WO2008016211A1

WO2008016211A1 - Digital broadcasting system and method

Info

Publication number: WO2008016211A1
Application number: PCT/KR2007/001499
Authority: WO
Inventors: Duk Won Oh; Won Cheol Eun; Heon Ju Park; Ju Young Choi; Jae Man Lim; Suk Woo Jung; Kwang Ju Kim
Original assignee: Tu Media Corp.
Priority date: 2006-07-31
Filing date: 2007-03-27
Publication date: 2008-02-07
Also published as: KR20080011585A; KR100858391B1

Abstract

The present invention relates to a digital broadcasting system and method. A digital broadcasting transmitting apparatus transmits message data using an idle band of a broadcasting channel. A terminal flickers a logo at the top of a standby screen so as to notify a recipient that the message data has been received, and displays a message on a screen when the recipient selects a shortcut key. According to the present invention, since a message can be sent without needing recipient's permission, and a message can be sent to a recipient who is not watching a broadcast program, the message can be sent according to a service provider's plan, inconvenience to the recipient when the recipient receives a message while watching the broadcast program can be reduced, and the message is stored in a storage unit of a terminal and can be rechecked. Accordingly, a service for providing information and advertisement to the recipient can be reinforced. In addition, since the message is transmitted using a broadcasting channel in which an idle band is generated, a band is not additionally allocated, thereby improving economic efficiency.

Description

Description DIGITAL BROADCASTING SYSTEM AND METHOD

Technical Field

[1] The present invention relates to a digital broadcasting system and method, and more particularly, to a digital broadcasting system and method that can improve a message notification service for information and advertisement. Background Art

[2] FIG. 1 is a diagram illustrating a method of transmitting digital information according to a general satellite digital multimedia broadcasting method. As shown in FIG. 1, a satellite digital multimedia broadcasting service is provided through a band of approximately 2.535 to 2.655 GHz corresponding to an ultrahigh frequency (UHF), which is much higher than a ground wave.

[3] In the ground-based digital multimedia broadcasting, an electric wave is sent from a mountain or a building on the ground toward an urban area. However, the satellite digital multimedia broadcasting can provide a service on a national network by sending an electric wave to everywhere around the country from a satellite outside the atmosphere.

[4] In a broadcasting center including an uplink center, program providers, broadcasting companies, PSTN (Public Switched Telephone Network) service providers, PDN (Public Data Network) service providers, and the like transmit transmission signals carrying various kinds of diversely programmed contents, such as news articles, music videos, sports, movies, dramas, songs, foreign languages, stock market information, traffic information, weather information, and the like to the satellite through a Ku-band frequency (approximately 13.824 to 13.883 GHz).

[5] The satellite transmits the received transmission signals to cellular phones and

PDAs on the ground through an S-band allocated to the DMB (Digital Multimedia Broadcasting). When it is difficult to directly receive the transmission signals transmitted from the satellite, the transmission signals are transmitted to terminals on the ground through a repeater, called a gap filler. Therefore, it is possible to use the digital multimedia broadcasting service anywhere at any time without temporal and spatial limitations.

[6] In particular, the ground-based digital multimedia broadcasting can has broadcasting channels that generally include approximately five video channels and nine audio channels, while the satellite digital multimedia broadcasting can provides more services of approximately twelve video channels and twenty-six audio channels.

[7] In the satellite digital multimedia broadcasting, when a terminal receives a digital signal from the satellite, a demultiplexer separates the received digital signal into audio, video, and data signals, and PSI (Program Specific Information) and SI (Service Information) based on the program units.

[8] In particular, the program specific information and the service information include information to be obtained by reconstructing the received audio, video, and data signals, such as output time, type, and play time of a program to broadcast, match time of audio, video, and data information, and the like.

[9] The program specific information and the service information are transmitted as a transport stream together with information regarding a broadcast program when a broadcasting station transmits the broadcast program to the satellite. Then, a receiver that has received the transport stream separates the audio, video, and data signals, and the program specific information and the service information from the transport stream, and decodes and plays them.

[10] In the related art, in addition to the above-described main service, there is provided a mail service (hereinafter, referred to as a "B-mail service") that transmits a broadcasting mail (hereinafter, referred to as a "B-mail") for providing information or advertisement to a subscriber on the basis of EMM (Entitlement Management Message) information generated by the CAS (Conditional Access System). The B-mail pops up on a display device of the terminal while the subscriber is watching the broadcast program, and then the subscriber notices the B-mail. Disclosure of Invention

Technical Problem

[11] However, the B-mail is recognizable only when the subscriber is watching the broadcast program, and it pops up on the display device of the terminal, which may disturb the subscriber in watching the broadcast program. Further, since only text data can be transmitted, various expressions cannot be made. In addition, since the B-mail is deleted, not saved, if the subscribed presses a predetermined key (for example, an "OK" key) of the terminal, the intended message cannot be sufficiently delivered to the subscriber.

[12] For these reasons, instead of the B-mail service, the information is notified using the SMS (Short Message Service: which allows users of cellular phones to receive and transmit short messages without needing additional apparatus) that uses a network of a mobile communication service provider. However, since the SMS can be provided to only recipients who give permission, not-permitted SMS messages may be considered as spam. Further, the user should pay a predetermined fee whenever he/she sends an SMS message.

[13] The present invention has been finalized in order to solve the above-described problem, and it is an object of the present invention to provide a digital broadcasting system and method that can send a message without needing the recipient's permission, send a message to a recipient when the recipient does not watch a broadcast program, minimize inconvenience to the recipient when the recipient receives a message while watching the broadcast program, and store the message such that the recipient can recheck the message later. Technical Solution

[14] According to an embodiment of the present invention, a digital broadcasting system includes a storage unit that stores message data, a data broadcasting server that outputs the message data read from the storage unit according to a prescribed schedule, a PSI/ SI (Program Specific Information/Service information) server that receives the message data from the data broadcasting server, and generates and outputs a program specific information table and a service information table according to the received message data, and a transmitter that transmits the program specific information table and the service information table, and transmits the message data to an idle band of a broadcasting channel.

[15] According to another embodiment of the present invention, a digital broadcasting method includes the steps of storing message data in a storage unit, causing a data broadcasting server to read the message data from the storage unit and to output the read message data according to a prescribed schedule, causing a PSI/SI server to receive the message data from the data broadcasting server and to generate and output a program specific information table and a service information table according to the received message data, and causing a transmitter to transmit the program specific information table and the service information table and to transmit the message data to an idle band of a broadcasting channel.

[16] According to still another embodiment of the present invention, a digital broadcasting method includes steps of causing a terminal to wake up at a predetermined cycle or at a prescribed reserved time and to receive an SDTT, causing the terminal to recognize and receive message data with reference to the received SDTT, causing the terminal to flicker a logo at the top of a standby screen on a display device of the terminal such that a recipient recognizes the received message data, and causing the terminal to display a message on the screen when the recipient, who recognizes the flickering of the logo, selects a shortcut key of the terminal.

Advantageous Effects

[17] According to the present invention, since a message can be sent without needing the recipient's permission, and a message can be sent to a recipient when the recipient is not watching a broadcast program, the message can be sent according to a service provider's plan, inconvenience to the recipient when the recipient receives a message while watching the broadcast program can be reduced. Further, since the message can be stored in a storage device of a terminal and the recipient can recheck the message, an information and advertisement service for the recipient can be reinforced. Further, since the message is transmitted through a broadcasting channel in which an idle band occurs, an additional band does not need to be allocated, thereby increasing economic efficiency. Brief Description of the Drawings

[18] FIG. 1 is a diagram illustrating a method of transmitting digital information according to a general satellite digital multimedia broadcasting method.

[19] FIG. 2 is a schematic view of a digital broadcasting system according to a preferred embodiment of the present invention.

[20] FIG. 3 is a schematic view of a digital broadcasting transmitting apparatus shown in

FIG. 2.

[21] FIG. 4 is a flowchart schematically illustrating a process of receiving and checking a message according to an embodiment of the present invention.

[22] FIG. 5 is a diagram showing an interface screen to be displayed on a display device of a terminal, which has received a message, according to an embodiment of the present invention.

[23] FIG. 6 is a diagram showing an interface screen to be displayed on the display device of the terminal, which has received a message, according to another embodiment of the present invention. Mode for the Invention

[24] Hereinafter, a digital broadcasting system and method according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

[25] First, a digital broadcasting system according to a preferred embodiment of the present invention will be described.

[26] As shown in FIG. 2, in a digital broadcasting system according to an embodiment of the present invention, a digital broadcasting transmitting apparatus 201 (hereinafter, simply referred to as a "transmitting apparatus") creates a multimedia message, which includes at least one of a moving picture, an image, and an image sequence, as a message that informs a broadcast program or delivers an announcement, and stores the created multimedia message. Then, if the transmitting apparatus 201 transmits the multimedia message to a satellite 202 according to a planned schedule, the satellite 202 receives the transmitted message and transmits the received message to a terminal 203 on the ground. [27] The transmitting apparatus 201 uses broadcasting channels that include a pilot channel 204, a CAS (Conditional Access System) channel 205, an EPG (Electronic Program Guide) channel 206, a video channel 207, an audio channel 208, and a data channel 209.

[28] In general, physical construction information of each of the video, audio, and data channels 207, 208, and 209, is transmitted through the pilot channel 204, recipient's access control information to the video, audio, and data channels 207, 208, and 209 is transmitted through the CAS channel 205, and program guide information regarding the video, audio, and data channels 207, 208, and 209 is transmitted through the EPG channel 206.

[29] Further, the content of the broadcast program is generally transmitted through the video, audio, and data channels 207, 208, and 209. Since a bandwidth of each of the channels 204 to 209 is not fixedly allocated, data can be transmitted through all of the channels 204 to 209.

[30] In this embodiment of the present invention, a message is transmitted through a channel in which an idle band is generated among the broadcasting channels 204 to 209. For example, the message can be transmitted through the EPG channel 206 that transmits the program guide information.

[31] For example, in a case of guide information on a program that is broadcast at 3 a.m., the size of broadcast program guide information is at its largest at 3 a.m. and then gradually decreases. As the size of broadcast program guide information decreases, an idle bandwidth of the EPG channel 206 gradually increases. Therefore, the message is transmitted using the increased idle band.

[32] In another example, in the case of the video, audio, and data channels 207, 208, and

209, since the size of data that is transmitted when there is no broadcasting is decreased, an idle band may be generated. Therefore, a message can be transmitted using the generated idle band.

[33] Therefore, message notification can be performed without allocating an additional band, thereby improving economic efficiency.

[34] Next, the specific structure of the transmitting apparatus 201 according to the embodiment of the present invention will be described in detail.

[35] As shown in FIG. 3, the transmitting apparatus 201 includes a contents server 301 that registers and manages message (for example, mail) data to be transmitted, a schedule server 302 that plans a transmission time of the message to be transmitted and generates schedule information, a storage unit 303 that stores the message data and the schedule information of the message data, and a data broadcasting server 304 that reads the message data and the schedule information stored in the storage unit 303 and outputs the message data and file information of the message data according to the read schedule information.

[36] The transmitting apparatus 201 further includes an encoder 305 that receives the message data from the data broadcasting server 304 and encodes the received message data, a PSI/SI (Program Specific Information/Service information) server 306 that receives the file information of the message data from the data broadcasting server 304 and generates a program specific information table and a service information table, a multiplexer 307 that receives the message data encoded by the encoder 305 and the program specific information table and the service information table generated by the PSI/SI server 306 so as to convert them into a TS (Transport Stream), and a transmitter 308 that receives the transport stream from the multiplexer 307 and transmits the received transport stream.

[37] Here, the transmitter 308 transmits the program specific information table and the service information table through the CAS channel 205, the EPG channel 206, the video channel 207, or the audio channel 208 according to the purpose. Further, the transmitter 308 transmits the message data using an idle band of the corresponding channel in which the idle band is generated.

[38] For reference, in this embodiment of the present invention, the components 301 to

308 of the transmitting apparatus 201 are exemplified as individual servers or devices. However, it will be apparently understood by those skilled in the art that the components 301 to 308 may be incorporated into one computer device according to design.

[39] The operation of the digital broadcasting system having the above-described structure will be described in detail.

[40] A service provider writes a message including advertisement or guide information so as to inform broadcast programs or deliver announcements to a service subscriber (who is an unspecified majority, refers to those who use a message service according to an embodiment of the present invention, including those who subscribe to the service, do not subscribe to the service, terminate the service, and stop using the service, and hereinafter, is simply referred to as a "recipient"), and then the service provider registers data of the message in the form of an electronic file in the contents server 301. Then, the contents server 301 stores the registered message data in the storage unit 303.

[41] Here, the message may be a multimedia message that includes at least one of a moving picture, an image, and an image sequence. For reference, since a technique that generates the multimedia message including the moving picture, the image, and the image sequence is known to those skilled in the art, the description thereof will be omitted.

[42] The service provider arranges or changes a schedule such that the message data can reach the recipient at an appropriate time or registers the schedule information according to the arranged or changed schedule in the schedule server 302. The schedule server 302 stores the registered schedule information in the storage unit 303 and simultaneously notifies the data broadcasting server 304 that the schedule information is stored.

[43] When the schedule server 302 notifies the data broadcasting server 304 that the schedule information is stored, the data broadcasting server 304 reads the message data and the schedule information stored in the storage unit 303 and transmits file information of the read message data according to the read schedule information to the encoder 305. The data broadcasting server 304 transmits the message data to the encoder 305 and simultaneously transmits the file information of the message data to the PSI/SI server 306. Here, the file information of the message data is information that is used when the PSI/SI server generates the program specific information table and the service information table of the message data.

[44] The encoder 305 receives the message data from the data broadcasting server 304, encodes the received message data according to a DSM-CC (Digital Storage Media Command and Control) method, and outputs the encoded message data. Here, the DSM-CC is an open protocol that instructs and controls a digital storage media (DSM), which is a device that stores digital information and transmits the stored information, and that defines a function in relation to selection of a bit stream, and stream control, storage, and management, and an interface. The DSM-CC is a known technique.

[45] The PSI/SI server 306 generates a program specific information table and a service information table on the basis of the information of the message data transmitted by the data broadcasting server 304, sections the generated program specific information table and service information table, and outputs the sectioned tables.

[46] The program specific information table includes information that is necessary when demultiplexing the transport stream received by the recipient's terminal 203. Therefore, the terminal 203 decodes the received program specific information table, and multiplexes and restores video, audio, and data signals according to the information included in the decoded program specific information table. As a result, a service is provided to the recipient through the terminal 203.

[47] The program specific information table includes a PAT (Program Association

Table), a PMT (Program Map Table), a CAT (Condition Access Table), and an NIT (Network Information Table). The PMT assigns a value of PID (Packet Identification) of the transport stream.

[48] Here, the PID is an identifier that is given to packets in the multiplexed transport stream. The PID is an identification value. When a channel signal is independently compressed and packetized, and compressed packets are multiplexed and transmitted in the form of a transport stream, the same PID value is given to each of the packets corresponding to the same channel signal, to thereby distinguish the packets from packets of other channels. A receiver can select (demultiplex) packets corresponding to a desired channel from the multiplexed transport stream using the PID.

[49] The service information table includes an SDT (Service Description Table), an EIT

(Event Information Table) (p/f), an EIT (Event Information Table) (sch), a BIT (Broadcaster Information Table), a TOT (Time Offset Table), and an SDTT (Software Download Trigger).

[50] The transmitting apparatus 201 sends download signal to the terminal 203 that switches from an idle state to a wake -up state on the basis of the SDTT so as to inform that the message is being transmitted. Here, the idle state refers to a state in which the terminal is turned on but does not receive digital broadcasting, and the wake -up state refers to a state in which the terminal receives the digital broadcasting or the recipient is watching the digital broadcast program.

[51] In this embodiment of the present invention, for download signaling, information is carried on the SDTT, a Download Contents descriptor, the PMT, a Stream Identifier descriptor, and a Carousel Identifier descriptor.

[52] The multiplexer 307 packetizes the encoded message data output from the encoder

305, the sectioned program specific information table and service information table output from the PSI/SI server 306, that is, the PSI/SI tables, and outputs the packetized message data, program specific information table, and service information table in a transport stream.

[53] The transmitter 308 uses the broadcasting channels, which are used to provide the broadcasting service and include the pilot channel 204, the CAS channel 205, the EPG channel 206, the video channel 207, the audio channel 208, and the data channel 209. The transmitter 308 transmits the message data in the transport stream through a channel in which an idle band is generated among the broadcasting channels 205 to 209.

[54] For example, since EPG information transmitted through the EPG channel 206 is guide information regarding broadcast programs, when the broadcasting of the corresponding program ends, the size of data is decreased. Therefore, in the case of the EPG channel 206 that transmits the EPG information, the size of data is gradually decreased as it approaches broadcasting end time, and thus the idle bandwidth is increased. Therefore, the message can be transmitted using the increased idle band.

[55] In another example, since the broadcast programs are transmitted through the video, audio, and data channels 207, 208, and 209, the size of data transmitted when there is no broadcasting is decreased, and thus the idle band is generated. Therefore, the message can be transmitted using the idle band. [56] Therefore, according to the embodiment of the present invention, since the message is transmitted using the idle band, the message service can be provided without allocating an additional band, thereby improving economic efficiency.

[57] The EPG, and the video, audio, and data channels 207, 208, and 209 taken as examples can be changed according to a channel allocation policy of the service provider. In addition, a message can be transmitted using an idle band of another channel.

[58] The message transmitted by the transmitting apparatus 201 according to the above- described process is transmitted to the recipient's terminal 203 through the satellite 202 or transmitted to the recipient's terminal 203 through the satellite 202 and a gap filler. This is a known technique, and thus the description thereof will be omitted.

[59] An antenna that is provided in the recipient's terminal 203 receives the transport stream including the message data transmitted by the transmitting apparatus 201 through the satellite 202. The received transport stream is restored by being processed through a converter, a CDM (Code Division Multiplexing) demodulator, a demultiplexer, and a decoder. The restored message is displayed on a display device of the recipient's terminal.

[60] Hereinafter, a method of detecting a message from a transport stream according to an embodiment of the present invention will be described. First, several assumptions will be described.

[61] A message service according to an embodiment of the present invention is provided using a BNDS (Broadcast Network Download Service), and a logo ID is given to the message.

[62] A known transmitting apparatus updates an SDTT once a day and does not transmit a PMT and an SDTT when logo data is not transmitted. The known transmitting apparatus transmits the SDTT only when a carousel, which transmits a message, is transmitted.

[63] Meanwhile, the transmitting apparatus 201 according to the embodiment of the present invention is configured such that message data can be transmitted at any time through a channel in which an idle band is generated, and the SDTT is updated at least once a day according to a prescribed number of times.

[64] In order to receive the message data, the terminal 203 needs to switch from an idle state to a wake-up state. Therefore, the terminal 203 according to the embodiment of the present invention includes a wake-up program that wakes up at a predetermined cycle, and previously receives and stores a transmission reservation table that indicates a time when the message is to be transmitted.

[65] Even in the idle state, the terminal 203 wakes up at the predetermined cycle or at the time corresponding to the transmission reservation table, and checks whether the SDTT is detected.

[66] When the SDTT is detected, the terminal 203 recognizes that the message data is transmitted through the channel having the idle band, and can receive the message through the channel having the idle band. Further, the terminal 203 can search the logo ID of the message, detect logo data, and demultiplex the message data with reference to the program specific information table and the service information table.

[67] According to the embodiment of the present invention, since the message is provided using the BNDS, the recipient can store the message in the terminal, recheck the message stored in the terminal if necessary, and receive the message at a time different than the time when watching the broadcast program.

[68] Therefore, the service provider can transmit a message at the time according to a service provider's plan, send a message without needing recipient's permission, and send a message even if the recipient does not watch a broadcast program. Accordingly, an efficient advertisement effect can be obtained.

[69] Hereinafter, a method of checking a message according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[70] FIG. 4 is a flowchart schematically showing a process of receiving and checking a message according to an embodiment of the present invention.

[71] As shown in FIG. 4, the transmitting apparatus 201 according to the embodiment of the present invention transmits message data through a channel in which an idle band is generated, and transmits a program specific information table and a service information table corresponding to the message data through a corresponding channel according to the purpose (Step SOOl). Here, the terminal 203 previously receives and stores a transmission reservation table that indicates the time when the message is to be transmitted.

[72] In an idle state where power is turned on, the terminal 203 wakes up at a predetermined cycle and the reserved time recorded in the transmission reservation table, and checks whether or not an SDTT of the service information table is detected (Step S002).

[73] When the SDTT is detected, the terminal 203 recognizes that a message is transmitted through the channel having the idle band, receives the message through the channel having the idle band, and also receives the program specific information table and the service information table (Step S003).

[74] The terminal 203, which has received the message, searches a logo ID, detect logo data, and demultiplexes the message data with reference to the program specific information table and the service information table.

[75] When the message is received, the terminal 203 flickers a logo of the service provider at the top of a standby screen displayed on a display device of the terminal so as to inform the recipient that the message has arrived (Step S004).

[76] When the flickering of the logo allows the recipient to recognize that the message has been received, and the recipient presses a shortcut key (hot key), the terminal 203 displays a message on the display device of the terminal (Step S005)

[77] The recipient can check the message for a predetermined time. Since the message disappeares on the display device after the predetermined time, the recipient resumes watching the broadcast program (Step S006).

[78] FIG. 5 is a diagram showing an interface screen to be displayed on a display device of a terminal, which has received a message, according to an embodiment of the present invention. As shown in FIG. 5, a control unit of the terminal 203 flickers the logo 501 of the service provider at the top of the standby screen (a) on the display device of the terminal 203 so as to inform the recipient that the message has arrived. The logo 501 continues flickering until the recipient selects the shortcut key so as to check the message.

[79] When the recipient, who recognizes the flickering of the logo 501, selects the shortcut key so as to check the message, the terminal 203 displays the message through a channel access screen (b) of the digital broadcasting. Then, the user can check the message for a predetermined time, and the terminal 203 deletes the message after the predetermined time.

[80] Next, the terminal 203 plays the digital broadcasting, such that the recipient can watch a broadcast program (c).

[81] Further, when the recipient does not check the message data received while watching the broadcast program, the terminal 203 notifies the recipient that the message data has been received by repeatedly flickering the logo 501 on the standby screen after the recipient finishes watching the digital broadcasting.

[82] As described above, according to the embodiment of the present invention, the recipient is informed that the message has arrived according to the method of flickering the logo 501 at the top of the standby screen. Therefore, inconvenience to the recipient due to the message received while watching the broadcast program can be reduced.

[83] FIG. 6 is a diagram showing an interface screen to be displayed on a display device of a terminal, which has received a message, according to another embodiment of the present invention. As shown in FIG. 6, the message can be checked from a message box of the terminal 203 or a menu of a channel access screen that is provided on the display device of the terminal according to EPG information.

[84] The terminal 203 in the idle state wakes up according to a prescribed wake-up time or wakes up at a reserved time recorded in a transmission reservation table that indicates a time when the message is to be transmitted. Then, the terminal 203 receives and stores the message transmitted by the transmitting apparatus 201 through the satellite 202. Further, the terminal 203 receives and stores a message while watching a broadcasting service.

[85] For example, in order that the recipient can select a desired message, the terminal

203 displays a "message box" menu using the display device, as shown in (a) in FIG. 6. When the recipient selects a message receiving box on the "message box" menu, the terminal 203 displays the content of the message on the display device, as shown in (c) of FIG. 6.

[86] In another example, as shown in (b) of FIG. 6, the terminal 203 displays a "channel guide" menu according to the EPG information on the display device of the terminal. When the recipient selects a message box on the "channel guide" menu, as shown in (a) of FIG. 6, the "message box" menu is displayed. When the recipient selects the "message receiving box" on the "message box" menu, as shown in (c) of FIG. 6, the content of the message is displayed on the display device.

[87] As described above, according to the embodiments of the present invention, since the message is provided to the recipient through the BNDS, the message can be stored. Accordingly, the recipient can recheck the stored message if necessary. Further, since the terminal 203 wakes up at a predetermined cycle or at a reserved time and receives the message, the service provider can send a message at a time other than the broadcast time or whenever necessary. In addition, by the flickering of the logo 501, the recipient is informed that the message has arrived without being interrupted while watching a broadcast program, thereby obtaining an efficient advertisement effect.

Claims

[1] A digital broadcasting system comprising: a storage unit that stores message data; a data broadcasting server that outputs the message data read from the storage unit according to a prescribed schedule; a PSI/SI (Program Specific Information/Service information) server that receives the message data from the data broadcasting server, and generates and outputs a program specific information table and a service information table corresponding to the received message data; and a transmitter that transmits the program specific information table and the service information table, and transmits the message data in an idle band of a broadcasting channel.

[2] The digital broadcasting system as set forth in claim 1, wherein the message is a multimedia message that includes at least one of a moving picture, an image, and an image sequence.

[3] The digital broadcasting system as set forth in claim 1, wherein the message data is transmitted using an idle band of an EPG (Electronic Program Guide) channel, which transmits program guide information, among broadcasting channels.

[4] The digital broadcasting system as set forth in claim 1, wherein the message data is transmitted in an idle band that is generated when there is no broadcasting.

[5] The digital broadcasting system as set forth in claim 1, further comprising: a contents server that generates the message data and stores the generated message data in the storage unit.

[6] The digital broadcasting system as set forth in claim 1, further comprising: an encoder that receives the message data from the data broadcasting server, and encodes and outputs the received message data, wherein the transmitter transmits the message data encoded by the encoder.

[7] The digital broadcasting system as set forth in claim 6, further comprising: a multiplexer that converts the message data received from the encoder and the program specific information table and the service information table received from the PSI/SI server into a transport stream, and outputs the converted transport stream, wherein the transmitter transmits the transport stream output from the multiplexer.

[8] The digital broadcasting system as set forth in claim 1, wherein the service information includes an SDTT (Software Download Trigger Table), and the SDTT is updated at a predetermined cycle.

[9] The digital broadcasting system as set forth in claim 8, further comprising: a digital broadcasting terminal that switches from an idle state to a wake-up state at a predetermined cycle or at a prescribed reserved time, receives the SDTT, receives the message data on the basis of the received SDTT, and displays that the message data has been received.

[10] The digital broadcasting system as set forth in claim 9, wherein the terminal flickers a logo at the top of a standby screen so as to notify a recipient that the message data has been received, and displays a message on the screen when the recipient selects a shortcut key.

[11] A digital broadcasting method comprising the steps of: storing message data in a storage unit; causing a data broadcasting server to read the message data from the storage unit and to output the read message data according to a prescribed schedule; causing a PSI/SI server to receive the message data from the data broadcasting server and to generate and output a program specific information table and a service information table corresponding to the received message data; and causing a transmitter to transmit the program specific information table and the service information table and to transmit the message data in an idle band of a broadcasting channel.

[12] The digital broadcasting method as set forth in claim 11, wherein the message is a multimedia message that includes at least one of a moving picture, an image, and an image sequence.

[13] The digital broadcasting method as set forth in claim 11, wherein the message data is transmitted using an idle band of an EPG (Electronic Program Guide) channel, which transmits program guide information, among broadcasting channels.

[14] The digital broadcasting method as set forth in claim 11, wherein the message data is transmitted in an idle band that is generated when there is no broadcasting.

[15] The digital broadcasting method as set forth in claim 11, wherein the step of causing the transmitter to transmit the message data further includes a step of causing an encoder to encode the message data received from the data broadcasting server, and the transmitter transmits the encoded message data.

[16] The digital broadcasting method as set forth in claim 15, wherein the step of causing the transmitter to transmit the message data further includes a step of causing a multiplexer to multiplex the encoded message data, the program specific information table, and the service information table into a transport stream, and to output the multiplexed transport stream, and the transmitter transmits the multiplexed transport stream.

[17] A digital broadcasting method comprising the steps of: causing a terminal to wake up at a predetermined cycle or at a prescribed reserved time and receive an SDTT; causing the terminal to recognize and receive message data with reference to the received SDTT; causing the terminal to flicker a logo at the top of a standby screen on a display device of the terminal such that a recipient recognizes the received message data; and causing the terminal to display a message on the screen when the recipient, who recognizes the flickering of the logo, selects a shortcut key of the terminal.

[18] The digital broadcasting method as set forth in claim 17, wherein the terminal repeatedly flickers the logo on the standby screen after the recipient finishes watching a broadcast program so as to notify the recipient that the message data has been received when the recipient did not check the message data received while watching the broadcast program.