the network messages by doing time multiplexing. The interfaces defined in the standard are described below. A1 The A1 interface carries signaling information between the call control and mobility management functions of the MSC and the call control component of the BS (Base Station Controller - BSC used in 1x network for Access network). [More clearly shown in Fig 2] A3 The A3 interface is used to transport user traffic and signaling for inter-BS soft/softer handoff when a target BS is attached to the frame selection function within the source BS. The A3 interface carries coded user information (voice/data) and signaling information between the source BS SDU function and the channel element component (BTS) of the target BS. This is a logical description of the endpoints of the A3 interface. The physical endpoints are beyond the scope of this specification. The A3 interface is composed of two parts: signaling and user traffic. The signaling information is carried across a separate logical channel from the user traffic channel, and controls the allocation and use of channels for transporting user traffic. A7 The A7 interface carries signaling information between a source BS and a target BS for inter-BS soft/softer handoff. A9 The A9 interface carries signaling information between the BS and the PCF. A11 The A11 interface carries signaling information between the PCF and the PDSN (Packet Data Switching Node) The invention introduces a new entity called IWS (Inter Working Solution) as part of the HRPD RAN. The IWS interfaces to the MSC via an lOS A1 interface, and also to the SC/MM via a new interface called H1 interface. Figure 2 depicts how the IWS entity would fit in either the TIA-878 or the TIA-1878 architecture. Note that the figure only shows signaling interfaces, and not all interfaces. The new architecture entities are detailed below. IWS (Inter-Working Solution): This entity is made as a part of the HRPD RAN and it interfaces to the MSC via an lOS A1 interface, and also to the SC/MM (Session Control/ Mobility Management) via a new interface called H1 Interface. The SC/MM may be located in either the AN or the PCF (Packet Control Function) in the HRPD RAN. The primary function of the IWS is to translate A1 messages to CDMA2000 LAC messages, which are then sent to the SC/MM for eventual transmission to the HAT. If the SC/MM is located in the AN, then AN will send the message directly to the HAT using the 3G1x Services Notification Application protocol. If the SC/MM is in the PCF, the SC/MM must first send the CDMA2000 LAC message to the AN over the A14 interface. Likewise, messages received from the HAT (such as Connection Request messages) by the AN may result in the SC/MM sending update messages to the IWS; the IWS may then send an A1 interface message (e.g. Location Updating Request) to the MSC. H1 Interface: It is a new interface incorporated between the IWS and the SC/MM. The protocol stack is based on TCP/IP with an lOS layer above that. This IP-based interface connects the IWS to the SC/MM in the HRPD architecture and carries 3G1X LAC encapsulated PDUs in an lOS-defined protocol. Messages carry the encapsulated 3G LAC messages for delivery to the SC/MM and information from the SC/MM to the IWS. Now Referring to Figure 2 the network architecture of the system according to the invention is explained. In the Figure 201 refers to the new node named IWS (Inter-working Solution) that is a part of the HRPD RAN. The new entity viz. IWS, works as the gateway and translator for HRPD network. The 1x network entity viz. MSC sees this IWS as another 1x BSC and pushes relevant messages/data to it. The IWS translates the A1 interface data to one that is understood by HRPD AN (SC/MM entity). The messages from 1x are interpreted by IWS and forwarded to HRPD AN for final delivery to Hybrid AT over HRPD air interface. Similarly messages/data to be sent to 1x network is routed through the IWS and are translated from HRPD format to A1 interface format. 202 refers to the new H1 interface between the IWS and the AN for TIA-878 architecture where SC/MM is part of AN. Similarly 203 refers to the new H1 interface between the IWS and the PCF for TIA-1878 architecture where SC/MM is part of PCF. It is clear from the drawing that the information from SC/MM is transmitted to AN on A14 interface for final delivery to HAT using 3G1x Notification service. Figure 3 shows the protocol stacks for the architecture based on TIA-878. In the figure 301 refers to the stack requirement at IWS to cater for HI interface with HRPD network and A1 interface with MSC. The protocol is almost same for the architecture based on TIA-1878. The only change would be that the SC/MM would be in the PCF where an A14 interface is present between the PCF and the AN. A portrait of call flow for Mobile Terminated (MT) voice-call in HRPD network can be seen in Figure 4. The flow involves the following operation: a) MSC receives an in-coming call for a HAT that it knows is currently tuned to an HRPD AN, which is under control of the IWS. The MSC sends an lOS A1 Paging Request message to the IWS. [This message may or may not contain the Calling Party Number] b) The IWS processes the Paging Request messages and generates a 3G1X LAC encapsulated PDU containing a General Page Message (GPM). The GPM may or may not include the Calling Party Number, depending on whether the IWS received this information from the MSC, The IWS sends the encapsulated GPM to the AN, which currently controls the HAT. c) The AN sends the GPM to the HAT over the TIA-878-A air interface using the 3G 1x Circuit Services Notification Application protocol. d) The HAT acknowledges the receipt of the encapsulated GPM message. e) The AN sends a response message to the IWS indicating that the HAT successfully received the encapsulated GPM. f) The IWS sends a Paging Response message to the MSC. Different techniques are provided in the present invention for handoff between CDMA2000 and HRPD networks. The following information is to be used to read the MSC: • IWS (in conjunction with HRPD AN), appears like a 1x BSC to the MSC. Hence there are no anticipated changes at MSC. • The procedures for MS to clamp on to HRPD/1x after power-up are not depicted as present scope. • The MSC stores the Point Code for the Node (BSC or IWF) to send information to the node serving the MS over SS& link. • The radio measurements at MS trigger the move to 1x network. • The radio measurements or a data call to be serviced by HRPD network triggers the movement to HRPD network. • The IWS (Inter Working Solution) works as plug and play module/node in the network. The IWS is a logical entity in the CDMA2000 network architecture as part of HRPD network. While the foregoing description assumed a particular architecture it will be appreciated that the present invention may be used in numerous architectures and in numerous other examples. The major advantage of the invention is that the nodes/interfaces of the two existing technologies viz. HRPD and 1x that are already developed and deployed can be re-used to provide the provision of inter-working between the two with dormant and active session handoff so as to enable the operator to give better services to its end user especially for data services. The only modification in the architecture is to add new elements/modules at some nodes in the two networks and some new signaling messages in the existing interfaces. 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. WE CLAIM 1. A system for cross paging in a Hybrid Access Terminal (HAT) and inter- RAT data session handoff between networks using an Inter Working Solution (IWS) and a new interface (H1) between Mobility Management entity of AN and IWS, the system comprising; a) means for receiving an in-coming call for the Hybrid Access Terminal (HAT) that is tuned to an Access Network (AN) and is under the control of the IWS; b) means for sending a paging request message to IWS on receiving the said call by Mobile Switching Centre (MSC); c) means for processing of the said Paging Request message by IWS and generating an encapsulated PDU containing a General Page Message (GPM); d) means for sending the said encapsulated GPM to the AN and then to the HAT; e) means for acknowledging the receipt of encapsulated GPM message by HAT; f) means for sending a response message to the IWS by AN so as to indicate that the HAT successfully received the encapsulated GPM; and g) means for a Paging Response message to the MSC by IWS. 2. The system according to claim 1, wherein IWS has the intelligence to interpret the interface (A1) with MSC. 3. The system according to claim 1 wherein the networks are HRPD and CDMA2000 1x. 4. The system according to any of the preceding claims wherein IWS talks to HRPD AN (SC/MM) via H1 interface. 5. The system according to claim 1 wherein the HAT is tuned to HRPD. 6. The system according to claim 1 wherein the said paging request message contains calling party number. 7. The system according to claim 1 wherein the said General Page Message (GPM) is 3G1X LAC encapsulated. 8. The system according to claim 7 wherein the said GPM contains calling party number. 9. The system according to claim 1 wherein the Access Network (AN) sends the GPM to the HAT over the TIA-878-A air interface using the 3G 1x Circuit Services Notification Application protocol. 10. The system according to claim 1 wherein the said inter-RAT handoff depends on the MS RAT capabilities, MS location, Pilot strength and RAT coverage profile. 11. The system according to claim 1, wherein MSC queries and updates the network element (HLR) for serving RAT and network details for the AT. 12. The system according to claim 1 wherein IWS translates CDMA2000 1x messages in CDMA2000 LAC format. 13. A system for cross paging in a Hybrid Access Terminal (HAT) and inter- RAT data session handoff between networks using an Inter Working Solution (IWS) and a new interface (HI) between Mobility Management entity of AN and IWS, substantially herein above described and illustrated with reference to the accompanying drawings.

Documents:

617-CHE-2004 AMENDED CLAIMS 26-07-2013.pdf

617-CHE-2004 AMENDED PAGES OF SPECIFICATION 26-07-2013.pdf

617-CHE-2004 CORRESPONDENCE OTHERS 26-07-2013.pdf

617-CHE-2004 CORRESPONDENCE OTHERS 09-07-2013.pdf

617-CHE-2004 EXAMINATION REPORT REPLY RECEIVED 27-06-2013.pdf

617-CHE-2004 FORM-1 26-07-2013.pdf

617-CHE-2004 OTHER PATENT DOCUMENT 27-06-2013.pdf

617-CHE-2004 OTHERS 09-07-2013.pdf

617-CHE-2004 POWER OF ATTORNEY 09-07-2013.pdf

617-CHE-2004 POWER OF ATTORNEY 26-07-2013.pdf

617-CHE-2004 POWER OF ATTORNEY 27-06-2013.pdf

617-CHE-2004 AMENDED CLAIMS 27-06-2013.pdf

617-CHE-2004 AMENDED PAGES OF SPECIFICATION 27-06-2013.pdf

617-CHE-2004 FORM-1 27-06-2013.pdf

617-CHE-2004 FORM-13 19-06-2006.pdf

617-CHE-2004 FORM-13 27-06-2013.pdf

617-che-2004-abstract.pdf

617-che-2004-claims.pdf

617-che-2004-correspondnece-others.pdf

617-che-2004-description(complete).pdf

617-che-2004-description(provisional).pdf

617-che-2004-drawings.pdf

617-che-2004-form 1.pdf

617-che-2004-form 26.pdf

617-che-2004-form 5.pdf