DESCRIPTION
FIELD OF THE INVENTION
The invention relates in general to value added services provided to users of telecommunication network, and in particular, to a method and system for providing interactive cell broadcast messages to mobile terminals connected through the telecommunication network.
ACRONYMS
CBC - Cell broadcast Centre
CBS - Cell Broadcast Service
CBE- Cell Broadcast Entity
BBS - Base Station System
BSC - Base Station Controller
BTS - Base Transceiver Station
SCMI - Subscribed Cell broadcast service Message Identifier
CBMID - Cell Broadcast Message Identifier
ICMI - Interactive Cell broadcast service Message Identifier
CBMIR - Cell Broadcast Message Interactive Response
USSD - Unstructured Supplementary Service Data
WAP - Wireless application Protocol
VAS - Value Added Service
SMS - Short Message Service
BACKGROUND
Telecommunication service providers collaborate with value added service providers to provide VAS to the users of the telecommunication service. Examples of VAS include Short Message Service (SMS), Ring Back Tone (RBT) and Cell Broadcast Service (CBS).
SMS is a point-to-point (PTP) service i.e. by using SMS, a message may be sent from one mobile terminal in a telecommunication network to another

mobile terminal at a time. On tiie other liand, CBS is a point-to-multi-point (PTMP) or a point-to-area (PTA) service in which a message can be broadcasted by a network operator to all the mobile terminals in a certain geographic area at one time.
The cell broadcast service enables a message to be sent to all the mobile lerminals located in a specific geographical area, simultaneously. Hence, it has been found to be useful in warning people of a specific area during emergency situations like tsunami. The cell broadcast service is also useful in providing news alerts, stock updates and location based advertising information. Users of mobile terminals may subscribe to the cell broadcast service of receiving news alerts, stock updates or location based advertising information.
The cell broadcast services may also be interactive, requiring user of the mobile terminal to give a response in some specific manner after receiving a cell broadcast message. The response may be given for example by sending an SMS, by pressing a key on the keypad on the mobile terminal, selecting a menu item from a displayed menu, entering a text in a text box etc. In existing art, interaction information about the kind of response expected from the user is embedded in payload of the cell broadcast message and is displayed with the contents. The user reads the information from the displayed contents and responds according to the mentioned response manner.
A cell broadcast message can carry fixed number of characters in the payload. Embedding the interaction information in the payload consumes characters designated for actual information which needs to be communicated and hence may result in limitation on size of the content to be dispatched in the payload. This may also affect the throughput of the cell broadcast message during its transmission.
Hence, there is a need of a method for composing the cell broadcast message in an efficient manner so as to comprise the interaction information without compromising on the throughput and space available for content in the payload.

BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram depicting the environment of Cell Broadcast System in accordance with an embodiment of the invention;
FIG. 2 is block diagram depicting system configurations inside a mobile terminal, in accordance with an embodiment of the invention;
FIG. 3 is a flow chart representing a method of providing an interactive cell broadcast message to a mobile terminal, in accordance with an embodiment of the invention; and
FIG. 4 is a flow chart representing a method for analyzing a cell broadcast message received at a mobile terminal, in accordance with an embodiment of the invention.
FIG. 5 is a flow chart representing a method for analyzing a cell broadcast message received at a mobile terminal, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
In the following description, specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to a person ordinarily skilled in the art, that the invention may be practiced without these specific details. Various aspects and features of example embodiments of the invention are described in detail hereinafter.
The present invention discloses a method and a system for providing interactive cell broadcast service. Interactive cell broadcast service is a value added service which comprises sending cell broadcast messages with interactive content. The interactive content enables interaction between a user receiving the cell broadcast message and value added service provider. The interactive cell broadcast services send cell broadcast messages to which a user response is expected. The response may be in form of an sending a SMS, sending an USSD message, making a voice/video call, opening web browser, or pressing of keys on the user's mobile terminal. Keys may be pressed on the mobile phone to

select a menu item from a menu. The response may also be in the form of entering text in a text box.
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. FIG. 1 is a block diagram depicting the environment for Cell Broadcast System, in accordance with an embodiment of the invention.
The environment of the invention comprises cell broadcast entity, CBE 102; cell broadcast centre, CBC 104; a plurality of base station system BSS 106s; and a plurality of Mobile terminal 112s.
CBE 102 is an entity which creates cell broadcast messages. Thus, CBE 102 is a composing unit which composes cell broadcast messages. According to an embodiment, CBE 102 may interface with an application for creating the cell broadcast message. According to another embodiment, the application may be present with CBE 102 for creating cell broadcast. Each cell broadcast message may be between 1 to 15 pages in length. Each page may have 93 alphanumeric characters or 82 octets. Further, each CB message has a header and a payload. The step of composing a cell broadcast message has been explained in greater detail in conjunction with FIG 3. CBC 102 sends the cell broadcast message to CBC 104.
CBC 104 receives the cell broadcast message from CBE 102. Each cell broadcast message which is transmitted has to comply with GSM standards or according to the specifications provided by the manufacturer of base station controller, BSC 108. CBC 104 organizes the cell broadcast message received from CBE 102 according to the GSM standards. CBC 104. Further, CBC 104 determines the rate at which cell broadcast messages must be delivered and the geographical area where the cell broadcast message is to be transmitted. CBC 104 sends the cell broadcast message to BSS 106.
BSS 106 comprises of a base station controller, BSC 108 and a plurality of base transceiver stations, BTS 110. BSS 106 is responsible for broadcasting cell

broadcast messages to all Mobile terminal 112s located within the coverage area of BSS 106. Coverage area of BSS 106 represents physical area within which a transmission sent by BSS 106 can be received by a device capable of receiving the transmission, such as a mobile phone. BSC 108 receives the cell broadcast message from CBC 104 and routes it to specific BTS 110s depending upon the geographic area or cell in which the cell broadcast message has to be broadcasted. Thereafter, BTS 110s broadcasts the cell broadcast message to all Mobile terminal 112s located in its cell.
BSS 106 further receives transmissions from Mobile terminal 112s located within its coverage area and fonA/ards the transmission to its destination.
Mobile terminal 112 receives transmissions from BSS 106. For cell broadcast messages, Mobile terminal 112 take appropriate action, for example: action to display the cell broadcast message or discard the cell broadcast message. The configuration inside the mobile terminal is described in detail in conjunction with FIG. 2.
FIG. 2 is block diagram depicting system configurations inside Mobile terminal 112, in accordance with an embodiment of the invention.
Mobile terminal 112 comprises a receiver 202, a decision unit 204, a Client Module 206, a display unit 208 and a transmitter 210.
Receiver 202 is responsible for receiving transmissions from BSS 106. The transmissions may be a SMS, a call, a cell broadcast message and the like.
Decision unit 204 is responsible for taking decisions regarding cell broadcast messages received at receiver 202. The decisions may include displaying a cell broadcast message on display unit 208 or discarding the cell broadcast message. Logic behind the decisions is described in detail in conjunction with FIG. 4
Client Module 206 stores CBS information; CBS information comprises data related to cell broadcasting services to which user of mobile terminal 112 has subscribed. When the user subscribes to a cell broadcast service, he receives an acknowledgement from CBE 102 regarding confirmation of his subscription. Data regarding the cell broadcast service may accompany the

acknowledgement and get stored in Client Module 206. The acknowledgement may be in the form of a cell broadcast message, a SMS, a WAP message a USSD message and the like. The data comprises message parameters. In an embodiment of the invention, message parameters are message identifiers. In another embodiment of the invention, message parameters are sequence numbers. In another embodiment of the invention message parameter may be any other parameter in the header of a cell broadcast message. Message identifiers and sequence numbers are codes representing channels for each of the cell broadcast service.
Each cell broadcast service may have a unique message identifier. In an embodiment of the invention, cell broadcast messages associated with a cell broadcast service may comprise its message identifier. For example, a cell broadcast service for weather update may have message identifier 45000, and hence cell broadcast message associated with this cell broadcasts service will have 45000 in its body. Message identifiers for subscribed cell broadcast services may be may be stored in a Subscribed Cell broadcast service Message Identifier file or a SCMI file in client module 206. Example of SCMI file includes without limitation Cell Broadcast Message Identifier or CBMID file. The CBMID is a standard GSM file which is stored in the subscriber identity module (SIM) card in mobile terminal 112.
In another embodiment of the invention, each cell broadcast service may have a unique sequence number. Cell broadcast messages associated with a cell broadcast service may comprise its sequence number. Sequence numbers for subscribed cell broadcast services may be stored in a sequence number (SN) file. The SN file is stored in client module 206.
CBS information further comprises data regarding interactive cell broadcast services. The interactive cell broadcast messages may be differentiated based on the kind of response expected from the user. There may be One Key (OK) Message Services, Multi Keys (MK) Message Services or Display Message Services. Response to an OK message service may be given by pressing one key on mobile terminal 112; for example by pressing '*' key.

Response to a MK message service may be given by pressing more than one key on mobile terminal 112; for example by writing a word or sentence or by pressing a series of l^eys. Display message service does not expect a response and are only for display purposes. Further, on pressing the one key or multi-key, an SMS may be sent to BSS 106 by client module 206 from where the response is received by the VAS provider providing the cell broadcast message service.
CBS information further comprises message parameters representing ranges for the interactive cell broadcast services. In an embodiment of the invention, CBS information comprises message identifiers for the interactive cell broadcast services. The message identifiers for the interactive cell broadcast services are stored in an Interactive Cell broadcast service IVIessage Identifier file or an ICMI file stored in client module 206. Example of an ICMI file includes without limitation a CBMIR file. A CBMIR file is a standard GSM file stored in the SIM card of mobile terminal 112. ICMI comprises message identifier ranges for OK message services, MK Message services and display message services. For example, a range of 41000 - 42000 may be reserved for OK message services; a range of 42000 - 43000 may be reserved for MK message services; a range of 43000 - 44000 may be reserved for display message services. Therefore a cell broadcast message having a message identifier as 41050 will be identified as cell broadcast message with one key response.
In another embodiment of the invention, CBS information comprises sequence numbers representing ranges for the interactive cell broadcast services stored in the SN file in client module 206.
Each service like OK, MK and display has a predefined channel range. Cell broadcast messages corresponding to OK service are sent on channels predefined for the OK service; cell broadcast messages corresponding to MK service are sent on channels predefined for the MK service; and cell broadcast messages corresponding to display service are sent on channels predefined for the display service. Each channel is associated with a message parameter. The message parameter is stored in client module 206.

Client module 206 stores the association between the message parameters and the response action corresponding to the message parameter. Response action includes response parameter and destination information. For previous example, response parameter will represent which key needs to be pressed to carry out the response action. For example, consider the given OK message service: Press key representing each song to make the song your RBT:
1) Song A
2) SongB
3) SongC
4) SongD
5) SongE
Here, either of key 1, 2, 3, 4 or 5 is to be pressed as correct response action. Response parameter will comprise the information about the correct response action.
The destination information describes where the response would be sent by client module 206 corresponding to the different kinds of interactive cell broadcast services.
Following table shows an illustration of the association between message identifier, response parameters and destination information.

Thus, response action to a cell broadcast message with message identifier 41050 is defined as pressing of '#' key and the response being sent to the destination 5888. Similarly for a cell broadcast message with message identifier as 41150, a response action is not required.

In another embodiment of the invention, as association between sequence numbers, response parameters and destination information is stored in client module 206.
Further, Client Module 206 also stores message parameters and response information for USSD messages, WAP messages and other interactive services.
Display unit 208 displays contents for the user on mobile terminal 112. This may include displaying SMS, cell broadcast messages, GUI for games, setting, menu browsing etc.
Transmitter 210 is responsible for any transmission made by mobile terminal 112. The transmissions may include a call to other mobile terminal, sending an SMS, sending response to a cell broadcast message and the like.
FIG. 3 is a flow chart representing a method of providing an interactive cell broadcast message to Mobile terminal 112, in accordance with an embodiment of the invention.
Interactive cell broadcast message is a cell broadcast message with interactive content. The interactive content enables interaction between a user receiving the cell broadcast message and value added service provider.
At step 302, a message parameter is selected by CBE 102. The message parameter belongs to a range representing interactive cell broadcast services. The range is defined beforehand by CBE 102 and communicated to mobile terminal 112. The communication may be through an SMS, a cell broadcast, WAP, and GPRS etc. Hence Mobile terminal 112 has information about message identifiers of interactive cell broadcast services provided by CBE 102.
At step 304, the message parameter is embedded in header of a cell broadcast message by CBE 102. In existing art, response information of an interactive cell broadcast message is sent as part of payload of the cell broadcast message. The response information comprises data about kind of interactive cell broadcast message and destination information for sending the response action.
The response information consumes unnecessary space in the payload which is meant for carrying displayable content which is message or update or news which needs to be communicated to user. Hence presence of response

information limits size of tlie displayable content which can be dispatched in the payload.
The present invention solves this problem by using a suitable message parameter in the header of the cell broadcast message. The message parameter corresponds to predefined response information, specifying the response initiated from mobile terminal 112 of the user. In an embodiment of the invention, message identifier is used as the message parameter. The information of the message identifier and the predefined response initiated from Mobile terminal 112 of the user is stored in ICMI file. In another embodiment of the invention, sequence number is used as the message parameter. The information of the sequence number and the predefined response initiated from mobile terminal 112 of the user is stored in the SN file. Hence the payload is available for the displayable content. Using the message parameter in the header associated with a response information, enables better usage of space available in payload of the cell broadcast message and results in the better utilization of the throughput available for the cell broadcast service.
Thus, the response information is available with Mobile terminal 112 beforehand. Hence the present invention requires only the message parameter to be sent in the cell broadcast message, saving space in payload which in existing art is consumed by the response information.
At step 306, CBE 102 embeds the displayable content in payload of the cell broadcast message. The displayable content is the actual message or update which has to be communicated to subscribers of the selected cell broadcast services. Thereafter composition of the cell broadcast message is completed.
At step 308, the cell broadcast message is transmitted to a mobile terminal 112. The transmission involves a series of transmission starting with CBE 102. CBE 102 transmits the cell broadcast message to CBC 104. CBC 104 transmits the cell broadcast message to a plurality of BSS 106s. The plurality of BSS 106s then broadcasts the cell broadcast message to different Mobile terminal 112s situated within the coverage area of each BSS 106. Thus, CBC

104 along with the plurality of BSS 106s form transmitter unit for broadcasting the cell broadcast message.
At step 310, the cell broadcast message is received by receiver 202 of Mobile terminal 112. Receiver 202 forwards the cell broadcast message to decision unit 204.
At step 312, the cell broadcast message is analyzed by decision unit 204. The analysis process is described in detail in conjunction to FIG. 4 and FIG 5.
At step 314, after analysis, a response action is sent to BSS 106 based on the analysis of decision unit 204. According to an embodiment, the response action may be a transmission such as an SMS, a call and the like. The response action is sent by client module 206 based on the response of the user.
FIG. 4 is a flow chart representing a method for analyzing a cell broadcast message received at mobile terminal 112, in accordance with an embodiment of the invention.
At step 402, decision unit 204 reads the message identifier in the header of the cell broadcast message.
At step 404, decision unit 204 compares the message identifier with message identifiers stored in ICMI file in client module 206. The message identifiers in ICMI file represents ranges for different kinds of interactive cell broadcast services.
At step 406, decision unit 204 ensures if the message identifier from the cell broadcast message falls within any range defined by message identifiers stored in ICMI, for any interactive cell broadcast service. In case the message identifier does not fall within any range defined by message identifiers stored in ICMI, step 408 is executed.
In case, at step 406, the message identifier falls within any range defined by message identifiers stored in ICMI, step 410 is executed. At step 410, decision unit 204 extracts response information related to the message identifier of the cell broadcast message, from Client Module 206. For example, in case the message identifier is 41050, then according to table 1, decision unit 204 will

extract information that response action to the cell broadcast message is pressing of key '#' and the response action needs to be sent to 58888.
At step 412, decision unit 204 displays the displayable content of the cell broadcast message on display unit 208. The user after viewing the displayable content may decide to send or not send the response action. In case user decides to send the response action, he presses the required key and at step 414, the response action is sent to its destination by client module 206 using transmitter 210. For example, in the previous example, as the user presses the '#' key, the response action will be transmitted to 58888 by client module 206 using transmitter 210.
The response action will be received by BSS 106, in whose coverage area mobile terminal 112 is. BSS 106 will then forward the response action to destination, which is for previous example '58888'. Hence BSS 106 acts as receiver unit for receiving response actions from mobile terminal 112.
At step 408, decision unit 204 checks if the message identifier falls within any range specified in SCMI file. In case the message identifier falls within a range specified in SCMI, the cell broadcast message is displayed on display unit 208 at in step 416. In case, message identifier does not fall within a range specified in SCMI, client module 206 rejects the cell broadcast message and hence does not display it on display unit 208.
FIG. 5 is a flow chart representing a method for analyzing a cell broadcast message received at mobile terminal 112, in accordance with an embodiment of the invention.
At step 502, decision unit 204 reads the sequence number in the header of the cell broadcast message.
At step 504, decision unit 204 compares the sequence number with sequence numbers stored in the SN file in client module 206. The sequence numbers in the SN file represents ranges for different kinds of interactive cell broadcast services;
In case, at step 506, the sequence number falls within any range defined by sequence numbers stored in the SN file decision unit 204 extracts response

information related to tine sequence number of the cell broadcast message, from Client Module 206.
At step 508, decision unit 204 displays the displayable content of the cell broadcast message on display unit 208. The user after viewing the displayable content may decide to send or not send the response action. In case user decides to send the response action, he presses the required key and at step 510, the response action is sent to its destination by client module 206 using transmitter 210.
The response action will be received by BSS 106, in whose coverage area hriobile terminal 112 is. BSS 106 will then fon/vard the response action to destination. Hence BSS 106 acts as receiver unit for receiving response actions from mobile terminal 112.
It should be apparent to a person skilled in the art that system elements used in the invention are well known in the art; hence other known system elements could also be used in the invention for the same purpose without departing from the scope of the invention.
While examples embodiments of the invention have been illustrated and described, it will be clear that the 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 invention as described in the claims.

WE CLAIM:
1. A method of providing an interactive cell broadcast message to a mobile
terminal, the mobile terminal comprising a client module, the interactive
cell broadcast message comprising a header and a payload, the cell
broadcast message being transmitted over a telecommunication network,
the method comprising:
i) composing a cell broadcast message with a message parameter in the header of the cell broadcast message, the message parameter associated with a response action, the association between the message parameter and the response action being stored in the client module on the mobile terminal; ii) transmitting the cell broadcast message to the mobile terminal; and iii) on the mobile terminal, identifying the response action associated with the message parameter.
2. The method of claim 1, wherein the client module is an application in the mobile terminal.
3. The method of claim 1, wherein the client module is stored in subscriber identity module card in the mobile terminal.
4. The method of claim 1, wherein the message parameter is a message identifier.
5. The method of claim 1, wherein the message parameter is a sequence number.
6. A method of providing an interactive cell broadcast message to a mobile terminal, the mobile terminal comprising a client module, the interactive cell broadcast message comprising a header and a payload, the cell broadcast message being transmitted over a telecommunication network, the method comprising:
i) composing a cell broadcast message with a message parameter in the header of the cell broadcast message, the message parameter associated with a response action, the association between the

message parameter and the response action being stored in the
client module in the mobile terminal; ii) transmitting the cell broadcast message to the mobile terminal; and iii) on the mobile terminal, identifying the response action associated
with the message parameter; and iv) receiving the response action from the mobile terminal.
7. The method of claim 6, wherein the client module is an application in the mobile terminal.
8. The method of claim 6, wherein the client module is stored in subscriber identity module card in the mobile terminal.
9. The method of claim 6, wherein the message parameter is a message identifier.
10. The method of claim 6, wherein the message parameter is a sequence number.
11. A system for providing an interactive cell broadcast message, the cell broadcast message being transmitted over a telecommunication network, the system comprising:
i) A composing unit, the composing unit configured to compose the interactive cell broadcast message comprising a message parameter, the message parameter representing a response action; and ii) A transmitting unit, the transmitting unit configured to broadcast the interactive cell broadcast message over the telecommunication network. 12.The system of claim 11 further comprises a receiver unit configured to receive the response action from a mobile terminal, in response to the transmission of the cell broadcast message. 13.The system of claim 11, wherein the composing unit is a Cell Broadcast
Entity. 14.The system of claim 11, wherein the composing unit is an application interfaced with a Cell Broadcast Entity.

15. The system of claim 11, wherein the transmitting unit comprises of:
i) A Cell Broadcasting Centre; and
ii) A plurality of Base Station Systems.
16. The system of claim 12, wherein the mobile terminal comprises:
i) A receiver, the receiver configured to receive the cell broadcast
message; ii) A decision unit, the decision unit configured to:
a) analyze the cell broadcast message; and
b) decide a response action based on the analysis of the cell
broadcast message;
iii) A display unit, the display unit configured to display at least one part of the cell broadcast message based on the analysis; and
iv) A transmitter, the transmitter configured for sending a transmission corresponding to the response action, to the receiver unit.
17. The system of claim 16 further comprises a Client Module configured to
store logic for the response action.