Abstract:
Disclosed is an apparatus for enabling a user to selectively view satellite digital multimedia broadcasts or terrestrial digital multimedia broadcasts through a single terminal, a control method thereof, and a card for receiving the digital multimedia broadcasts. The apparatus includes a first card for receiving a terrestrial digital multimedia broadcast, a second card for receiving a satellite digital multimedia broadcast, and a terminal adapted to receive either card so as to receive a digital multimedia broadcast from the inserted card and to reproduce the digital multimedia broadcast. Each card includes a receiving unit for receiving and processing a digital multimedia broadcast signal, a memory for temporarily storing data from the digital multimedia broadcast signal, an interface unit for interfacing the card and a terminal for reproducing the digital multimedia broadcast when the card is inserted into the terminal, and a node for transmitting the data to the terminal.

Description:
PRIORITY  
       [0001]     This application claims the benefit under 35 U.S.C. 119(a) of an application entitled “Apparatus And Method For Reproducing Digital Multimedia Broadcast And Card Adaptable For Receiving Digital Multimedia Broadcast” filed in the Korean Intellectual Property Office on Feb. 7, 2005 and assigned Serial No. 2005-11251, the entire contents of which are incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to an apparatus and method for receiving and reproducing digital multimedia broadcasts, and more particularly to an apparatus for enabling a user to selectively view satellite digital multimedia broadcasts or terrestrial digital multimedia broadcasts through a single terminal, a control method thereof, and a card for receiving the digital multimedia broadcasts.  
         [0004]     2. Description of the Related Art  
         [0005]     Various terminals capable of receiving and reproducing digital multimedia broadcast (DMB) have been developed. Such terminals include a mobile equipment (ME) such as a portable wireless telephone, a personal digital assistant (PDA) that can receive and reproduce digital multimedia broadcasts, as well as terminals designed for digital multimedia broadcasts.  
         [0006]      FIG. 1  is a block diagram illustrating the structure of a conventional ME for receiving and reproducing digital multimedia broadcasts.  
         [0007]     Such equipment must include, at least, a radio frequency (RF) unit  52  for receiving digital multimedia broadcast, a demodulating unit  54 , a digital signal processor (DSP)  56 , a memory unit  60  and a controller  58  for controlling at least the units and processor.  
         [0008]     Satellite digital multimedia broadcast and terrestrial digital multimedia broadcast are broadcasted through different frequencies. Therefore, an ME capable of receiving satellite digital multimedia broadcast cannot receive terrestrial digital multimedia broadcast. Similarly, an ME capable of receiving terrestrial digital multimedia broadcast cannot receive satellite digital multimedia broadcast. Consequently, a user who desires to view both types of broadcasts must have two ME units, which causes the user to incur inconvenience and an economic burden.  
       SUMMARY OF THE INVENTION  
       [0009]     Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and provides an apparatus for enabling a user to selectively view satellite digital multimedia broadcasts or terrestrial digital multimedia broadcasts through a single terminal, a control method thereof, and a card for receiving the digital multimedia broadcasts.  
         [0010]     To this end, in accordance with a first aspect of the present invention, there is provided an apparatus for reproducing a digital multimedia broadcast, including two cards for receiving terrestrial and satellite digital multimedia broadcasts, respectively, and a terminal adapted to receive the either card so as to receive a digital multimedia broadcast from the inserted card and to reproduce the digital multimedia broadcast. That is, two types of cards including different RF units and demodulating units are configured, so that the user can view terrestrial and satellite digital multimedia broadcasts through a single terminal.  
         [0011]     In accordance with a second aspect of the present invention, there is provided a method for reproducing a digital multimedia broadcast in a terminal, into which a card for receiving the digital multimedia broadcast can be inserted, the method including sensing that the card is inserted and analyzing a transmission stream packet for a digital multimedia broadcast transmitted from the card, determining whether a signal to be received is a terrestrial digital multimedia broadcast signal or a satellite digital multimedia broadcast signal, based on a result of the analysis, and controlling a terrestrial or satellite digital multimedia broadcast, according to a result of the determination.  
         [0012]     In accordance with a third aspect of the present invention, there is provided a card for receiving a digital multimedia broadcast, the card including a receiving unit for receiving and processing a digital multimedia broadcast signal, a memory for temporarily storing data from the digital multimedia broadcast signal, an interface unit for interfacing the card and a terminal for reproducing the digital multimedia broadcast when the card is inserted into the terminal, and a node for transmitting the data to the terminal. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     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:  
         [0014]      FIG. 1  is a block diagram illustrating the structure of functional parts provided in a conventional ME for receiving and reproducing digital multimedia broadcasts;  
         [0015]      FIG. 2  is a block diagram illustrating the structures of a mobile equipment for reproducing digital multimedia broadcasts and two cards for receiving different digital multimedia broadcasts according to an embodiment of the present invention;  
         [0016]      FIG. 3  is a flowchart illustrating the procedure for processing satellite digital multimedia broadcast and terrestrial digital multimedia broadcast while distinguishing the satellite digital multimedia broadcast from terrestrial digital multimedia broadcast in the mobile equipment for reproducing the digital multimedia broadcast according to an embodiment of the present invention; and  
         [0017]      FIG. 4  is a block diagram illustrating the structures of a mobile equipment for reproducing digital multimedia broadcasts and two cards for receiving different digital multimedia broadcasts according to another embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]     Hereinafter, preferred embodiments according to the present invention will be described with reference to the accompanying drawings. It is to be noted that the same elements are indicated with the same reference numerals throughout the drawings. In the below description, many particular items, such as a detailed node name and a header value, are provided for promoting a general understanding of the present invention. However, it will be understood by those skilled in the art that the present invention can be embodied without including these particular items. A detailed description of known functions and configurations incorporated herein will be omitted for the sake of clarity.  
         [0019]     According to the present invention, a receiving section and a reproducing section are mechanically separated in order for a user to selectively view satellite digital multimedia broadcast and terrestrial digital multimedia broadcast. That is, the receiving section is configured with a satellite digital multimedia broadcast-based memory card and a terrestrial digital multimedia broadcast-based memory card, both of which can connect to or disconnect from the ME having the reproducing section. The two types of cards include a logic module consisting of a radio frequency unit and a baseband processing/demodulating unit, which are provided in the conventional ME. Since a digital signal processing unit (DSP) for the satellite digital multimedia broadcast and terrestrial digital multimedia broadcast can be shared, the DSP is included inside of the ME. In other words, the DSP includes software for decoding both a satellite digital signal and a terrestrial digital signal.  
         [0020]      FIG. 2  is a block diagram illustrating the structures of a ME for reproducing digital multimedia broadcasts and two cards having different RF and baseband processing units for receiving different digital multimedia broadcasts, according to an embodiment of the present invention. The user can view a desired broadcast by inserting the appropriate card into the ME.  
         [0021]     The ME for reproducing digital multimedia broadcasts may be a dedicated terminal or a multi-purpose terminal. The present invention will be described with respect to the multi-purpose terminal.  
         [0022]     A first card CA 1  and a second card CA 2  are a terrestrial card and a satellite card, respectively. Both the first and second card, CA 1  and CA 2 , include a receiving section for receiving a digital multimedia broadcast signal, a memory unit  330  for temporarily storing the digital multimedia broadcast signal, an interface unit  320  for controlling a serial port interface (SPI) interfacing with a ME, and an input/output unit  315  including nodes for inputting/outputting a signal from/to the appropriate card.  
         [0023]     The receiving section of the first card CA 1  includes an RF unit  510  for receiving a terrestrial digital multimedia broadcast signal through an antenna ANT, a terrestrial baseband processing/demodulating unit  530  for converting the terrestrial digital multimedia broadcast signal into a baseband signal and demodulating the converted signal and a controller  520  for controlling the reception and conversion operations.  
         [0024]     The receiving section of the second card CA 2  includes an RF unit  515  for receiving a satellite digital multimedia broadcast signal through an antenna ANT, a satellite baseband processing/demodulating unit  535  for converting the satellite digital multimedia broadcast signal into a baseband signal and demodulating the converted signal, and a controller  525  for controlling the reception and conversion operations.  
         [0025]     The memory unit  330  may be a flash memory.  
         [0026]     The interface unit  320  interfaces the first card CA 1  or the second card CA 2  with the ME. The interface unit  320  may be realized by using a SPI communication scheme or the like.  
         [0027]     The input/output unit  315  includes a chip selection (CS) node  311 , a SDI node  312  and a CLK node  313 . When the CS node  311  is in an active state, it is possible to transmit data from the first card CA 1  or second card CA 2  to the ME. The SDI node  312  is used to transmit data from the first card CA 1  or second card CA 2  to the ME. The CLK node  313  outputs clock signals, which are used for synchronization when data is transmitted from the first card CA 1  or second card CA 2  to the ME.  
         [0028]     The ME includes a DSP unit  210  for processing digital multimedia broadcast video/audio data, and a controller  220 . In  FIG. 2 , a display unit and a speaker for outputting final-processed video signals and audio signals, respectively, are not shown. Also not shown are components for other functions such as a communication function when the mobile equipment is a DMB-compatible portable telephone, and a navigation function when the mobile equipment is a navigation terminal, having no connection with the digital multimedia broadcast.  
         [0029]     When the first card CA 1  or second card CA 2  is inserted into the ME, and the CS node of the first card CA 1  or second card CA 2  is shifted into an active state, the controller  220  outputs a CS signal to the DSP unit  210 . Also, when the first card CA 1  or second card CA 2  is inserted into the ME, the controller  220  checks whether the inserted card refers to a satellite digital multimedia broadcast or a terrestrial digital multimedia broadcast, based on a commend (CMD) signal. Then, based on the result of the check, the controller  220  outputs an algorithm selection (SW-sel) signal for performing an appropriate processing to the DSP unit  210 .  
         [0030]     A clock signal (CLK) and data (DAT) are input directly to the DSP  210  through the CLK node  313  and the SDI node  312  of the first card CA 1  or second card CA 2 .  
         [0031]      FIG. 3  is a flowchart illustrating the procedure for processing satellite digital multimedia broadcast and terrestrial digital multimedia broadcast while distinguishing the satellite digital multimedia broadcast from terrestrial digital multimedia broadcast in the ME for reproducing the digital multimedia broadcast according to the present invention.  
         [0032]     When a first card CA 1  or second card CA 2  is inserted into the ME by the user, the controller  220  senses it, and initializes (e.g. sets a relevant register as a default value) the inserted card in step  3 A. In step  3 B, the controller  220  checks whether the inserted card is an input/output (I/O) card or a memory card. When the controller determines that the inserted card is an I/O card, the controller  220  proceeds to step  3 C, in which the controller  220  checks whether the inserted card is a terrestrial card or satellite card. When the controller determines that the inserted card is a terrestrial card, the controller  220  proceeds to step  3 D, in which the controller  220  prepares to decode a terrestrial DMB reception signal. In contrast, when the controller determines in step  3 C that the inserted card is a satellite card, the controller  220  proceeds to step  3 E, in which the controller  220  prepares to decode a satellite DMB reception signal. Herein, the preparation for signal decoding involves determining either the terrestrial or the satellite DMB reception signal decoding software executed by the DSP  210 .  
         [0033]     In step  3 B or  3 C, a CMD can be used to determine which card is inserted into the ME. Since either a SDIO card or an SD memory card may be inserted into an SDIO card slot, it is first determined which of these two types is inserted. Then, it is determined whether the inserted card is a terrestrial card or satellite card according to the next CMD. The CMD can be realized by using software. Hereinafter, the CMD will be described in detail.  
         [0034]     An SD card can be used as an SDIO card or normal memory card. Also, the SD card can be used in a normal SD mode or an SPI mode. CMD represents a commend to perform an operation in the SD mode of the SD card. Although not shown, when the SD card is used in an SD mode, data, clock and CMD lines are used. Therefore, actual data is transmitted through the data line, and commends to read and write data are transmitted through the CMD line. It is determined whether a card is used as an SDIO card or a normal memory card according to the CMD. According to the SDIO card standard, a plurality of CMDs to be used have been defined, including CMD 5 . After the SD card is initialized, the CMD 5  is transmitted to the SD card. When a response to the CMD 5  is received from the SD card, the SD card is recognized as an SDIO card. After the SD card is recognized as an SDIO card, the type of the SDIO card is determined according to a CMD. The mobile equipment sends a signal to the card to determine the type of DMB card inserted into the ME through the CMD line and determines whether the inserted DMB card is a terrestrial DMB card or a satellite DMB card based on a response signal received through the CMD line. A terrestrial DMB software operates when it is determined that the inserted card is a terrestrial DMB card, and a satellite DMB software operates when it is determined that the inserted card is a satellite DMB card. After such card recognition is finished, mode is shifted from the SD mode to the SPI mode in order to transmit data to the DSP  210 .  
         [0035]      FIG. 4  is a block diagram illustrating the structures of a ME for reproducing digital multimedia broadcasts and two cards for receiving different digital multimedia broadcasts according to the present invention.  
         [0036]     Memory cards may be a type of non-volatile memory card, in which stored data are not erased even while power is off. For example, the memory card includes type I/II of a compact flash (CF), a personal computer memory card international association (PCMCIA), a secure digital input output (SDIO) and a normal card. The following description will be given with respect to the SDIO card.  
         [0037]     When a DSP chip for processing digital multimedia broadcast video/audio data in a ME is a chip for an SPI communication scheme, it is necessary to use a memory card. The SPI communication scheme enables the SDIO card to be connected with various processors.  
         [0038]     When the SDIO card is used in an SPI mode, each node is defined as follows:  
         [0039]     A CS node  311  is a chip selection node for data enablement when data is transmitted from CA 3  (a terrestrial card) or CA 4  (a satellite card) to the ME. A CLK node  313  is a clock node, which is used to synchronize the CA 3  or CA 4  to the ME when data is transmitted from the CA 3  or CA 4  to the ME. An SDI node  314  is a node used to transmit data to the CA 3  or CA 4 . Although not shown, according to the SDIO card standard, existing nodes relating to power and reserved nodes may also be included.  
         [0040]     A coupling unit  450  functions to couple a card mode  350  and a receiving unit  550 . Reference numeral  350  may be configured with the same structure as that of the existing SDIO. However, reference numeral  350  does not form one card by itself, but forms one card together with the coupling unit  450  and the receiving unit  550 . Thus, reference numeral  350  is called “SDIO card module”. In addition, only the receiving units  550  are separately manufactured for the satellite digital multimedia broadcast and the terrestrial digital multimedia broadcast, but the SDIO card module  350  is shared for the broadcasts. Therefore, the coupling unit  450  may be configured to couple the SDIO card module to a receiving unit for the satellite digital multimedia broadcast or to couple a receiving unit for the terrestrial digital multimedia broadcast to the SDIO card module.  
         [0041]     A memory unit  330  may be configured with a flash memory.  
         [0042]     As described above, the present invention provides a digital multimedia broadcast receiver, to which two cards using different frequencies can be selectively connected and disconnected, so that the user can easily view both satellite and terrestrial digital multimedia broadcasts with a single receiver through card change.  
         [0043]     While the present invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, the scope of the invention is not to be limited by the above embodiments but by the claims and the equivalents thereof