Abstract:
A method for providing IDLE mode multimedia broadcast multicast service (MBMS) continuity in a telecommunication network is provided. The method includes providing an MBMS of interest for a user equipment (UE) from a first cell in the telecommunication network, using an MBMS gateway, performing a cell re-selection measurement of at least a second cell using the UE, the second cell being a neighboring cell to the first cell, wherein the cell re-selection measurement comprises determining a configuration of the second cell to facilitate an MBMS and determining a signal strength matching a predetermined strength value, and selecting one of the first cell and the second cell using the UE, which is configured to facilitate the MBMS and has a signal strength value at least equal to the predetermined strength value and greater than the other cell.

Description:
PRIORITY 
     This application claims priority under 35 U.S.C. § 119(a) to Indian Patent Application Serial No. 4448/CHE/2014, which was filed in the Indian Intellectual Property Office on Sep. 11, 2014, the entire disclosure of which is incorporated herein by reference. 
     BACKGROUND 
     1. Field of the Disclosure 
     The present disclosure relates generally to the field of telecommunication networks, and more particularly, to service-based prioritization of cells for improving IDLE mode multimedia broadcast multicast services (MBMS) service continuity in telecommunication networks. 
     2. Description of the Related Art 
     MBMS is a point-multi point specification for 3GPP cellular networks, which is designed to provide efficient delivery of broadcast and multicast services, both within a cell as well as within the core network. MBMS relies on Single Frequency Network configurations for the purpose of broadcast transmissions, wherein multiple cells, which are time synchronized, transmit the same contents over the same channel. 
     In the case of heterogeneous networks where a macro-pico structure is used, certain cells under any frequency layer are not configured to provide MBMS services. The network provides a user equipment (UE) connected to the network with information of the MBMS frequencies, the services provided by the frequencies (MBMS capabilities) using broadcast information and so on. Upon receiving this information, the UE prioritizes the frequency that provides the service(s) of interest to the user as the frequency of interest. This frequency of interest shall be used by the UE as the highest priority frequency in IDLE mode for a cell reselection procedure. However, not all cells under the frequency are configured to provide the service(s) of interest to the user. The existing prioritization techniques perform prioritization at the frequency level, and not at the cell level. As a result the UE is unaware of services being offered by each cell under the frequency layer being considered until the UE reselects the cell and reads the broadcast information. 
     As a result, the UE might end up in cells of the frequency of interest, which do not provide the service(s) the UE intends to receive. Further, the existing reselection rules do not offer any means for the UE to switch to another cell that provides the interested service. As a result, the UE will not be able to access the service, which, in turn, affects the user experience. 
     SUMMARY 
     The present disclosure has been designed to address at least the problems and/or disadvantages described above and to provide at least the advantages described below. 
     According to an aspect of the present disclosure, a method for providing IDLE mode MBMS continuity in a telecommunication network is provided. The method includes providing an MBMS of interest for a UE from a first cell in the telecommunication network, using an MBMS gateway, performing a cell re-selection measurement of at least a second cell using the UE, the second cell being a neighboring cell to the first cell, wherein the cell re-selection measurement comprises determining a configuration of the second cell to facilitate an MBMS and determining a signal strength matching a predetermined strength value, and selecting one of the first cell and the second cell using the UE, which is at least configured to facilitate the MBMS and has a signal strength value at least equal to the predetermined strength value and greater than the other cell. 
     According to another aspect of the present disclosure, system for providing IDLE mode MBMS service continuity in a telecommunication network is provided. The system is configured to provide an MBMS of interest for a UE from a first cell in the telecommunication network, using the UE, perform a cell re-selection measurement of at least a second cell using the UE, the second cell being a neighboring cell to the first cell, wherein the cell re-selection measurement includes determining a configuration of the second cell to facilitate an MBMS and determining a signal strength matching a predetermined strength value, and select one of the first cell and the second cell using the UE, which is at least configured to facilitate the MBMS and has a signal strength value at least equal to the predetermined strength value. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a block diagram illustrating an MBMS provisioning system, according to an embodiment of the present disclosure; 
         FIG. 2  is a block diagram illustrating components of an MBMS enabled UE, according to an embodiment of the present disclosure; 
         FIG. 3  is a flowchart illustrating a method of providing MBMS continuity using the MBMS provisioning system, according to an embodiment of the present disclosure; 
         FIG. 4  is a flowchart illustrating a method of reselecting from a non-MBMS cell to an MBMS cell by means of cell specific offset, using the MBMS provisioning system, according to an embodiment of the present disclosure; 
         FIG. 5  is a flowchart illustrating a method of barring a non-MBMS cell after performing cell reselection, using the MBMS provisioning system, according to an embodiment of the present disclosure; 
         FIG. 6  is a flowchart illustrating a method of barring a non-MBMS cell directly, without performing cell reselection, using the MBMS provisioning system, according to an embodiment of the present disclosure; and 
         FIG. 7  is a flowchart illustrating a method of removing applied cell specific restrictions, according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The same reference numbers are used throughout the drawings to refer to the same or like parts. Additionally, detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present disclosure. 
     Accordingly, examples provided herein should not be construed as limiting the scope of the embodiments herein. The term “cell” used in the following description refers to a sector being served by the eNodeB. One eNodeB can serve multiple cells. 
     The embodiments herein disclosed relate to a method and system for providing MBMS continuity in a telecommunication network. 
     Referring now to the drawings, and more particularly to  FIGS. 1-7 , where similar reference characters denote corresponding features consistently throughout the figures, there are shown several embodiments. 
       FIG. 1  is a block diagram illustrating an MBMS provisioning system  100 , according to an embodiment of the present disclosure. The MBMS provisioning system  100  includes an MBMS network  101  and at least one UE  106 . The MBMS network  101  includes a mobility management entity (MME)  102 , a multicast coordination entity (MCE)  103 , at least one eNodeB  104 , and an MBMS gateway  105 . 
     The UE  106  is configured to communicate with the eNodeB  104  to access the MBMS network  101 . The MCE  103  is configured to communicate with the eNodeB  104  and the MME  102  to manage resources and contents of various MBMS services being offered by the MBMS network  101 . The MME  102  is configured to act as a key control node and is responsible for managing and controlling IDLE mode operation of the UE  106 . The MME  102  is further responsible for authenticating the any resource/service access attempts of the UE  106 . 
     The MBMS gateway  105  is configured to manage and control multicast process for distributing MBMS user plane data. The MBMS gateway  105  is responsible for performing MBMS session control signaling through the MME  102 . The MBMS gateway  105  is further configured to provide MBMS service continuity between the MBMS network  101  and the UE  106 . The MBMS gateway  105  is also configured to provide at least one means for applying cell reselection rules for ensuring the MBMS service continuity. The MBMS gateway  105  is also configured to provide means for applying cell restrictions on non-MBMS cell(s). 
       FIG. 2  is a block diagram illustrating components of an MBMS enabled UE, according to an embodiment of the present disclosure. The MBMS enabled UE  106  includes a network (NW) interface module  201 , an MBMS application layer interface module  202 , a reselection module  203 , a memory module  204 , and a cell restriction module  205 . 
     The NW interface module  201  is configured to provide a means for connecting, using a suitable communication channel, the MBMS gateway  105  to the UE  106  through the eNodeB  104 . The NW interface module  201  is further configured to provide suitable means for the MBMS gateway  105  to collect all inputs required for the purpose of providing MBMS data continuity. For example, the NW interface module  201  communicates with the network and receives the information regarding barring time to apply for non-MBMS cells. 
     The MBMS Application Layer interface module  202  is configured to communicate with third party service providers, which offer different types of MBMS services to the UE  106 . The MBMS Application Layer interface module  202  is further configured to perform an authentication check of the third party service providers, which connect with the MBMS network  101 . The MBMS Application Layer interface module  202  is also configured to perform pre-processing of data received from the associated third party vendors, if required. 
     The reselection module  203  is configured to perform cell reselection measurement, wherein the reselection module  203  determines signal strength of the cell being considered. The reselection module  203  is further configured to determine configuration of the cell to facilitate MBMS. The reselection module  203  is also configured to determine whether the measured signal strength matches a predetermined strength value, wherein the predetermined strength value is a threshold value. 
     The memory module  204  is configured to store any data associated with the process of ensuring MBMS service continuity. For example, the memory module  204  stores information related to a predetermined strength value pertaining to signal strength. The memory module  204  also stores information related to type of MBMS service(s) that each UE  106  has subscribed for. The memory module  204  is further configured to store data required for performing authentication check of the UE  106 , as well as the service providers. 
     The cell restriction module  205  is configured to apply selected restriction(s) to selected cell(s). For example, the cell restriction module  205  is used to perform cell specific barring on selected cell(s). The cell restriction module  205  can bar a selected cell for a selected/preconfigured time period. The cell restriction module  205  can also bar a selected cell until an expiration of the current session. 
       FIG. 3  is a flowchart illustrating a method  300  of providing MBMS continuity using the MBMS provisioning system, according to an embodiment of the present disclosure. The MBMS network  101  provides, at step  302 , an MBMS of interest to the UE  106 , from a first cell that is configured to provide the MBMS of interest and a signal strength that at least matches a pre-determined strength value. 
     While receiving the MBMS from the first cell, the UE  106  performs, at step  304 , cell reselection measurement towards a second cell, wherein the second cell is a neighboring cell of the first cell, while the UE  106  initiates cell reselection measurement based on signal strength of the second cell. The term “MBMS capability” used henceforth refers to capability of the second cell to provide the MBMS of interest to the UE  106 . 
     During the cell reselection, if the second cell is found to have MBMS capability, then the reselection module  203  checks, at step  308 , whether the second cell provides the MBMS of interest. If the second cell is providing the MBMS of interest and if the signal strength of the second cell is more than that of the first cell, then the UE  106  reselects, at step  312 , to the second cell, and the MBMS gateway  105  provides the MBMS of interest through the second cell. 
     In accordance with another embodiment of present disclosure, the UE  106  can switch to the second cell if the signal strength provided by the second cell is higher than that of the first cell. If the second cell is not providing MBMS or the MBMS service of interest to the user, then the UE  106  switches back to the first cell. 
     In accordance with another embodiment of the present disclosure, instead of switching back to the first cell, the UE  106  can, with or without the assistance of the reselection module  203 , scan any of the neighboring cells, select a cell that matches requirements in terms of signal strength and MBMS capability, and then switch to the selected cell. 
     If the second cell is not providing MBMS, the MBMS enabled UE  106  applies, at step  310 , at least one selected solution to that cell. Alternatively, the MBMS enabled UE  106  can apply the solution(s) if the second cell is providing MBMS, however, not the MBMS of interest. For example, by applying a first solution, the MBMS enabled UE  106  reselects back to the first cell, from the second cell that does not provide MBMS/MBMS of interest. The various actions in the method  300  illustrated in  FIG. 3  can be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 3  may be omitted. 
       FIG. 4  is a flowchart illustrating a method  400  of reselecting from a non-MBMS cell to an MBMS cell by means of cell specific offset using the MBMS provisioning system, according to an embodiment of the present disclosure. The MBMS enabled UE  106  can use this method as a first solution upon identifying that the current cell (i.e. the second cell) the UE  106  is connected to is not providing an MBMS, or an MBMS of interest. 
     Upon identifying that the current cell (i.e. the second cell) that the UE  106  is connected to is not providing the MBMS, or the MBMS of interest, the reselection module  203  decides to switch back to the previous cell i.e. the first cell. To switch back to the first cell, the reselection module  203  adds, at step  402 , a cell specific offset towards the first cell. In another embodiment, the offset shall be applied towards the second cell instead of the first cell. In an embodiment, the UE  106 , based on data stored in the memory module  204 , selects the cell specific offset. In another embodiment, the cell specific offset can be selected by the eNB  104 . Further, by performing the cell reselection measurement and subsequent cell reselection, the UE  106  is switched, at step  406 , to the first cell, through which the MBMS gateway  105  provides the MBMS of interest to the UE  106 . The various actions in the method  400  illustrated in  FIG. 4  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 4  may be omitted. 
       FIG. 5  is a flowchart illustrating a method  500  of barring a non-MBMS cell after performing cell reselection, using the MBMS provisioning system, according to an embodiment of the present disclosure. The MBMS enabled UE  106  can use this method as a second solution upon identifying that the current cell (i.e. the second cell) the UE  106  is connected to is not providing an MBMS, or an MBMS of interest. 
     The MBMS enabled UE  106 , upon identifying that the second cell the UE  106  is connected to is not providing the MBMS, or the MBMS of interest, adds, at step  502 , a cell specific offset towards the first cell which has a configuration that matches requirements in terms of signal strength and MBMS capability. In another embodiment, the offset shall be applied towards a second cell instead of the first cell. Further, by performing cell reselection measurement towards the first cell, the UE  106  switches to the first cell, and the MBMS gateway  105  provides the MBMS of interest to the UE  106  through the first cell. Further, to prevent further cell reselection measurement towards the second cell that does not provide MBMS/the MBMS of interest, the UE  106  applies a suitable cell barring mechanism, and bars, at step  506 , the second cell. In various embodiments, the cell can be barred for a selected time period, or until the end of the current MBMS session. The various actions in the method  500  illustrated in  FIG. 5  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 5  may be omitted. 
       FIG. 6  is a flowchart illustrating a method  600  of directly barring a non-MBMS cell or cell not supporting the MBMS of interest (i.e. a second cell); immediately after reselecting to second cell using the MBMS provisioning system, according to an embodiment of the present disclosure. The MBMS enabled UE  106  shall subsequently return to previously camped cell immediately without completing the reselection procedure to second cell. The MBMS enabled UE  106  can use this method as a third solution upon identifying that the current cell (i.e. the second cell) the UE  106  is trying to reselect to is not providing an MBMS, or an MBMS of interest. 
     In this method, upon identifying that the second cell does not provide the MBMS, or the MBMS of interest, the MBMS UE  106  considers, at step  602 , the second cell to be barred. Further, without completing a cell reselection procedure towards the second cell, the UE  106  is immediately switched, at step  604 , back to the previous cell i.e. the first cell, which had been providing the MBMS of interest service to the UE  106 , before switching to the second cell. 
     Further, the UE  106  applies, at step  606 , cell specific restriction(s) to the second cell. For example, the cell specific restriction can refer to barring the second cell using a suitable cell barring mechanism. In various embodiments, the cell can be barred for a selected time period, or until the end of the current MBMS session. The various actions in method  600  illustrated in  FIG. 6  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 6  may be omitted. 
       FIG. 7  is a flowchart illustrating a method  700  of removing applied cell specific restrictions, according to an embodiment of the present disclosure. Consider that the UE  106  has applied, at step  702 , cell specific restriction(s) (which can be an offset, or barring) across frequencies. The UE  106  compares, at step  704 , the signal strength of the cell currently serving the UE  106  with MBMS with a minimum level of signal strength (as defined in the system information). If the signal strength of the cell currently serving the UE  106  is less than the minimum level of signal strength, the UE  106  removes, at step  706 , cell specific restriction(s) (which can be an offset, or barring) across frequencies towards cells, which do not provide non-MBMS. The UE  106  removes the restrictions immediately. The various actions in method  700  illustrated in  FIG. 7  may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in  FIG. 7  may be omitted. 
     The embodiments disclosed herein can be implemented through at least one software program running on at least one hardware device and performing network management functions to control the elements. The elements shown in  FIG. 1  can be at least one of a hardware device, or a combination of hardware device and software module. 
     It should be understood that the embodiments described herein are to be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. 
     While one or more embodiments of the present disclosure have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims and their equivalents.