Abstract:
Apparatus and method for multi-tasking in mobile terminal having multimedia processor for video-on-demand (VOD) services that identifies port of each data received during use of VOD service and processes data to enable user to implement any other network application program simultaneously with use of VOD service. Method provided includes setting port number for VOD services of multimedia processor and accessing VOD server when demand for VOD services is received, processing VOD data received through the set port number to deploy VOD services, determining whether port number of data received during VOD services is identical to the set port number. When the port number of the received data is identical to the set port number, recognizing received data as VOD data to deploy VOD services, when not, recognizing received data as general data and sending it to MSM from the multimedia processor, and processing general data sent to the MSM.

Description:
PRIORITY 
   This application claims priority under 35 U.S.C. §119(a) to an application entitled “Method of Multi-Tasking in Mobile Terminal” filed with the Korean Intellectual Property Office on Nov. 26, 2003 and assigned Serial No. 2003-84578, the entire contents of which are hereby incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a method of multi-tasking in a mobile terminal. More particularly, the present invention relates to a method of multi-tasking in a mobile terminal that identifies a port of each data received during the use of a video-on-demand (VOD) service and processes the data to enable a user to implement any other network application program simultaneously with the use of the VOD service. 
   2. Description of the Related Art 
   Due to the development of mobile communication technologies, mobile terminals have been widely supplied and developed to offer various services. Mobile terminals are available for a wide range of applications and are more integrated than pre-existing mobile phones to perform various additional functions. These functions include camera, camcorder and multimedia functions. 
   Multimedia can be defined as a combination of sound, text, graphics, moving images, and other types of information. The multimedia function enables users to receive VOD services on various multimedia contents, including image data (such as films and music videos), through a wireless network from multimedia servers. VOD services stream the multimedia contents in real-time. For more stable processing of multimedia data, it has been suggested to mount a multimedia chip in a mobile terminal 
   Mobile station modem (MSM) chips in mobile terminals serve as a modem for accessing wireless networks. Multimedia chips process multimedia data (hereinafter referred to as “VOD data”) received through the mobile terminal. 
   Conventional mobile terminals make the best use of wireless network access to speed up wireless network data processing and offer VOD services using a multimedia chip that serves as a multimedia data decoder for VOD. Conventional mobile terminals can accomplish this without lowering the wireless network data processing rate. 
   The conventional mobile terminal separates protocols for VOD services and processes all data received through a wireless network in the multimedia chip. Thus, while receiving VOD streaming services using the multimedia chip, it cannot implement any other network application program, such as a browser or game download, simultaneously. 
   SUMMARY OF THE INVENTION 
   Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a method of multi-tasking in a mobile terminal to enable a user to implement other network application programs simultaneously with the use of VOD services by analyzing port information of each data received during the use of VOD services and processing the data according to the port information. 
   In order to accomplish the above object of the present invention, there is provided a method of multi-tasking in a mobile terminal having a multimedia processor for VOD services, which comprises the steps of setting a port number for the VOD services of the multimedia processor and accessing a VOD server when demand for VOD services is received,; processing VOD data received through the set port number to deploy VOD services, determining whether a port number of data received during the VOD services is identical to the set port number and, in the affirmative, recognizing the received data as the VOD data to deploy the VOD services, and recognizing the received data as general data and sending the data to an MSM from the multimedia processor when the port number of the received data is not identical to the set port number. The method according to an embodiment of the present invention further comprises processing the general data sent to the MSM. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  is a view showing the structure of a multi-tasking mobile terminal according to an embodiment of the present invention; 
       FIG. 2  is a flow chart showing a process of multi-tasking in a mobile terminal according to an embodiment of the present invention; and 
       FIG. 3  is a view showing protocol stacks of the MSM and multimedia processor in  FIG. 1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein have been omitted for conciseness. 
   The mobile terminal which will be explained herein is a VOD terminal that supports VOD services. In addition, the term “general data” means all data other than VOD data, which is received through a wireless network. 
   It is assumed that VOD data and general data are both packet data. The mobile terminal according to an embodiment of the present invention implements multi-tasking by processing general data received through a wireless network during the use of VOD services. 
   For reasons of conciseness, an explanation of how to send data (signals requesting VOD playback, temporary stop, VOD data, etc.) to a VOD server from a multimedia processor will be omitted herein. 
     FIG. 1  shows the structure of a multi-tasking mobile terminal according to an embodiment of the present invention. 
   Referring to  FIG. 1 , an RF section  21  performs the wireless communication functions for the mobile terminal. The RF section  21  comprises an RF transmitter for performing upward conversion and amplification of the frequency of a signal that is transmitted, and an RF receiver for amplifying a signal that is received, with low noise and performing downward conversion of the frequency of the signal. 
   A data processor  23  comprises a transmitter for coding and modulating a signal that is transmitted and a receiver for demodulating and decoding a signal that is received. The data processor  23  can be composed of a modem and a codec. 
   An audio processor  25  reproduces an audio signal output from the data processor  23 , or transmits an audio signal generated from a microphone to the data processor  23 . The audio processor  25  also outputs an audio signal included in a real-time VOD data stream to the speaker. 
   A keypad  27  (not shown) is provided with keys for inputting numbers and characters and function keys for setting up various functions. The key input section  27  can also include a VOD access key, a menu key, a direction key and an OK key according to an embodiment of the present invention. 
   A memory  29  can be composed of a program memory and a data memory. The program memory stores programs for controlling general operations of the mobile terminal, programs for processing general data received during the processing of VOD data and a port number set to process the VOD data. The data memory temporarily stores data generated during implementation of the above programs. 
   A multimedia processor  31  processes VOD data received through a wireless network during VOD service. The multimedia processor  31  reads out the port number set in the memory  29  to determine whether any received data is VOD data or general data. When the received data is VOD data, the multimedia processor  31  processes the VOD data through decapsulation in a protocol stack from lower to higher layers. 
   Otherwise, when general data is received, the multimedia processor  31  encapsulates the data in the protocol stack from a transfer layer (TCP/UDP layer) to the lowest physical layer and transmits the encapsulated data to a control section (hereinafter referred to as mobile station modem (MSM))  10 . 
   The MSM  10  controls the overall operations of the mobile terminal. The MSM  10  sends general data received upon selection of a multi-tasking menu during a VOD service to the multimedia processor  31 . When the multimedia processor  31  determines that a port number of the general data is different from the port number set for VOD services, it inputs the general data again to the MSM  10 . The MSM  10  then processes the received general data through decapsulation up to the highest layer, i.e. the WAP layer. When an input from the VOD access key is detected (i.e., when the VOD access key is activated), the MSM  10  assigns a port number for VOD services and outputs the port number to the memory  29 . The MSM  10  controls overall operations to process VOD data through a VOD service. At the same time, the MSM  10  receives and processes general data returned from the multimedia processor  31  during use of the VOD service. 
   In addition, the MSM  10  performs multi-tasking by implementing an application program corresponding to the other general data upon selection of the multi-tasking menu during the VOD service. 
   A display section  40  displays messages generated during the implementation of a program under control of the MSM  10 . The display section  40  also displays user data output from the MSM  10 . In addition, the display section  40  displays VOD data output from the multimedia processor  31  and general data output from the MSM  10  simultaneously. The display section  40  can be an LCD comprising an LCD controller, a memory for storing image data and an LCD device. When the LCD is a touch screen, it can serve as an input means (i.e., the keypad  27 ). 
   Referring to  FIG. 1 , if a user (caller) sets an outgoing call mode after dialing using the keypad  27 , the MSM  10  will detect the mode and will process the dialing information received through the data processor  23 . The MSM  10  converts the dialing information into an RF signal and outputs the RF signal. A reply signal generated from a recipient is detected by the RF section  21  and the data processor  23 . The audio processor  25  then forms a voice communication path so that the user can communicate with the recipient. When detecting an incoming call, the MSM  10  controls the audio processor  25  to generate a ringing signal. When the user replies to the incoming call, the MSM  10  detects the reply and controls the audio processor  25  to form a voice communication path so that the user can receive the incoming call. Although voice communications in the incoming or outgoing call mode have been explained above, the MSM  10  can also perform data communications to receive or transmit packet data or image data. In a standby mode or a messaging mode, the MSM  10  displays text data processed by the data processor  23  on the display section  40 . 
   The mobile terminal processes data for multi-tasking to implement an application program corresponding to general data received through a wireless network during a VOD service. If a port number of data analyzed through decapsulation over the protocol layers of the multimedia processor  31  is different from the port number set during the use of the VOD service, the multimedia processor  31  will encapsulate the data down to the lowest protocol layer and will send the encapsulated data to the MSM  10 . At this time, the multimedia processor  31  will also send information indicating that the received data is not VOD but general data. 
   The MSM  10  decapsulates the received general data up to the highest protocol layer and processes the general data using a corresponding application program, thereby performing multi-tasking that simultaneously processes the VOD data at the multimedia processor  31  and the general data at the MSM  10 . 
     FIG. 2  is a flow chart illustrating the steps of a method for multi-tasking in a mobile terminal according to an embodiment of the present invention. 
   Referring to  FIG. 2 , the MSM  10  in the standby mode detects whether the VOD access key has been activated at decision step  211 . If the VOD access key has been activated (“Yes” path from decision step  211 ), the MSM  10  will proceed to step  212  to independently set a port number to be used for VOD services by the multimedia processor  31  and store the port number in the memory  29 . If the VOD access key has not been activated (“No” path from decision step  211 ), the MSM  10  performs the required function in step  221 . 
   At step  213 , the MSM  10  accesses a wireless network. At step  214 , the multimedia processor  31  processes VOD data received through the MSM  10  and displays the processed VOD data on the display section  40 . The protocol architectures of the MSM  10  and the multimedia processors  31  will be explained in detail with reference to  FIG. 3 . 
     FIG. 3 . shows protocol stacks of the MSM and multimedia processor in  FIG. 1 . 
   As shown in  FIG. 3 , MSM  10  protocol stack  302  is comprised of a lowest physical layer, an radio link protocol (RLP) layer, a point-to-point protocol (PPP) layer, an internet protocol (IP) (layer, a transmission control protocol/user datagram protocol (TCP/UDP) layer, a socket layer and a highest wireless application protocol (WAP) layer. 
   The MSM  10  having the above protocol stack  302  decapsulates received data in each protocol layer and passes the data on to an application program through the highest WAP layer. 
   Also shown in  FIG. 3  is a multimedia processor  31  protocol stack  304  that is comprised of an IP layer, a TCP/UDP layer, a socket layer and an RTP/RTCP/RTSP/HTTP layer. The multimedia processor  31  processes data received from the MSM  10  through a wireless network during use of a VOD service. 
   The MSM  10  connected to the VOD server through the physical layer processes received VOD data through the RLP and PPP layers and sends the VOD data to the multimedia processor  31 . This occurs in step  214 . Then the multimedia processor  31  processes the VOD data by passing the data on to the higher layers. 
   The VOD data is processed along the data processing path as explained above. The user can receive desired VOD data in real-time from the VOD server on a wireless network. While processing the received VOD data, the multimedia processor  31  determines, at decision step  215 , whether the port number of the received VOD data that has been analyzed at the TCP/UDP layers is identical to the preset port number. If the port number of the received VOD data is identical to the preset port number (“Yes” path from decision step  215 ), the multimedia processor  31  will recognize that the received data is VOD data and will keep on deploying VOD services at step  216 . 
   Otherwise, if the port number of the received data is not determined to be identical to the preset one at step  215  (“No” path from decision step  215 ), the multimedia processor  31  will encapsulate the general data (which has been decapsulated from the protocol layer lower than the TCP/UDP layer) conversely down to the lowest IP layer. 
   At step  218 , the multimedia processor  31  sends the encapsulated general data, as well as information indicating that the received data is not VOD but general data, to the PPP layer of the MSM  10  from its lowest IP layer. At step  219 , the MSM  10  decapsulates the received general data over its IP layer through WAP layer. At step  220 , the MSM  10  implements the general data. The multimedia processor  31  keeps on processing the VOD data to provide VOD services. 
   Steps  217  to  220  are general data processing steps for multi-tasking in the mobile terminal. When the user presses a menu key to select the multi-tasking menu in order to use another function through a wireless network during the use of a VOD service, the multimedia processor  31  processes general data corresponding to the other function using the multi-tasking function, thereby implementing the other function simultaneously with the VOD services. 
   Although  FIG. 3  illustrate specific protocol stacks of the MSM  10  and the multimedia processor  31 , other protocol stacks can be used in the MSM  10  and the multimedia processor  31 . For example, the multimedia processor  31  can have a PPP layer as the lowest layer in its protocol stack, while the other layers are the same as shown in  FIG. 3 . 
   In such case, however, the MSM  10  decapsulates received data down to the RLP layer. Also, upon receiving the data from the MSM  10 , the multimedia processor  31  decapsulates the data from the lowest PPP layer. 
   Display of the VOD data and general data on the display section  40  as a result of the multi-tasking function according to an embodiment of the present invention will be explained in detail. 
   When the user selects either VOD data for a VOD service or general data for another service or function, the selected service data is displayed as a main picture, while the other data is processed as a background. It is also possible to display the general data while processing the VOD data. To accomplish this, the display section  40  is divided into upper and lower parts. The general data and the VOD data can be displayed respectively at the upper and lower parts of the display section  40 , and vice versa. Accordingly, both data can be displayed simultaneously. Therefore, various methods are available to simultaneously display general data and VOD data processed through multi-tasking. 
   Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims, including the full scope of equivalents thereof.