WO2008016213A1

WO2008016213A1 - Digital broadcasting system and method

Info

Publication number: WO2008016213A1
Application number: PCT/KR2007/001501
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: KR20080011587A; KR100831959B1

Abstract

The present invention relates to a digital broadcasting system and method. A digital broadcasting transmitting apparatus transmits a channel change screen using an idle band of a broadcasting channel, and a terminal receives the channel change screen and displays the channel change screen on a display device during a channel change time. According to the present invention, it is possible to perform advertisement and public relations according to event and commercial plans of a service provider through various channel change screens. Further, it is possible to increase service satisfaction by providing things to see to a viewer during the channel change time, which may cause a sense of boring. In addition, according to the present invention, it is possible to create a new business model that aims at a niche market for advertisement.

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 provides a channel change screen. 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).

[6] In the satellite digital multimedia broadcasting, when the 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) on the basis of programs.

[7] 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.

[8] 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.

[9] 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.

[10] 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.

[11] In general, in the case of the satellite digital multimedia broadcasting, when a broadcasting channel changes, a small amount of time delay (approximately 3 to 8 seconds) occurs until broadcasting data of a new channel is loaded and played. In an embodiment of the present invention, the delay time when a channel changes is referred to as "channel change time". Disclosure of Invention

Technical Problem

[12] In the related art, since a simple logo of a service provider is only displayed on a standby screen during the channel change time, the current broadcasting trend, which aims at a multimedia contents service, is not reflected, and a viewer feels a sense of boring.

[13] Further, in the related art, the EPG (Electronic Program Guide) is provided to provide the broadcast program guide information to the listener. However, the EPG causes inconvenience in that the listener needs to select and search desired information. Further, since the EPG is passively provided, the EPG is not enough to positively advertise broadcast programs. In addition, since the EPG only provides program guide information, it is difficult to advertise various contents and services.

[14] The 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 positively and effectively advertise broadcast programs and deliver various kinds of events and commercials through a channel change screen during a channel change time, and provides convenience such that a viewer do not feel a sense of boring. Technical Solution [15] According to an embodiment of the present invention, a digital broadcasting system includes a storage unit that stores channel change screen data, a data broadcasting server that outputs the channel change screen data read from the storage unit according to a prescribed schedule, a PSI/SI (Program Specific Information/Service information) server that receives the channel change screen data from the data broadcasting server, and generates and outputs a program specific information table and a service information table corresponding to the received channel change screen data, and a transmitter that transmits the program specific information table and the service information table, and transmits the channel change screen data in an idle band of a broadcasting channel.

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

[17] According to still another embodiment of the present invention, a digital broadcasting method includes the 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 channel change screen data with reference to the received SDTT, and causing, when a recipient selects a broadcasting channel, the terminal to display the received channel change screen on a display device of the terminal during a channel change time until the terminal loads broadcasting data of the selected channel and plays the loaded broadcasting data.

Advantageous Effects

[18] According to the present invention, since a channel change screen is transmitted using an idle band of a broadcasting channel, an additional band does not need to be allocated, and it is possible to perform advertisement and public relations according to event and commercial plans of a service provider through various channel change screens. Further, it is possible to increase service satisfaction by providing things to see to a viewer during the channel change time, which may cause a sense of boring. In addition, according to the present invention, it is possible to create a new business model that aims at a niche market for advertisement. Brief Description of the Drawings

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

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

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

FIG. 2.

[22] FIG. 4 is a schematic view showing a channel change screen according to an embodiment of the present invention.

[23] FIG. 5 is a flowchart schematically showing a process of displaying a channel change screen according to an 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] FIG. 2 is a conceptual view schematically illustrating a channel change screen service according to a preferred embodiment of the present invention.

[27] 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 channel change screen, including at least one of a moving picture, an image, and an image sequence, which informs broadcast programs or delivers announcements and various events, and stores the created channel change screen. Then, if the transmitting apparatus 201 transmits the channel change screen to a satellite 202 according to a planned schedule, the satellite 202 receives the transmitted channel change screen and transmits the received channel change screen to a terminal 203 on the ground.

[28] 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.

[29] 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.

[30] 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.

[31] In this embodiment of the present invention, channel change screen is transmitted through a channel in which an idle band is generated among the broadcasting channels 205 to 209. For example, the channel change screen can be transmitted using the idle band of the EPG channel 206 that transmits the program guide information.

[32] 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 channel change screen is transmitted using the increased idle band.

[33] 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, channel change screen can be transmitted using the generated idle band.

[34] Therefore, the channel change screen service can be provided without allocating an additional band, thereby improving economic efficiency.

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

[36] As shown in FIG. 3, the transmitting apparatus 201 includes a contents server 301 that registers and manages a channel change screen to be transmitted, a data schedule server 302 that plans a transmission time of the channel change screen to be transmitted and generates schedule information, a storage unit 303 that stores the channel change screen and the schedule information of the channel change screen, and a data broadcasting server 304 that reads the channel change screen and the schedule information stored in the storage unit 303 so as to output the channel change screen and file information corresponding to the channel change screen according to the read schedule information.

[37] The transmitting apparatus 201 further includes an encoder 305 that receives the channel change screen from the data broadcasting server 304 and encodes the received channel change screen, a PSI/SI (Program Specific Information/Service information) server 306 that reads the file information of the channel change screen from the data broadcasting server 304 so as to generate a program specific information table and a service information table, a multiplexer 307 that receives the channel change screen 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.

[38] 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 channel change screen data using an idle band of the corresponding channel in which the idle band is generated.

[39] 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.

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

[41] A service provider (who refers to a digital broadcasting service provider) creates channel change screen 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 channel change screen 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 the channel change screen data in the form of an electronic file in the contents server 301. Then, the contents server 301 stores the registered channel change screen data in the storage unit 303.

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

[43] Further, the channel change screen data stored in the contents server 301 may be a set of data on images or moving pictures regarding a plurality of channel change screens, and may be divided into a plurality of electronic files and then stored.

[44] The service provider arranges or changes a schedule such that the channel change screen 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. [45] When the schedule server 302 notifies the data broadcasting server 304 that the schedule information is stored, the data broadcasting server 304 reads the channel change screen and the schedule information stored in the storage unit 303 and transmits the read channel change screen according to the read schedule information to the encoder 305. The data broadcasting server 304 transmits the channel change screen to the encoder 305 and simultaneously transmits the file information of the channel change screen to the PSI/SI server 306. Here, the file information is information that is used when the PSI/SI server generates the program specific information table and the service information table of the channel change screen.

[46] The encoder 305 receives the channel change screen from the data broadcasting server 304, encodes the received channel change screen according to a DSM-CC (Digital Storage Media Command and Control) method, and outputs the encoded channel change screen. 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.

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

[48] 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, the service is provided to the recipient through the terminal 203.

[49] 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.

[50] 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.

[51] 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).

[52] 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 channel change screen 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.

[53] 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.

[54] The multiplexer 307 packetizes the encoded channel change screen output by the encoder 305, the sectioned program specific information table and service information table output by the PSFSI server 306, that is, the PSFSI tables, and outputs the packetized channel change screen, program specific information table, and service information table in a transport stream.

[55] 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 channel change screen in the transport stream through a channel in which an idle band is generated among the broadcasting channels 204 to 209.

[56] 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 amount of data is reduced. 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 band is increased. Therefore, the channel change screen can be transmitted using the increased idle band.

[57] 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 channel change screen can be transmitted using the idle band.

[58] Therefore, according to the embodiment of the present invention, since the channel change screen is transmitted using the idle band, the channel change screen service can be provided without allocating an additional band, thereby improving economic efficiency.

[59] The EPG, video, and audio channels 206, 207, and 208 taken as examples can be changed according to a channel allocation policy of the service provider. In addition, a channel change screen can be transmitted using an idle band of another channel.

[60] The channel change screen 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.

[61] An antenna that is provided in the recipient's terminal 203 receives the transport stream including the channel change screen 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 channel change screen is displayed on a display device of the recipient's terminal.

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

[63] A channel change screen 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 channel change screen.

[64] A known transmitting apparatus updates an SDTT once a day and does not transmit a PMT and an SDTT when download contents are not transmitted. The known transmitting apparatus transmits the SDTT only when a carousel, which transmits a channel change screen, is transmitted.

[65] Meanwhile, the transmitting apparatus 201 according to the embodiment of the present invention is configured such that a channel change screen 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.

[66] In order to receive the channel change screen, 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 channel change screen is to be transmitted.

[67] 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 or not the SDTT is detected.

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

[69] As described above, since the service provider can transmit a channel change screen at any time according to public relation strategy, thereby positively providing advertisement for the broadcast programs and various services.

[70] FIG. 4 is a schematic view showing a channel change screen according to an embodiment of the present invention. FIG. 5 is a flowchart schematically showing a process of displaying a channel change screen according to an embodiment of the present invention.

[71] As shown in the drawings, a channel change screen that is created by a service provider to guide broadcast programs, advertise various events, or deliver commercials is transmitted by the transmitting apparatus 201 using an idle band of the broadcasting channels 204 to 209.

[72] Here, the transmitting apparatus 201 transmits an SDTT, which is a component of a service information table, in addition to the channel change screen, thereby informing that the channel change screen is being transmitted to the recipient's terminal 203 (Step SOOl).

[73] The satellite 202 receives the channel change screen and the SDTT transmitted by the transmitting apparatus 201, and then transmits the received channel change screen and SDTT to the terminal 203 on the ground.

[74] In an idle state where power is turned on, the terminal 203 wakes up at a predetermined cycle and at a reserved time recorded in a transmission reservation table, and checks whether or not an SDTT of the service information table is detected (Step S002). Here, the terminal 203 previously receives and stores the transmission reservation table that indicates the time when the channel change screen is to be transmitted.

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

[76] The terminal 203 stores the channel change screen data in a temporary storage device until completely receiving the channel change screen data (Step S004).

[77] When completely receiving the channel change screen data, the terminal 203 searches a storage device for channel change screens of the terminal. When existing channel change screen data exists, the terminal 203 overwrites the newly received channel change screen data in the existing channel change screen data so as to store the new channel change screen data. When there is no existing channel change screen data, the terminal 203 stores the received channel change screen data (Steps S005 to S007).

[78] The recipient can watch various channels provided by the digital broadcasting using the terminal 203. When the recipient selects a broadcasting channel to watch or the recipient selects a different broadcasting channel while watching one broadcasting channel, as shown in (a) of FIG. 4 (Step S008), the terminal 203 displays the newly stored channel change screen (see (b) of FIG. 4) on the display device of the terminal 203 during the channel change time until the terminal 203 loads broadcasting data of the broadcasting channel selected by the recipient and plays the loaded broadcasting data (Step S009).

[79] Here, the channel change screen data stored in the terminal 203 may be a set of data on images or moving pictures regarding a plurality of channel change screens. Different channel change screens may be displayed according to channels, or different channel change screens may be displayed when a video channel is changed into an audio channel or when an audio channel is changed in a video channel. Alternatively, different channel change screens may be displayed according to time slots.

[80] According to the embodiments of the present invention, as a service of providing various channel change screens is provided during a channel change time, it is possible to positively and effectively advertise broadcast programs and deliver various events and commercials through the channel change screens during the channel change time, thereby increasing the effect of advertisement and public relation. In addition, convenience is provided such that a viewer does not feel a sense of boring, thereby improving service quality.

Claims

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

[2] The digital broadcasting system as set forth in claim 1, wherein the channel change screen 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 channel change screen 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 channel change screen 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 channel change screen data and stores the generated channel change screen data in the storage unit.

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

[7] The digital broadcasting system as set forth in claim 6, further comprising: a multiplexer that converts the channel change screen 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] A digital broadcasting method comprising the steps of: storing channel change screen data in a storage unit; causing a data broadcasting server to read the channel change screen data from the storage unit and to output the read channel change screen data according to a prescribed schedule; causing a PSI/SI server to receive the channel change screen 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 channel change screen data; and causing a transmitter to transmit the program specific information table and the service information table and to transmit the channel change screen data in an idle band of a broadcasting channel.

[10] The digital broadcasting method as set forth in claim 9, wherein the channel change screen includes at least one of a moving picture, an image, and an image sequence.

[11] The digital broadcasting method as set forth in claim 9, wherein the channel change screen is transmitted using an idle band of an EPG (Electronic Program Guide) channel, which transmits program guide information, among broadcasting channels.

[12] The digital broadcasting method as set forth in claim 9, wherein the channel change screen data is transmitted in an idle band that is generated when there is no broadcasting.

[13] The digital broadcasting method as set forth in claim 9, wherein a plurality of channel change screens are generated and transmitted to be separately used according to channels or time slots.

[14] The digital broadcasting method as set forth in claim 9, wherein the step of causing the transmitter to transmit the channel change screen data further includes a step of causing an encoder to encode the channel change screen data received from the data broadcasting server, and the transmitter transmits the encoded channel change screen data.

[15] The digital broadcasting method as set forth in claim 14, wherein the step of causing the transmitter to transmit the channel change screen data further includes a step of causing a multiplexer to multiplex the encoded channel change screen data, the program specific information table, and the service information table into a transport stream so as to output the multiplexed transport stream, and the transmitter transmits the multiplexed transport stream. [16] 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 to receive an SDTT; causing the terminal to recognize and receive channel change screen data with reference to the received SDTT; and causing, when a recipient selects a broadcasting channel, the terminal to display the received channel change screen on a display device of the terminal during a channel change time until the terminal loads broadcasting data of the selected channel and plays the loaded broadcasting data. [17] The digital broadcasting method as set forth in claim 16, wherein the channel change screen data includes a plurality of channel change screens, and the terminal displays different channel change screens according to channels or time slots.