PATENT DOCUMENT

Publication Number: US-10039037-B2
Application Number: US-201715468214-A
Country: US
Kind Code: B2

Title: Method and apparatus for performing handover in a wireless communication system

Abstract:
A method for performing handover by wireless User Equipment (UE) is provided. The UE includes a Long Term Evolution-Mobile Extreme Convergence (LTE-MXC) application processor, a LTE processor and a Digital Signal Processor (DSP). The UE buffers a set of IP packets when a Radio Access Technology (RAT) indicator is less than a pre-defined threshold and sends the set of IP packets to the LTE processor and the DSP. The LTE processor transmits the set of IP packets to the LTE network and sends acknowledgement signals to the LTE-MXC application processor and the DSP. When the handover is complete, the LTE processor sends the transmission status of the set of IP packets to the DSP. The UE also includes multimode Radio Resource Control (RRC) and Non-Access Stratum (NAS) modules.

Claims:
The invention claimed is: 
     
       1. An apparatus, comprising:
 a memory; and 
 a baseband processor coupled to the memory, wherein the baseband processor and the memory are configured to:
 establish a connection with a first radio access network (RAN) configured according to a first radio access technology (RAT); 
 receive first internet protocol (IP) packets at a packet data convergence layer protocol (PDCP) module of the baseband processor; 
 receive, at a radio resource control (RRC) module, a RAT indicator that indicates policies including measurement control, mobility management, radio resource management, or setting up of channels; 
 establish a connection with a second RAN configured according to a second RAT as part of a handover from the first RAT; 
 transmit IP packets via the second RAN, wherein the IP packets are a set of buffered IP packets determined by transmission status of individual IP packets over a first RAN, and wherein buffering of the IP packets occurs substantially upon the detection of a particular RAT indicator. 
 
 
     
     
       2. The apparatus of  claim 1 ,
 wherein the set of buffered IP packets comprises IP packets that were not transmitted over the connection with the first RAN due at least in part to the handover from the first RAN to the second RAN. 
 
     
     
       3. The apparatus of  claim 1 ,
 wherein IP packets are dropped from the set of buffered IP packets based at least in part on received acknowledgement signals from the first RAN. 
 
     
     
       4. The apparatus of  claim 1 ,
 wherein the handover is initiated by the first RAN. 
 
     
     
       5. The apparatus of  claim 4 ,
 wherein the baseband processor and the memory are further configured to:
 transmit IP packets to the first RAN prior to handover being initiated. 
 
 
     
     
       6. The apparatus of  claim 1 ,
 wherein the baseband processor and the memory are further configured to:
 monitor the RAT indicator, wherein the detection of the particular RAT indicator occurs when the monitored RAT indicator is less than a pre-defined threshold. 
 
 
     
     
       7. The apparatus of  claim 1 ,
 wherein transmission status of individual IP packets includes information about one or more IP packets that were not successfully transmitted to the first RAN. 
 
     
     
       8. The apparatus of  claim 1 ,
 wherein the first RAN comprises a Long Term Evolution (LTE) enabled network, and the second RAN comprises a Universal Mobile Telecommunication System (UMTS) enabled network. 
 
     
     
       9. A mobile device, comprising:
 at least one antenna; and 
 at least one processor coupled to the at least one antenna, wherein the at least one processor is configured to:
 establish a connection with a first radio access network (RAN) configured according to a first radio access technology (RAT); 
 receive first internet protocol (IP) packets at a packet data convergence layer protocol (PDCP) module of a baseband processor; 
 receive, at a radio resource control (RRC) module, a RAT indicator that indicates policies including measurement control, mobility management, radio resource management, or setting up of channels; 
 establish a connection with a second RAN configured according to a second RAT as part of a handover from the first RAT; 
 transmit IP packets via the second RAN, wherein the IP packets are a set of buffered IP packets determined by transmission status of individual IP packets over a first RAN, and wherein buffering of the IP packets occurs substantially upon detection of a particular RAT indicator. 
 
 
     
     
       10. The mobile device of  claim 9 ,
 wherein the set of buffered IP packets comprises IP packets that were not transmitted over the connection with the first RAN due at least in part to the handover from the first RAN to the second RAN. 
 
     
     
       11. The mobile device of  claim 9 ,
 wherein IP packets are dropped from the set of buffered IP packets based at least in part on received acknowledgement signals from the first RAN. 
 
     
     
       12. The mobile device of  claim 9 ,
 wherein the handover is initiated by the first RAN. 
 
     
     
       13. The mobile device of  claim 12 ,
 wherein the at least one processor is further configured to:
 transmit IP packets to the first RAN prior to handover being initiated. 
 
 
     
     
       14. The mobile device of  claim 9 ,
 wherein the at least one processor is further configured to:
 monitor the RAT indicator, wherein the detection of the particular RAT indicator occurs when the monitored RAT indicator is less than a pre-defined threshold. 
 
 
     
     
       15. The mobile device of  claim 9 ,
 wherein transmission status of individual IP packets includes information about one or more IP packets that were not successfully transmitted to the first RAN. 
 
     
     
       16. The mobile device of  claim 9 ,
 wherein the first RAN comprises a Long Term Evolution (LTE) enabled network, and the second RAN comprises a Universal Mobile Telecommunication System (UMTS) enabled network. 
 
     
     
       17. A method for performing handover of a mobile device between a first radio access network (RAN) and a second RAN, the method comprising:
 a baseband processor of the mobile device performing,
 establishing a connection with a first radio access network (RAN) configured according to a first radio access technology (RAT); 
 receiving first internet protocol (IP) packets at a packet data convergence layer protocol (PDCP) module of a baseband processor; 
 receiving, at a radio resource control (RRC) module, a RAT indicator that indicates policies including measurement control, mobility management, radio resource management, or setting up of channels; 
 establishing a connection with a second RAN configured according to a second RAT as part of a handover from the first RAT; 
 transmitting IP packets via the second RAN, wherein the IP packets are a set of buffered IP packets determined by transmission status of individual IP packets over a first RAN, and wherein buffering of the IP packets occurs substantially upon detection of a particular RAT indicator. 
 
 
     
     
       18. The method of  claim 17 ,
 wherein the set of buffered IP packets comprises IP packets that were not transmitted over the connection with the first RAN due at least in part to the handover from the first RAN to the second RAN. 
 
     
     
       19. The method of  claim 17 ,
 wherein IP packets are dropped from the set of buffered IP packets based at least in part on received acknowledgement signals from the first RAN. 
 
     
     
       20. The method of  claim 17 ,
 wherein the handover is initiated by the first RAN.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 15/206,389, filed Jul. 11, 2016, entitled “METHOD AND APPARATUS FOR PERFORMING HANDOVER IN A WIRELESS COMMUNICATION SYSTEM”, now U.S. Pat. No. 9,622,130, which is a continuation of U.S. patent application Ser. No. 14/962,186, filed Dec. 8, 2015, entitled “METHOD AND APPARATUS FOR PERFORMING HANDOVER IN A WIRELESS COMMUNICATION SYSTEM”, now U.S. Pat. No. 9,414,274, which is a continuation of U.S. patent application Ser. No. 13/493,927, filed Jun. 11, 2012, entitled “METHODS AND APPARATUS FOR PERFORMING HANDOVER BETWEEN A LONG TERM EVOLUTION (LTE) NETWORK AND ANOTHER TYPE OF RADIO ACCESS NETWORK”, now U.S. Pat. No. 9,237,495, which is a continuation of U.S. patent application Ser. No. 12/400,834, filed Mar. 10, 2009, entitled “METHODS AND APPARATUS FOR PERFORMING HANDOVER BETWEEN A LONG TERM EVOLUTION (LTE) NETWORK AND ANOTHER TYPE OF RADIO ACCESS NETWORK”, now U.S. Pat. No. 8,199,719, which claims priority to Indian Patent Application No. 633/DEL/2008, filed Mar. 13, 2008, the entirety of which are incorporated herein by reference. 
    
    
     The claims in the instant application are different than those of the parent/grandparent applications and/or other related applications. The Applicant therefore rescinds any disclaimer of claim scope that may have been made in a parent/grandparent application and/or any predecessor application in relation to the instant application. Any such previous disclaimer and the cited references that it was made to avoid, may need to be revisited. Further, any disclaimer made in the instant application should not be read into or against any parent/grandparent applications and/or other related applications. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to wireless communication systems. In particular, the present invention relates to a method and apparatus for performing a handover between a Long Term Evolution (LTE) network and a second generation (2G)/third generation (3G) radio access network. 
     The advances made in wireless communication technology have resulted in the development of numerous mobile communication standards. These standards are broadly categorized into second generation (2G), third generation (3G) and the future, fourth generation (4G) technologies. Examples of 2G/3G technologies include Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), Enhanced Data rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS), and the like. The UMTS standard evolved to LTE technology under the Third Generation Partnership Project (3GPP). LTE technology offers a wireless broadband system with higher data rates, lower latency, and higher spectrum efficiency. It is expected that LTE networks will be deployed in densely populated geographical areas, in the initial phases. Thus, mobile terminals may have to perform handover between the LTE networks and the 2G/3G networks so that users can seamlessly move across geographical areas covered by different networks without an interruption in communication. 
     Certain mobile terminals available today are capable of operating in LTE as well as 2G/3G networks. These mobile terminals employ multiple protocol stacks for wireless communication. Due to the employment of multiple protocol stacks, these mobile terminals can perform a handover between the LTE network and the 2G/3G network. However, the presence of the multiple protocol stacks increases the architectural complexity of the mobile terminals. While the handover is being performed, some of the IP packets generated by the applications running on these mobile terminals may not reach their destination. These IP packets are either lost during their transmission over the wireless connection or are not transmitted by the mobile terminals due to the absence of a free channel. Further, after the handover is complete, some of these IP packets belonging to delay sensitive applications may not be retransmitted by the mobile terminals as it may be too late to transmit those packets. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following detailed description of the preferred embodiments of the present invention will be better understood when read in conjunction with the appended drawings. The present invention is illustrated by way of example, and not limited by the accompanying figures, in which like references indicate similar elements. 
         FIG. 1  is a schematic diagram illustrating an exemplary environment in which the present invention can be practiced, in accordance with an embodiment of the present invention. 
         FIG. 2  is a block diagram illustrating the architecture of a wireless User Equipment (UE), in accordance with an embodiment of the present invention. 
         FIG. 3  is a block diagram illustrating the architecture of the wireless UE, in accordance with another embodiment of the present invention. 
         FIG. 4  is a block diagram illustrating the architecture of the wireless UE, in accordance with yet another embodiment of the present invention. 
         FIG. 5  is a block diagram illustrating the operating states of a multi-mode Radio Resource Control (MMd_RRC) module, in accordance with an embodiment of the present invention. 
         FIG. 6  is a block diagram illustrating the operating states of the MMd_RRC module, in accordance with another embodiment of the present invention. 
         FIG. 7  is a block diagram illustrating the operating states of a multi-mode Non-Access Stratum (MMd_NAS) module, in accordance with an embodiment of the present invention. 
         FIG. 8  is a flow diagram illustrating a method for performing a handover between a LT) network and a 2G/3G network, in accordance with an embodiment of the present invention. 
         FIGS. 9, 10 and 11  are a flow diagram illustrating a method for performing the handover between the LTE network and the 2G/3G network, in accordance with another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The detailed description of the appended drawings is intended as a description of the currently preferred embodiments of the present invention, and is not intended to represent the only form in which the present invention may be practiced. It is to be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present invention. 
     In an embodiment of the present invention, a method for performing a handover by a wireless user equipment (UE) is provided. The wireless UE includes a Long Term Evolution-Mobile Extreme Convergence (LTE-MXC) application processor, an LTE processor and a Digital Signal Processor (DSP) supporting MXC modem (UMTS/GSM) functionality. The MXC platform is a mobile phone architecture that separates the domain of application processing from the domain of communication (modem). This separation helps the developers to develop and continuously update applications without modifying the modem. The wireless UE communicates with a wireless communication system that includes a plurality of Radio Access Networks (RANs). One of the RANs is a LTE network. The wireless UE buffers a set of IP packets when a Radio Access Technology (RAT) indicator is less than a pre-defined threshold. When the handover is initiated, the set of IP packets is sent to the LTE processor and the DSP. The LTE processor transmits the set of IP packets to the LTE network via a wireless connection between the wireless UE and the LTE network. Further, the LTE processor sends acknowledgement signals to the LTE-MXC application processor and the DSP. The acknowledgement signals indicate a successfully transmitted subset of IP packets. The successfully transmitted subset of IP packets includes IP packets that are received by the LTE network without getting lost during their transmission over the wireless connection. The successfully transmitted subset of IP packets are positively acknowledged of being received, by the LTE network to the wireless UE. When the handover is complete, the LTE processor sends messages to the DSP and LTE-MXC application processor. At least one of the messages indicates the transmission status of the set of IP packets. The transmission status indicates a subset of IP packets that has not been successfully transmitted by the LTE processor to the LTE network. The subset of IP packets includes IP packets that were not positively acknowledged of being received, by the LTE network to the wireless UE. The subset of IP packets also includes IP packets that were buffered at the LTE processor but could not be transmitted by the LTE processor over the wireless connection due to the handover. Once the handover is complete, the DSP transmits the subset of IP packets to one of the plurality of RANs based on the transmission status received from the LTE processor. 
     In another embodiment of the present invention, a wireless UE is provided. The wireless UE communicates with a wireless communication system that includes a plurality of RANs. One of the RANs is a LTE network. The wireless UE includes a multi-mode Radio Resource Control (MMd_RRC) module, a multi-mode Non-access Stratum (MMd_NAS) module, a LTE-MXC application processor, an LTE processor and a DSP. The MMd_RRC module establishes a wireless connection between the wireless UE and at least one of the plurality of RANs. The MMd_NAS module establishes a wireless connection between the wireless UE and at least one of a core network providing circuit-switched services and a core network providing packet-switched services. The LTE-MXC application processor facilitates the generation, buffering and sending of IP packets. The LTE processor is operatively coupled to the LTE-MXC application processor and receives IP packets from the LTE-MXC application processor, sends messages to the LTE-MXC application processor and transmits IP packets to the LTE network. The DSP is operatively coupled to the LTE-MXC application processor and the LTE processor. The DSP receives IP packets from the LTE-MXC application processor, receives messages from the LTE processor and LTE-MXC application processor, and transmits IP packets to one of the plurality of RANs based on the received messages. 
     In yet another embodiment of the present invention, a wireless UE is provided. The wireless UE includes a LTE-MXC application processor, an LTE processor and a DSP supporting MXC modem (UMTS/GSM) functionality. The wireless UE also includes a multi-mode RRC (MMd_RRC) module and a multi-mode NAS (MMd_NAS) module. The MMd_RRC module operates in an MMd_RRC_detached state, an MMd_RRC_connected state and an MMd_RRC_idle state. In the MMd_RRC_detached state, the MMd_RRC module monitors a Radio Access Technology (RAT) indicator and establishes a wireless connection between the wireless UE and at least one of the wireless networks (an LTE cell, a UMTS cell and a GSM cell) in the vicinity of the wireless UE based on the RAT indicator. By establishing the wireless connection for data communication the MMd_RRC module performs a state transition to the MMd_RRC_connected state. 
     In the MMd_RRC_connected state, the MMd_RRC module performs a handover from an LTE_connected state to a UTRAN_connected state and vice-versa, performs a handover from the LTE_connected state to a GSM_connected state and vice-versa, and performs a handover from the LTE_connected state to the GSM_connected state via a GPRS_Packet_Transfer_Mode state and vice versa. Further, the MMd_RRC module performs a handover from the LTE_connected state to the GPRS_Packet_Transfer_Mode state and vice-versa, and performs a handover from the UTRAN_connected state to the GSM_connected state and vice-versa. 
     The MMd_RRC module performs a state transition to the MMd_RRC_idle state when there is no activity on the connected wireless network (i.e., one of the LTE cell, the UMTS cell and the GSM cell) for the wireless UE for a time period greater than a first predefined time threshold. The MMd_RRC module performs a state transition to the MMd_RRC_detached state when the wireless connection between the wireless UE and connected wireless network is released. 
     In the MMd_RRC_idle state, the MMd_RRC module performs a state transition to the MMd_RRC_detached state and performs a state transition to the MMd_RRC_connected state when there is new activity on at least one of the wireless networks. 
     The MMd_NAS module operates in an MMd_NAS_detached state, an MMd_NAS_connected state, and an MMd_NAS_idle state. 
     In the MMd_NAS_detached state the MMd_NAS module establishes a wireless connection between the wireless UE and at least one of a core network providing circuit-switched services and a core network providing packet-switched services. 
     In the MMd_NAS_connected state, when the wireless UE is connected to the core network providing packet/circuit switched services, the MMd_NAS module performs a state transition to the MMd_NAS_idle state when the wireless connection between the wireless UE and one of the core networks is released. Further, the MMd_NAS module, when connected to the LTE network, performs a state transition to the MMd_NAS_idle state when an LTE network is inactive for a time period greater than a third predefined time threshold and performs a state transition to the MMd_NAS_detached state when the wireless connection between the wireless UE and the LTE network is released. 
     In the MMd_NAS_idle state, when wireless UE is in an LTE_Idle state, the MMd_NAS module performs a state transition to the MMd_NAS_connected state when there is new activity on the wireless connection between the wireless UE and the LTE network. Further, the MMd_NAS module performs a state transition to the MMd_NAS_connected state when the wireless connection between the wireless UE and at least one of the core network providing circuit-switched services and the core network providing packet-switched services is established, and performs a state transition to the MMd_NAS_detached state. 
     Referring now to  FIG. 1 , a schematic diagram illustrating an exemplary wireless communication system  102  with a wireless UE  104  is shown, in accordance with an embodiment of the present invention. Examples of the wireless UE  104  include a cellular phone, a smart phone, a Personnel Digital Assistant (PDA), a pager, a handheld computer and so forth. The wireless UE  104  is capable of operating within various RANs. The wireless communication system  102  includes an LTE network  106  and a RAN  108 . Examples of the RAN  108  include, but are not limited to a 2G/3G radio access network like a GSM radio access network (GRAN), Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), an Enhanced Data Rates for GSM Evolution (EDGE) Radio Access Network (GERAN), High Speed Packet Access (HSPA) Network. The wireless UE  104  establishes a wireless connection with either the LTE network  106  or the RAN  108 . The wireless UE  104  also performs a handover between the LTE network  106  and the RAN  108 . 
     Referring now to  FIG. 2 , a block diagram illustrating the architecture of the wireless UE  104  is shown, in accordance with an embodiment of the present invention. The wireless UE  104  includes a LTE-MXC application processor  202 , an Identification Module (IM)  204 , an LTE processor  206  and a Digital Signal Processor (DSP)  208 . The LTE-MXC application processor  202  is used for developing and executing applications. These applications can be multimedia applications that require very high data rates for providing multimedia data to the users in real-time. Examples of the multimedia applications include video conferencing, image processing applications, video playback, push-to-talk applications and the like. The LTE-MXC application processor  202  facilitates the generation, buffering and sending of IP packets to the LTE processor  206  and the DSP  208 . The LTE-MXC application processor  202  sends IP packets to the LTE processor  206  or the DSP  208 , when the wireless UE  104  is operating in the LTE network  106  or the RAN  108  respectively. The LTE-MXC application processor  202  stores IP packets in a buffer and sends IP packets to both the LTE processor  206  and the DSP  208  when the handover of the wireless UE  104  is initiated between the LTE network  106  and the RAN  108 . In this embodiment, the LTE-MXC application processor  202  further receives messages from the LTE processor  206 . Based on the received messages, the LTE-MXC application processor  202  drops IP packets. Dropping IP packets refers to deleting IP packets from the buffer. In one embodiment, the LTE-MXC application processor  202  is an Advanced RISC Machine (ARM™) application processor. 
     The Identification Module (IM)  204  contains data pertaining to the wireless UE  104  so that the wireless UE  104  can be authenticated by the LTE network  106  and the RAN  108 . Based on the authentication, the wireless UE  104  connects to the LTE network  106  and the RAN  108 . In an embodiment of the present invention, the wireless UE  104  is capable of operating in the LTE network  106  and the RAN  108 . In this embodiment, the IM  204  includes a Subscriber Identification Module (SIM), a Universal Subscriber Identity Module (USIM), an IP Multimedia Services Identity Module (ISIM), and an LTE Subscriber Identity Module (LSIM). The SIM module and the USIM module are used for the authentication of the wireless UE  104  in the GERAN and the UTRAN respectively. The USIM module can also be used for the authentication of the wireless UE  104  in the LTE network  106 . The ISIM module and the LSIM module contain data for the authentication of the wireless UE  104  in the IMS and the LTE network  106  respectively. 
     In one embodiment, the LTE processor  206  receives IP packets from the LTE-MXC application processor  202  and transmits IP packets to the LTE network  106  over a wireless connection. There is the possibility that some of the IP packets will not reach the LTE network  106 , as they are lost during the transmission over the wireless connection. The reasons for this loss can be signal degradation over the wireless connection, an oversaturated wireless connection, IP packets that get corrupted and the like. These lost IP packets are not positively acknowledged of being received, by the LTE network  106  to the wireless UE  104 . Further, in this embodiment, the LTE processor  206  sends messages to the LTE-MXC application processor  202  and the DSP  208 . For example, these messages are acknowledgement signals that indicate successfully transmitted IP packets. The successfully transmitted IP packets are IP packets that were transmitted by the LTE processor  206  and were positively acknowledged of being received, by the LTE network  106  to wireless UE  104 . The messages also include the transmission status of IP packets received by the LTE processor  206 . The transmission status indicates IP packets that were not successfully transmitted by the LTE processor  206  to the LTE network  106 , i.e., the IP packets that were not positively acknowledged of being received, by the LTE network  106  to wireless UE  104 . The transmission status also indicates IP packets that were buffered by the LTE processor  206  but could not be transmitted by the LTE processor  206  over the wireless connection due to the handover from LTE network  106  to the RAN  108 . 
     In one embodiment, the DSP  208  receives IP packets from the LTE-MXC application processor  202  and transmits IP packets to the RAN  108  via a wireless connection. Further, in the one embodiment, the DSP  208  stores IP packets received from the LTE-MXC application processor  202  in a local buffer. In this embodiment, the DSP  208  receives messages from the LTE processor  206 . In one example, the messages are acknowledgement signals that indicate successfully transmitted IP packets that were positively acknowledged of being received, by the LTE network  106  to the wireless UE  104 . Based on the received acknowledgement signals, the DSP  208  drops the successfully transmitted IP packets. Dropping of IP packets refers to deleting the successfully transmitted IP packets from the local buffer in the DSP  208 . After the handover is complete, the DSP  208  receives the transmission status of the IP packets from the LTE processor  206 . Based on the transmission status, the DSP  208  transmits the IP packets that were either transmitted by LTE processor  206  but not positively acknowledged of being received, by the LTE network  106  to the wireless UE  104  or could not be transmitted by the LTE processor  206  due to the handover. In one embodiment, the DSP  208  is a Starcore™ DSP such as the MSC8144 available from Freescale Semiconductor, Inc. 
     The LTE-MXC application processor  202  includes a multi-mode Radio Resource Control (MMd_RRC) module  212  and a multi-mode Non-access Stratum (MMd_NAS) module  214 . The MMd_RRC module  212  and the MMd_NAS module  214  operate using a multi-mode control protocol. The multi-mode control protocol is a single stack protocol that enables the wireless UE  104  to operate in the LTE network  106  and the RAN  108 . The multi-mode control protocol also facilitates the handover of the wireless UE  104  between the LTE network  106  and the RAN  108 . 
     When the wireless UE  104  is switched on, the MMd_RRC module  212  selects a wireless network for establishing a wireless connection between the wireless UE  104  and the selected wireless network. The selected wireless network can either be the RAN  108  or the LTE network  106 . The selection is made based on the signal strength the wireless UE  104  receives from wireless networks ( 106 ,  108 ) in the vicinity of the wireless UE  104 . In one embodiment, the selection can also be based on the policies defined by the user of the wireless UE  104  or the operators of the wireless networks ( 106 ,  108 ). The MMd_RRC module  212  also facilitates performing the handover of the wireless UE  104  between the LTE network  106  and the RAN  108 . Further, in this embodiment, the MMd_RRC module  212  configures a scheduler  216 , a radio link control (RLC) module  218  and the Packet Data Convergence Protocol (PDCP) modules ( 220  and  226 ) to send IP packets generated by the applications running on the LTE-MXC application processor  202  to the LTE processor  206  and the DSP  208 . The MMd_RRC module  212  also facilitates performing policy related functions such as measurement control, mobility management, radio resource management, and setting up of channels. Setting up of channels includes the selection of a specific radio frequency over which the wireless connection is established. 
     In one embodiment, the MMd_NAS module  214  establishes a wireless connection between the wireless UE  104  and a core network that provides packet-switched services. The core network providing packet-switched services routes the IP packets originating from the wireless UE  104  to a destination UE via a channel that is shared with traffic originating from other user equipments (UEs). In this embodiment, the MMd_NAS module  214  also establishes a wireless connection between the wireless UE  104  and another core network that provides circuit-switched services. The core network providing circuit-switched services routes the IP packets originating from the wireless UE  104  to the destination UE via a fixed bandwidth channel that cannot be shared with traffic originating from other UEs. A core network also supports other functionalities such as authentication the wireless UE  104  that requests for a service from the core network, routing and billing calls made by the wireless UE  104 , call waiting and call transfer. 
     The LTE-MXC application processor  202  also includes a Packet Data Convergence Protocol_User Plane (PDCP_U) module  220 , a Common Platform Access Packet Interface (CPA_PI) module  222  and an IP Stack  224 . The IP Stack  224  generates IP packets. The IP packets are sent to the PDCP_U module  220  via the CPA_PI module  222 . The CPA_PI module  222  is used to adapt the architecture of the wireless UE  104  to applications developed using any Operating System (OS). The PDCP_U module  220  performs header compression on the IP packets and sends the compressed IP packets to the RLC module  218 . The RLC module  218  sends the IP packets to the LTE processor  206  or the DSP  208  via the Scheduler  216 . 
     In one embodiment, the LTE-MXC application processor  202  and the LTE processor  206  communicate via a High Speed Universal Serial Bus (USB). The LTE-MXC application processor  202  and the DSP  208  communicate via a Serial Direct Memory Access (S-DMA) link  210 . 
     Referring now to  FIG. 3 , a block diagram illustrating the architecture of a wireless UE  300  is shown, in accordance with another embodiment of the present invention. The architecture is an example of the Mobile Extreme Convergence (MXC) platform architecture. The LTE-MXC application processor  202  and the LTE processor  206  communicate via the Serial Direct Memory Access (S-DMA) link  210 . The S-DMA link  210  blocks the LTE processor  206  as a peripheral device and controls the movement of IP packets from LTE-MXC application processor  202  to the LTE processor  206  and vice-versa. Also, the S-DMA link  210  controls the movement of IP packets from LTE-MXC application processor  202  to the DSP  208  and vice-versa. 
     Referring now to  FIG. 4 , a block diagram illustrating the architecture of a wireless UE  400  is shown, in accordance with yet another embodiment of the present invention. The wireless UE  400  includes an application processor  402 , a LTE-MXC baseband processor  404  and the identification module  204 . The LTE-MXC baseband processor  404  includes the MMd_RRC module  212  and the MMd_NAS module  214 . The architecture shown in  FIG. 4  is an example of the MXC platform architecture. The underlying concept of this architecture is the separation of the two main domains of a wireless communication device: the communication domain (i.e., the modem) and the applications domain. The components of the communication domain (modem) are represented by the LTE-MXC baseband processor  404  that facilitates communication between the wireless UE  400  and the selected wireless network, whereas the components in the applications domain are represented by the application processor  402  that facilitates development and execution of applications. The LTE-MXC baseband processor  404  facilitates buffering and sending IP packets to the LTE network  106  and the RAN  108 . 
     The wireless UE  400  further includes a CPA_Client module  406 , an LTE-3GPP Handover (HO) module  408  and a CPA_Server  410 . The CPA_Client module  406  is operatively coupled to the CPA_Server  410 . The CPA_Client  406  receives IP packets from the IP Stack  224  and sends the received IP packets to the CPA_Server  410 . The CPA_Server  410  translates the IP packets to a format that can be used by the MMd_NAS module  214 . These IP packets are transmitted to the LTE network  106  via an LTE Media Access Control (MAC) module and an LTE Physical (PHY) module collectively represented by  412 . These IP packets can also be transmitted to the RAN  108  via a MAC of 2G/3G networks module and a PHY of 2G/3G networks module collectively represented by  414 . 
     Referring now to  FIG. 5 , a block diagram illustrating the operating states of the MMd_RRC module  212  is shown, in accordance with an embodiment of the present invention. The MMd_RRC module  212  operates in three states an MMd_RRC_detached state  502 , an MMd_RRC_connected state  504  and an MMd_RRC_idle state  506 . When the wireless UE  104  ( 300 ,  400 ) is switched on, it is in the MMd_RRC_detached state  502 . In the MMd_RRC_detached state  502 , the wireless UE  104  is not connected to any of the wireless networks in the vicinity of the wireless UE  104 . In one example, the wireless networks include an LTE cell  510 , an UMTS cell  512  and a GSM cell  514 . The MMd_RRC module  212  selects one of the wireless networks  510 ,  512 ,  514  for establishing a wireless connection between the wireless UE  104  and the selected wireless network. The selection is made based on the monitoring of a RAT indicator  508 . The RAT indicator  508  indicates the signal strength the wireless UE receives from the wireless networks  510 ,  512 ,  514 . In one embodiment, the RAT indicator  508  indicates the policies made by the user of the wireless UE  104  or the operators of the wireless networks  510 ,  512 ,  514 . On establishing the wireless connection, the MMd_RRC module  212  makes a state transition to the MMd_RRC_connected state  504 . In the MMd_RRC_connected state  504 , IP packets can be actively transmitted over the wireless connection between the wireless UE  104  and the selected wireless network. 
     In one embodiment, the MMd_RRC module  212  establishes the wireless connection between the wireless UE  104  and the LTE cell  512  by an LTE Registration as indicated by  518 . On establishing the wireless connection the MMd_RRC module  212  performs a state transition to an LTE_connected state  520 . 
     In this embodiment, the MMd_RRC module  212  establishes the wireless connection between the wireless UE  104  and the UMTS cell  512  via an UMTS_RRC_Connection as indicated by  522  and performs a state transition to an UTRAN_connected state  524 . 
     In this embodiment, the MMd_RRC module  212  establishes the wireless connection between the wireless UE  104  and the GSM cell  514  via a GSM_RRC_Connection as indicated by  526  and performs a state transition to a GSM_connected state  528 . The GSM cell  514  also supports GPRS  516  that enables data transfer over the wireless connection between the wireless UE  104  and the GSM cell  514 . On the initiation of a data session as indicated by  530 , the MMd_RRC module  212  performs a state transition to a GPRS_Packet_Transfer_Mode  532 . 
     In one embodiment, the MMd_RRC module  212  performs a state transition to the MMd_RRC_connected state  504  by Cell Reselection as indicated by  534  to select one of the wireless networks  510 ,  512  and  514  for the wireless connection. 
     The wireless UE  104  can also perform a handover (LTE-UMTS HO) from the LTE cell  510  to the UMTS cell  512  when the MMd_RRC module  212  performs a state transition from the LTE_connected state  520  to the UTRAN_connected state  524 , and vice versa. 
     In this embodiment, the wireless UE  104  performs a handover (LTE-GSM HO I) from the LTE cell  510  to the GSM cell  514  when the MMd_RRC module  212  performs a state transition from the LTE_connected state  520  to the GSM_connected state  528 , and vice versa. 
     The wireless UE  104  performs a handover (LTE-GSM HO II) from the LTE cell  510  to the GSM cell  514  when the MMd_RRC module  212  performs a state transition from the LTE_connected state  520  to the GSM_connected state  528  via the GPRS_Packet_Transfer_Mode  532 , and vice versa. 
     The wireless UE  104  performs a handover (LTE-GPRS HO) from the LTE cell  510  to the GSM cell  514  when the MMd_RRC module  212  performs a state transition from the LTE_connected state  520  to the GPRS_Packet_Transfer_Mode  532 , and vice versa. 
     The wireless UE  104  performs a handover (UMTS-GSM HO) from the UMTS cell  512  to the GSM cell  514  when the MMd_RRC module  212  performs a state transition from the UTRAN_connected state  524  to the GSM_connected state  528 , and vice versa. 
     The MMd_RRC module  212  also performs a state transition from the MMd_RRC_connected state  504  to the MMd_RRC_detached state  502  by a LTE Deregistration as indicated by  518 , release of the UMTS_RRC_Connection as indicated by  522 , release of the GSM_RRC_Connection as indicated by  526  or end of the data session as indicated by  530 . 
     In the MMd_RRC_idle state  506 , only the control signals can be transmitted over the wireless connection between the wireless UE  104  and the selected wireless network. 
     In one embodiment, the MMd_RRC module  212  performs a state transition from MMd_RRC_connected state  504  to the MMd_RRC_idle state  506  when there is inactivity as indicated by  536  in the selected wireless network for a time period that is greater than a first pre-defined time threshold. Inactivity in the selected wireless network refers to the absence of IP packets for the wireless UE  104  over the wireless connection between the wireless UE  104  and the selected wireless network. The MMd_RRC_idle state  506  includes the LTE_idle state, an UMTS_idle state and a GSM_idle state. In an example, when the selected wireless network is the LTE cell  510 , the MMd_RRC module  212  performs a state transition from LTE_connected state  520  to the LTE_idle state when there is inactivity as indicated by  536  in the LTE cell  510  or a time period that is greater than the first pre-defined time threshold. 
     The MMd_RRC module  212  performs a state transition from MMd_RRC_idle state  506  to the LTE_connected state  520  when there is a new activity as indicated by  538  over the wireless connection between the wireless UE  104  and the selected wireless network  510 . The new activity is determined by an attempt to transmit IP packets between the wireless UE  104  and the selected wireless network. In an example, when the selected wireless network is the LTE cell  510 , the MMd_RRC module  212  performs a state transition from the MMd_LTE_idle state to the LTE_connected state  520  when there is new activity as indicated by  538  over the wireless connection between the wireless UE  104  and the LTE cell  510 . The MMd_RRC module  212  performs a state transition from the MMd_RRC_idle state  506  to the MMd_RRC_detached state  502  when there is a time-out as indicated by  540 . The time-out  540  occurs when there is no new activity over the wireless connection between the wireless UE  104  and the selected wireless network for a time period that is greater than a second pre-defined time threshold. 
     In this embodiment, the UTRAN_connected state  524  includes four substates. The four states are the URA_PCH state, the Cell_PCH state, the Cell_DCH state and the Cell_FACH state. In the Cell_DCH state and the Cell_FACH state, the wireless UE  104  continuously monitors the wireless connection between the wireless UE  104  and the UMTS cell  512  for IP packets. Further, although IP packets are not transmitted between the wireless UE  104  and the UMTS cell  512  in the URA_PCH state and the Cell_PCH state, the wireless UE  104  monitors the wireless connection for paging signals transmitted by the UMTS cell  512 . 
     Referring now to  FIG. 6 , a block diagram illustrating the operating states of the MMd_RRC module  212  is shown, in accordance with another embodiment of the present invention. In this embodiment, the MMd_RRC module  212  operates in three states the MMd_RRC_detached state  502 , the MMd_RRC_connected state  504  and an MMd_RRC_idle_Extended state  602 . The UTRAN_connected state  524  of the MMd_RRC_connected state  504  includes two substates, the Cell_DCH state  604  and the Cell_FACH state  606 . The MMd_RRC_idle_Extended state  602  includes the MMd_RRC_idle state  506 , the URA_PCH state  608  and the Cell_PCH state  610 . This embodiment provides for an efficient implementation of the architecture of the wireless UE  104 . Also, the specifications required for this architecture are simpler. 
     Referring now to  FIG. 7 , a block diagram illustrating the operating states of the MMd_NAS module  214  is shown, in accordance with an embodiment of the present invention. The MMd_NAS module  214  operates in an MMd_NAS_detached state  702 , an MMd_NAS_connected state  704 , and an MMd_NAS_idle state  706 . When the wireless UE  104  is switched on, the MMd_NAS module  214  is in the MMd_NAS_detached state  702 . In the MMd_NAS_detached state  702 , the wireless UE  104  is not connected to the LTE network  106 , a core network providing circuit-switched services or a core network providing packet-switched services. The core network providing packet-switched services can be any 2G/3G packet-switched core network. The MMd_NAS_detached state  702  includes an LTE_Detached state  708  and a Packet Mobility Management (PMM)_Detached state  710 . The wireless UE  104  is not connected to the LTE network  106  in the LTE_Detached state  708 . The wireless UE  104  is not connected to the core network providing packet-switched services in the PMM_Detached state  710 . The MMd_NAS module  214  establishes a wireless connection between the wireless UE  104  and the LTE network  106  by performing an LTE registration as indicated by  712 . On establishing the wireless connection, the MMd_NAS module  214  performs a state transition to an LTE_Active state  714  of the MMd_NAS_connected state  704 . In this embodiment, the MMd_NAS module  214  establishes a wireless connection between the wireless UE  104  and the core network providing packet-switched services by performing a Packet Switch (PS) Attach as indicated by  716 . On establishing the wireless connection, the MMd_NAS module  214  performs a state transition to a PMM_Connected state  718  of the MMd_NAS_connected state  704 . In the PMM_Connected  718 , data packets and control signals can be transmitted over the wireless connection between the wireless UE  104  and the core network providing packet-switched services. 
     In the LTE_Active state  714 , the MMd_NAS module  214  performs a state transition  720  to an LTE_idle state  722  of the MMd_NAS_idle state  706  when the LTE network  106  is inactive for a time period that is greater than a third predefined time threshold. In one embodiment, the MMd_NAS module  214  performs a state transition from the PMM_Connected state  718  to a PMM_Idle state  726  of the MMd_NAS_idle state  706  when a Packet Switched (PS) Signaling Connection is released as indicated by  724 . In the PMM_Idle state  726 , only control signals can be transmitted over the wireless connection between the wireless UE  104  and the core network providing packet-switched services. 
     In one embodiment, the MMd_NAS module  214  performs a state transition from the LTE_idle state  722  to the LTE_Active state  714  when there is a new activity as indicated by  728  over the wireless connection between the wireless UE  104  and the LTE network  106 . Further, the MMd_NAS module  214  performs a state transition from the PMM_Idle state  726  to the PMM_Connected state  718  when a PS Signaling Connection is established as indicated by  730 . Furthermore, the MMd_NAS module  214  performs a state transition from the LTE_idle state  722  to the LTE_Detached  708  when there is a timeout as indicated by  732 . The timeout  732  occurs when there is no new activity on the LTE network  106  for a time period that is greater than a fourth pre-defined time threshold. The MMd_NAS module  214  performs a state transition from the PMM_Idle state  726  to the PMM_Detached  710  by performing a PS Detach as indicated by  734 . 
     In one embodiment, the MMd_NAS module  214  performs a state transition from the LTE_Active state  714  to the LTE_Detached state  708  by performing a LTE Deregistration as indicated by  736 . Further, the MMd_NAS module  214  performs a state transition from the LTE_Active state  714  to the LTE_Detached  708  when there is a change in the Public Land Mobile Network (PLMN) to which the wireless UE  104  belongs as indicated by  736 . 
     Referring now to  FIG. 8 , a flow diagram illustrating a method for performing handover between the LTE network  106  and the 2G/3G RAN  108  is shown, in accordance with an embodiment of the present invention. The method starts at step  802 , where the wireless UE  104  is connected via a wireless connection with the LTE network  106 . 
     At step  804 , the LTE-MXC application processor  202  buffers a set of IP packets by storing the set of IP packets in the buffer when the RAT indicator  508  is less than a pre-defined threshold. In one embodiment, the LTE-MXC application processor  202  buffers the set of IP packets when the signal strength the wireless UE  104  received from the LTE network  106  is below the pre-defined threshold of signal strength. 
     At step  806 , the handover is initiated by the LTE network  106  or by the wireless UE  104 . 
     At step  808 , the LTE-MXC application processor  202  sends the set of IP packets to the LTE processor  206  and the DSP  208 . In one embodiment, the set of IP packets is sent to the LTE processor  206  via a USB. In another embodiment, the set of IP packets is sent to the LTE processor  206  and the DSP  208  via the S-DMA link  210 . 
     At step  810 , the LTE processor  206  transmits the set of IP packets to the LTE network  106  via the wireless connection between the wireless UE  104  and the LTE network  106 . 
     At step  812 , the LTE processor  206  sends acknowledgement signals to the LTE-MXC application processor  202  and the DSP  208 . These acknowledgement signals indicate a successfully transmitted subset of IP packets. The successfully transmitted subset of IP packets includes IP packets that have been positively acknowledged of being received, by LTE network  106  to wireless UE  104 . 
     At step  814 , the LTE processor  206  sends messages to the DSP  208  when the handover is complete after a wireless connection is established between the wireless UE  104  and the RAN  108 . The messages include the transmission status of the set of IP packets received by the LTE processor  206 . In one example, the transmission status indicates a subset of IP packets that was not successfully transmitted by the LTE processor  206  to the LTE network  106 , i.e., the subset of IP packets includes IP packets that have been transmitted by the wireless UE  104  but were not positively acknowledged of being received, by LTE network  106  to wireless UE  104 . The subset of IP packets also includes IP packets that were buffered by the LTE processor but could not be transmitted by the LTE processor  206  to the LTE network  106  due to the handover. 
     At step  816 , the DSP  208  transmits the subset of IP packets to the RAN  108  via the wireless connection between the wireless UE  104  and the RAN  108 . The subset of IP packets is determined by the transmission status the DSP  208  receives from the LTE processor  206 . The method for performing the handover between the LTE network  106  and the RAN  108  then is complete at a step  818 . 
     Referring to  FIGS. 9, 10 and 11 , a flow diagram illustrating a method for performing handover between the LTE network  106  and the 2G/3G RAN  108  is shown, in accordance with another embodiment of the present invention. The method is initiated at step  902 . At step  904 , the LTE-MXC application processor  202  generates a set of IP packets. The set of IP packets is generated by the applications running on the LTE-MXC application processor  202 . 
     At step  906 , the MMd_RRC module  212  of the LTE-MXC application processor  202  monitors the RAT indicator  508  to determine the present value of the RAT indicator  508 . In one embodiment, the MMd_RRC module  212  monitors the signal strength the wireless UE  104  receives from the LTE network  106 . The RAT indicator  508  is continuously monitored. In another embodiment, the RAT indicator  508  is periodically monitored at fixed time of intervals. 
     At step  908 , the MMd_RRC module  212  compares the present value of the RAT indicator  508  with the pre-defined threshold. In one embodiment, the MMd_RRC module  212  compares the signal strength the wireless UE  104  receives from the LTE network  106  with the pre-defined threshold of the signal strength. 
     At step  910 , the LTE-MXC application processor  202  sends the set of IP packets to the LTE processor  206  when the present value of the RAT indicator  508  is greater than the pre-defined threshold. 
     At step  912 , the LTE processor  206  transmits the set of IP packets to the LTE network  106  via the wireless connection between the wireless UE  104  and the LTE network  106 . The method is completed after step  1012 . 
     At step  914 , the LTE-MXC application processor  202  buffers the set of IP packets by storing the set of IP packets in the buffer when the present value of the RAT indicator  508  is less than the pre-defined threshold. 
     At step  1002 , the wireless UE  104  determines whether a handover has been initiated from the LTE network  106  to the RAN  108 . 
     At step  1004 , the LTE-MXC application processor  202  sends the set of IP packets to the LTE processor  206  via the USB when the handover has not been initiated. In another embodiment, the LTE-MXC application processor  202  sends the set of IP packets to the LTE processor  206  via the S-DMA link  210 . 
     At step  1006 , the LTE processor  206  transmits the set of IP packets to the LTE network  106  via the wireless connection between the wireless UE  104  and the LTE network  106 . 
     At step  1008 , the LTE processor  206  sends acknowledgement signals to the LTE-MXC application processor  202 . These acknowledgement signals indicate a successfully transmitted subset of IP packets. The successfully transmitted subset of IP packets are IP packets that were positively acknowledged of being received, by the LTE network  106  to the wireless UE  104 . 
     At step  1010 , the LTE-MXC application processor  202  drops the successfully transmitted subset of IP packets by deleting the successfully transmitted subset of IP packets from the buffer. After step  1110 , the method is completed. 
     At step  1012 , the LTE-MXC application processor  202  sends the set of IP packets to the LTE processor  206  and the DSP  208  when the handover is initiated. 
     At step  1014 , the LTE processor  206  transmits the set of IP packets to the LTE network  106  via the wireless connection between the wireless UE  104  and the LTE network  106 . 
     At step  1016 , the LTE processor  206  sends acknowledgement signals to the LTE-MXC application processor  202  and the DSP  208 . In one embodiment, the acknowledgement signals are sent only to the LTE-MXC application processor  202 . These acknowledgement signals indicate a successfully transmitted subset of IP packets. The successfully transmitted subset of IP packets are IP packets that have been positively acknowledged of being received, by the LTE network  106  to the wireless UE  104 . 
     At step  1018 , the LTE-MXC application processor  202  and the DSP  208  drop the successfully transmitted subset of IP packets based on the received acknowledgement signals. The LTE-MXC application processor  202  drops the successfully transmitted subset of IP packets by deleting the successfully transmitted subset of IP packets from the buffer. The DSP  208  drops the successfully transmitted subset IP packets by deleting the successfully transmitted subset IP packets from the local buffer present in the DSP  208 . 
     At step  1102 , the wireless UE  104  determines whether the handover of the wireless UE  104  from the LTE network  106  to the RAN  108  is complete. The handover is complete when the MMd_RRC module  214  establishes a wireless connection between the wireless UE  104  and the RAN  108 . 
     At step  1104 , the LTE processor  206  sends messages to the DSP  208  and the LTE-MXC application processor  202  when the handover is complete. The messages include the transmission status of the set of IP packets received by the LTE processor  206 . In one example, the transmission status indicates a subset of IP packets that were not successfully transmitted to the LTE network  106 , i.e., the subset of IP packets includes IP packets that have not been positively acknowledged of being received, by LTE network  106  to the wireless UE  104 . The subset of IP packets also includes IP packets buffered by the LTE processor  206  but could not be transmitted by the LTE processor  206  due to the handover. 
     At step  1106 , the DSP  208  transmits the subset of IP packets to the RAN  108  via the wireless connection between the wireless UE  104  and the RAN  108 . The subset of IP packets is determined by the transmission status the DSP  208  received from the LTE processor  206 . The method is completed after step  1106 . 
     In an example, the wireless UE  104  is used by a user in a car. The wireless UE  104  is connected to the LTE network  106  via a wireless connection. The wireless UE  104  transmits IP packets to the LTE network  106  via the wireless connection. As the car moves away from the LTE network  106  towards the RAN  108 , the signal strength the wireless UE  104  receives from the LTE network  106  weakens. Due to the weak signal strength some of the IP packets transmitted over the wireless connection may get lost. Thus the wireless UE  104  starts buffering the IP packets when the signal strength is lower than the pre-defined threshold. Further, as the car continues moving towards the RAN  108 , a handover is initiated to connect the wireless UE  104  to the RAN  108  so that the user does not experience an interruption in the communication process. On establishing a wireless connection between the wireless UE  104  and the RAN  108 , the wireless UE  104  retransmits those IP packets that were either not transmitted to the LTE network  106  or were lost during their transmission to the LTE network  106 . 
     While various embodiments of the present invention have been illustrated and described, it will be clear that the present invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the present invention, as described in the claims.

Metadata:
Filing Date: 20170324
Publication Date: 20180731
Grant Date: 20180731
Priority Date: 20080313
Inventors: TANEJA, MUKESH
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W36/023", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W36/14", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W84/042", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/023", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/1443", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W36/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W76/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W84/042", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/023", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/1443", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 41062954