JP2008177836A - Content transmission system, information providing device, and mobile terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow an information providing source for local contents to perform local information distribution services to a mobile terminal device which can view and listen to mobile broadcasting. <P>SOLUTION: The information providing source for local contents transmits a local content in frequency bands different from mobile broadcasting, although the source uses the same moving video and audio compression coding scheme, the same transmission format, and the same modulation scheme as mobile broadcasting. The mobile terminal device comprises a means for receiving even signals in different frequency bands from mobile broadcasting. Thereby, a user of the device can view and listen to a locally distributed content by a process the same as that of mobile broadcasting. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a content transmission system, an information providing device, and a mobile terminal device in which a local content information provider transmits content to a mobile terminal device. In particular, the local content information provider performs mobile broadcasting. The present invention relates to a content transmission system, an information providing apparatus, and a mobile terminal apparatus that provide a local information distribution service to a viewable mobile terminal apparatus.

  At present, mobile terminal devices having a communication function, such as mobile phones, are widely used. For example, most people traveling on street corners carry some kind of mobile terminal device. In addition, many mobile terminal devices are equipped with liquid crystal displays, and the communication method has shifted from analog to digital. In addition to text-based information communication, multimedia content such as voice and images is also available. Expansion of mobile communication services such as communication is expected.

  Under such a background, there is a need to broadcast or distribute moving image information specialized for the location to a mobile phone in a limited local location. For example, various information provision services such as various guide information in public spaces such as stations and airports, information on exhibitions and exhibitions at museums and museums, and special sale information at department stores and supermarkets, especially information provided by video content Service is conceivable. It is also conceivable to provide information to in-vehicle terminals by drive-in or drive-through.

  FIG. 9 shows a configuration example of an information distribution system that distributes information to a mobile phone. In the figure, reference numeral 100 is a mobile phone with a one-segment receiving function, reference numeral 600 is a broadcasting station, reference numeral 601 is an antenna of the broadcasting station, reference numeral 602 is a mobile phone base station, reference numeral 603 is a mobile telephone network, reference numeral Reference numeral 604 denotes an Internet network, and reference numeral 605 denotes a server.

  In the illustrated information distribution system, information can be distributed to the mobile phone by two kinds of information distribution methods.

  One is an information distribution method using the Internet network 604. That is, the user uses the mobile phone 100 to access the Internet network 604 via the mobile phone base station 602 and the mobile phone network 603, and acquires information from the server 605 in which the target information is stored. .

  For example, a proposal has been made for a system for providing regional information that can easily use regional information regarding a region when moving in an arbitrary region (see, for example, Patent Document 1). In this system, the terminal T retrieves and acquires area information about a required area from the area information database site S2 in which the area information is accumulated via the Internet C, and the acquired area information about the acquired area. Is transmitted to the e-mail site S3 together with the e-mail address of the portable information terminal E carried in the area and stored. Accordingly, it is possible to receive the area information stored in the e-mail site S3 by the portable information terminal E carried in the required area and display the image on the display unit of the portable information terminal E.

  Local content distribution methods using the Internet network 604 can be broadly classified into pull-type distribution in which information is received by a user operation from the mobile phone 603 side and push-type distribution using e-mail or the like. However, in any distribution mode, there is a problem that it is difficult to view moving image content on a mobile phone at the transmission speed of the mobile phone.

  The other is a method of distributing information in a broadcast form by a digital mobile broadcast service represented by One Seg. In this case, the content of the broadcasting station 600 is broadcast by the antenna 601.

  Here, One Seg is a digital mobile broadcast that was started on Saturday, April 1, 2006 in Japan, and is the middle of 13 segments divided from the 6 MHz band used in terrestrial digital TV broadcasts. A reception service in which one segment portion is allocated to reception for a mobile terminal device such as a mobile phone is performed (for example, see Non-Patent Document 1). Incidentally, high-definition (HDTV) broadcasting for fixed reception is organized using other 12 segments. According to 1Seg, video, audio, and data can be obtained with only one segment, and television broadcasting can be viewed on a mobile terminal device with low power consumption and simple information processing.

  For example, a 13-segment receiver that selects and demodulates a desired signal from a received signal, a 1-segment receiver, and a signal path selector that has a signal path that selectively outputs an output signal from one of the receivers. The reception state of the received signal is monitored and determined, and if it is determined that the reception state falls below a predetermined reference value, the signal path is switched so that the output signal from the one-segment receiver is output. Proposals have been made on a television reception system for digital terrestrial broadcasting that is configured (see, for example, Patent Document 2).

  However, broadcasting is basically a system specialized in distributing the same content to many users in a wide area, and does not originally have a mission to distribute local content. In other words, the 1Seg program service has the same content as a normal TV receiver program that uses 12 segments, and various guide information in public spaces such as stations and airports, or exhibitions and events in museums and museums. It is not supposed to be a local information distribution service such as guidance, information on special sales at department stores and supermarkets. For example, a terrestrial digital broadcasting base station apparatus that performs area-limited broadcasting has been proposed (see, for example, Patent Document 3). Local broadcasting here uses the same frequency band as the one-segment broadcasting service. Therefore, only broadcasters with licenses can implement it.

JP 2001-67296 A JP 2006-310948 A JP 2006-279376 A http: // www. d-pa. org

  An object of the present invention is to provide an excellent content transmission system, an information providing apparatus, and a mobile terminal device that can suitably transmit content to a mobile terminal device by an information provider of local content. .

  A further object of the present invention is to provide an excellent content transmission system and information providing apparatus capable of suitably providing a local information distribution service to a mobile terminal device from which a local content information provider can view mobile broadcasts. It is another object of the present invention to provide a mobile terminal device.

The present invention has been made in consideration of the above problems, and is a content transmission system that provides a local broadcast content reception service in an environment where mobile broadcasting is provided,
Provision of information for transmitting a local broadcast composed of local content in a frequency band different from that of the mobile broadcast, using the same moving image or audio compression encoding method, the same transmission format, and the same modulation method as the mobile broadcast. Original and
A mobile terminal device for receiving and viewing the mobile broadcast, receiving local broadcast content transmitted in a frequency band different from the mobile broadcast, and decoding and demodulating the local broadcast content in the same process as the mobile broadcast;
It is a content transmission system characterized by comprising.

  However, “system” here refers to a logical collection of a plurality of devices (or functional modules that realize specific functions), and each device or functional module is in a single housing. It does not matter whether or not (hereinafter the same).

  At present, mobile terminal devices having a communication function, such as mobile phones, are widely used. Under these circumstances, the present inventors consider that an information distribution service in which a local content information provider transmits content to a mobile terminal device is useful in a limited local location such as a public space. ing.

  In order to distribute information to mobile phones, there are a distribution form using the Internet and a broadcast-type distribution form depending on a receiving service such as One Seg. However, in the former case, it is difficult to view moving image content on a mobile phone at the transmission speed of the mobile phone. In the latter case, broadcasting is basically a system specialized in delivering the same content to many users in a wide area, and is not intended for a local information delivery service.

  On the other hand, the content transmission system according to the present invention includes a local content information provider and a mobile terminal device capable of viewing mobile broadcasts. The information provider is the same video and audio as mobile broadcasts. However, local content is transmitted in a frequency band different from that of mobile broadcasting, although the same compression encoding method, the same transmission format, and the same modulation method are used. The mobile terminal device is provided with a means for receiving even in a frequency band different from that of mobile broadcast, and is configured to view content distributed locally by a process similar to mobile broadcast. For example, the information provider can carry out local broadcasting services arbitrarily by anyone, not limited to a specific broadcaster, by transmitting local content using a frequency band that does not require a license, such as the 2.4 GHz band. Can do.

  Therefore, in the content transmission system according to the present invention, the same moving image, audio compression encoding method, the same transmission format, and the same modulation method as those of the one-segment broadcasting are used. It is possible to make a mobile phone that can receive both.

  The information provider encodes and compresses a plurality of local broadcast contents including video, audio, and data broadcast contents using the same compression encoding method as the mobile broadcast and generates a stream that is multiplexed using the same transmission format. A multiplexing processing unit that performs multi-carrier modulation on the generated stream signal using the same modulation scheme as that of the mobile broadcast, and up-converts the multi-carrier transmission signal to a frequency band different from that of the mobile broadcast. And a transmitting unit for transmitting the up-converted broadcast signal.

  Then, the mobile terminal apparatus performs demodulation processing, error correction processing, video, audio, and data multiplexed signal restoration processing, image processing, audio processing, and data processing for content signals received in a frequency band different from mobile broadcasting. , Operate with the same hardware and software as when receiving mobile broadcasts.

  The mobile terminal device includes a frequency converter that performs frequency conversion from the frequency band to a frequency band used in mobile broadcasting as means for receiving even in a frequency band different from mobile broadcasting. After the frequency conversion, the local broadcast content can be viewed using the same process as that for mobile broadcasting.

  Specifically, the mobile terminal device is different from the mobile broadcast band, the mobile broadcast receiving antenna, a first down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal, and A local content broadcast receiving antenna distributed in a frequency band, a second down converter for converting a received signal from the local content broadcast receiving antenna into a frequency in the vicinity of a mobile broadcast band, and the first down converter Demodulation / decoding means for demodulating and decoding the intermediate frequency signal output from the signal, and output means for externally outputting image information or audio information obtained by the demodulation / decoding means. Depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the first down converter is either the antenna for receiving the mobile broadcast or the output of the second down converter. It is configured to switch.

  Alternatively, the mobile terminal device includes a receiver capable of receiving a radio signal in the frequency band as means for receiving in a frequency band different from that of the mobile broadcast, and is configured to be able to view both the mobile broadcast and the local broadcast. You can also

  Specifically, the mobile terminal device is different from the mobile broadcast band, the mobile broadcast receiving antenna, a first down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal, and A local content broadcast receiving antenna distributed in a frequency band, a second down converter for converting a received signal from the local content broadcast receiving antenna into the intermediate frequency signal, and demodulating and decoding the intermediate frequency signal Demodulation / decoding means and output means for outputting image information or audio information obtained by the demodulation / decoding means to the outside. Depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the demodulation / decoding means is either the output of the first down converter or the output of the second down converter. Configured to switch to

  Alternatively, when the mobile terminal device is equipped with a wireless LAN function, as a means for receiving even in a frequency band different from that of mobile broadcast, the built-in wireless LAN receiving unit is used in common, and mobile broadcast and local broadcast Can be configured to be able to be viewed.

  Specifically, the mobile terminal device includes the mobile broadcast receiving antenna, a down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal, and a frequency band different from the mobile broadcast band. A wireless LAN antenna capable of transmitting and receiving wireless LAN signals and receiving local content broadcasts distributed in the frequency band, a baseband processing unit for wireless LAN, and a transmission unit for upconverting transmission baseband signals And a receiving unit that down-converts a received signal from the wireless LAN antenna into a baseband, a demodulation / decoding unit that demodulates and decodes the intermediate frequency signal and the baseband signal, and a demodulation / decoding unit Output means for outputting image information or audio information externally is provided. Then, depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the demodulation / decoding means is an intermediate frequency signal output from the down converter or a baseband output of the reception unit. It is configured to switch to either.

  Regardless of the configuration of means for receiving in a frequency band different from that of mobile broadcast, mobile broadcast and local content broadcast can be arbitrarily switched via a user operation unit or the like. Therefore, the user carrying the mobile terminal device can alternatively view the favorite one of the mobile broadcast and the local content depending on the situation when entering the service area of the local broadcast. .

  Here, local broadcasting is a service in a limited area within a radius of 100 m, for example, and there is a problem that the user does not know where to receive the service. Therefore, a notification means for notifying the mobile terminal device that it is within the service area of the local broadcast may be further provided.

  A local broadcast distributed from an information provider of local content is composed of, for example, a plurality of channels obtained by segmenting an OFDM modulated signal. In such a case, at least one segment is allocated to the control channel, and detailed information such as the service ID and service name of the local broadcast, the broadcast station ID, the total number of channels, the program ID, and the presence or absence of encryption is notified. The service area can be notified to the mobile terminal device.

  On the other hand, a mobile terminal device such as a mobile phone searches a control channel for local broadcasting while intermittently receiving a paging signal from a mobile phone base station. When this control channel is detected, the user is notified of the fact that it has entered the local broadcast service area using means such as an alarm.

  For example, the local broadcast content signal may be scrambled. The mobile terminal device accesses the Internet via a mobile phone network or a wireless LAN network, notifies a user ID, a password, a broadcast station ID, a program ID, etc. to an information provider server, passes through an authentication process, and then scrambles・ Obtain a key and start viewing a local broadcast.

  ADVANTAGE OF THE INVENTION According to this invention, the outstanding content transmission system, information provision apparatus, and mobile terminal device which the information provider of local content can transmit a content suitably to a mobile terminal device can be provided. .

  Further, according to the present invention, an excellent content transmission system and information provision capable of suitably providing a local information distribution service to a mobile terminal device capable of viewing mobile broadcasts by a local content information provider An apparatus and a mobile terminal device can be provided.

  In the content transmission system according to the present invention, since the same moving image, audio compression encoding method, the same transmission format, and the same modulation method as those of the one-segment broadcasting are used, both local content reception and mobile broadcasting can be performed at low cost. It is possible to make a mobile phone that can receive the message.

  Further, in the content transmission system according to the present invention, a local broadcast wave is transmitted with a weak power using a frequency band different from the broadcast wave, so that a local content information providing service with a limited information providing area can be realized. . For example, the information provider can carry out local broadcasting services arbitrarily by anyone, not limited to a specific broadcaster, by transmitting local content using a frequency band that does not require a license, such as the 2.4 GHz band. Can do.

  Further, according to the content transmission system of the present invention, it is possible to realize a viewing mode in which a mobile phone automatically recognizes that a user has entered a local broadcast service area and starts receiving the broadcast. it can.

  Other objects, features, and advantages of the present invention will become apparent from more detailed description based on embodiments of the present invention described later and the accompanying drawings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  At present, mobile terminal devices having a communication function, such as mobile phones, are widely used. Under such circumstances, an information distribution service in which a local content information provider transmits content to a mobile terminal device in a local limited place such as a public space is useful.

  In the content transmission system according to the present invention, an information provider responsible for the local broadcasting business uses the same video and audio compression and coding system as that of digital mobile broadcasting for a mobile phone and uses the same transmission format for digital transmission.・ Local content is distributed in a frequency band different from mobile broadcasting. On the other hand, a cellular phone with a digital mobile broadcast receiver receives content transmission waves and views local content. In the following description, an information provider of local content transmits local broadcast content using a 2.4 GHz band that is open to a system that directly uses radio wave energy, called an ISM (Industry Science and Medical) band. Shall.

  From December 1, 2003, the terrestrial digital TV broadcasting service ISDB-T (Integrated Services Digital) using the terrestrial UHF (Ultra High Frequency) band (470 MHz to 770 MHz) in the three large areas of Kanto, Kinki and Chukyo. (Broadcasting foot Terrestrial) has started, but 1Seg allocates one middle segment of 13 segments divided from the 6MHz band used in digital terrestrial TV broadcasting to reception for mobile terminal devices such as mobile phones. Digital mobile broadcasting service. Incidentally, high-definition (HDTV) broadcasting for fixed reception is organized using other 12 segments.

  One seg is a reception service using only one segment having a bandwidth of 492 kHz, and a band of 440 to 770 MHz is used for one seg. In addition, the video transmitted in one segment is QVGA (Quarter Video Graphic Array: 320 × 240 pixels). H.264 / MPEG-4AVC is used. According to 1Seg, video, audio, and data can be obtained with only one segment, and television broadcasting can be viewed on a mobile terminal device with low power consumption and simple information processing.

  In this type of digital broadcasting, an OFDM (Orthogonal Frequency Division Multiplexing) modulation system is usually employed. In the OFDM modulation scheme, the frequency of each carrier is set so that each subcarrier is orthogonal to each other within a symbol interval, and transmission data is distributed and transmitted to a plurality of carriers having different frequencies. The band becomes narrow and the frequency utilization efficiency becomes very high. In addition, it is resistant to reception environments such as fading and multipath interference caused by reflection from buildings.

  FIG. 1 shows a configuration example of a mobile phone 100 equipped with a one-segment broadcasting reception function.

  In the figure, reference numeral 101 is a one-segment broadcast receiving antenna, reference numeral 102 is a down converter, reference numeral 103 is a low noise amplifier (LNA), reference numeral 104 is a mixer, reference numeral 105 is a local oscillator, and reference numeral 106 is AGC. (Auto Gain Control: automatic gain control) amplifier. Reference numeral 107 is an OFDM demodulator, reference numeral 108 is a reconstruction processing unit for a multiplexed signal of a transport stream to be broadcast, reference numeral 109 is a mobile phone block, and includes a CPU 110. Reference numeral 111 is a mobile phone antenna, reference numeral 112 is an audio processing unit, reference numeral 113 is a speaker, reference numeral 114 is an image processing unit, reference numeral 115 is a liquid crystal display, and reference numeral 116 is an operation unit.

The down converter 102 includes an LNA 103, a mixer 104, a local oscillator 105, and an AGC amplifier 106. A broadcast wave (see FIG. 9) transmitted from the broadcast station 600 through the antenna 601 is received by the one-segment broadcast receiving antenna 101 of the mobile phone 100, amplified by the LNA 103, and then the local oscillator 105 by the mixer 104. It is mixed with the frequency, is converted to an intermediate frequency (intermediate frequency) F _i. F _i is generally about 1MHz is used. The reception frequency is determined by the local frequency oscillated by the local oscillator 105. The gain of the AGC amplifier 106 is automatically controlled so that the intermediate frequency F _i becomes a constant level.

  The broadcast signal converted into the intermediate frequency signal is demodulated by the OFDM demodulator 107. At this time, error correction is also performed using a Viterbi code and a Reed-Solomon code added to the signal. The demodulated data is a transport stream (TS).

  Here, as a method for multiplexing individual streams such as encoded video, audio, and additional data and reproducing them while synchronizing them, there are two types, PS (Program Stream) and TS (Transport Stream). There is a method. PS is assumed to be applied to data transmission and storage in an error-free environment, and since it can reduce redundancy, it is used in digital storage media using powerful error correction codes. ing. On the other hand, TS is adopted as a multiplexed signal for digital broadcasting, assuming application to an environment in which data transmission errors occur, such as broadcasting and communication networks. A major feature of TS is that individual streams such as video, audio, and data are handled in a common signal format regardless of the type of application or transmission path, and multiple programs are configured and transmitted within a single stream. It is in that it can be done.

  The multiplexed signal restoration processing unit 108 extracts target video, audio, and data from the demodulated transport stream in accordance with an instruction from the CPU 110 in the mobile phone block 109. The sound is decoded into an analog signal by the sound processing unit 112 and output as sound from the speaker 113. The moving image and data are decoded by the image processing unit 114 and displayed on the liquid crystal display unit 115. In this way, it is possible to view the one-segment broadcast on the mobile phone 100.

  On the other hand, an antenna 111 is connected to the mobile phone block 109 to communicate with a mobile phone base station. An operation unit / microphone unit 116 is also connected. Since the cellular phone function itself is not directly related to the gist of the present invention, detailed description thereof is omitted in this specification.

  In the content transmission system according to the present invention, the same moving image, audio compression and coding scheme, the same transmission format and the same modulation scheme as those of mobile broadcasting such as one-segment broadcasting are used, but local broadcasting content in a frequency band different from mobile broadcasting. Is sent. In order to enjoy this type of reception service on the mobile phone side, it is equipped with a 1seg broadcast reception function and has means for receiving even in a frequency band different from mobile broadcast, and is distributed locally by the same process as mobile broadcast Configured to view content. By providing local content using a frequency band that does not require a license, such as the 2.4 GHz band, the information provider can arbitrarily implement a local broadcast service, not limited to a specific broadcaster. Please note that.

  FIG. 2 shows a configuration example of a mobile phone 100 that is equipped with a one-segment broadcasting reception function and that can receive local broadcasting content by including means for receiving even in a frequency band different from mobile broadcasting.

The illustrated mobile phone 100 includes a down converter that converts a frequency from the 2.4 GHz band to a frequency in the vicinity of the one segment broadcast band. In the figure, reference numeral 201 is a 2.4 GHz band antenna, and reference numeral 202 is a down converter. The down converter 202 includes an LNA 203, a mixer 204, and a local oscillator 205. When a signal including local content transmitted in the 2.4 GHz band described later is received by the antenna 201 for local broadcast reception, the signal is amplified by the LNA 203, and the frequency of the local oscillator 205 and the mixer are used in the vicinity of the one-segment broadcast band. It is converted to the frequency F _b. If this frequency is the same as the actual broadcast frequency, there is a possibility of interference, so a slightly shifted frequency is set. Naturally, the local oscillator 106 at this time is also reset so that F _b can be received.

On the other hand, the down-converter 102 for receiving one-segment broadcasting includes an LNA 103, a mixer 104, a local oscillator 105, and an AGC amplifier 106. A broadcast wave (see FIG. 9) transmitted from the broadcast station 600 through the antenna 601 is received by the one-segment broadcast receiving antenna 101 of the mobile phone 100, amplified by the LNA 103, and then the local oscillator 105 by the mixer 104. And is converted to an intermediate frequency F _i . In addition, when the signal converted from the 2.4 GHz band to the frequency near the one-segment broadcasting band by the down converter 202 is also input to the down converter 102 via the switch 206, the signal is similarly amplified by the LNA 103. The frequency is mixed with the frequency of the local oscillator 105 by the mixer 104 and converted to the intermediate frequency F _i . The reception frequency is determined by the local frequency oscillated by the local oscillator 105. The gain of the AGC amplifier 106 is automatically controlled so that the intermediate frequency F _i becomes a constant level.

  After down converter 102, switch 206 switches whether to receive a broadcast wave from antenna 101 for receiving one-segment broadcast or to receive a local broadcast wave in the 2.4 GHz band. This switch switching is performed according to an instruction from the CPU 110. In the local broadcast reception mode, the switch 206 can select the A side in the figure and receive the local broadcast wave from the antenna 201. On the other hand, when receiving one-segment broadcasting, the switch 206 selects the B side in the figure.

  The broadcast signal converted into the intermediate frequency signal is demodulated by the OFDM demodulator 107. At this time, error correction is also performed using a Viterbi code and a Reed-Solomon code added to the signal. The demodulated data is a transport stream (TS).

  The multiplexed signal restoration processing unit 108 extracts target video, audio, and data from the demodulated transport stream in accordance with an instruction from the CPU 110 in the mobile phone block 109. The sound is decoded into an analog signal by the sound processing unit 112 and output as sound from the speaker 113. The moving image and data are decoded by the image processing unit 114 and displayed on the liquid crystal display unit 115. In this way, it is possible to view the one-segment broadcast on the mobile phone 100.

  On the other hand, an antenna 111 is connected to the mobile phone block 109 to communicate with a mobile phone base station. An operation unit / microphone unit 116 is also connected.

  FIG. 3 shows another configuration example of the mobile phone 100 that is equipped with a one-seg broadcast reception function and that can receive local broadcast content by including means for receiving even in a frequency band different from mobile broadcast.

The cellular phone shown in the figure includes a down converter 301 for converting from the 2.4 GHz band to the same intermediate frequency F _i as when receiving one segment. In the figure, reference numeral 201 is a 2.4 GHz band antenna, and the down converter 301 includes an LNA 203, a mixer 302, and a local oscillator 303. When a signal including local content transmitted in the 2.4 GHz band, which will be described later, is received by the antenna 201, it is amplified by the LNA 203, mixed with the local frequency oscillated by the local oscillator 303 by the mixer 302, and the intermediate frequency F _i. Is converted to The AGC amplifier 304 is controlled so that the IF frequency becomes a constant level.

On the other hand, the down converter 102 includes an LNA 103, a mixer 104, a local oscillator 105, and an AGC amplifier 106. A broadcast wave (see FIG. 9) transmitted from the broadcast station 600 through the antenna 601 is received by the one-segment broadcast receiving antenna 101 of the mobile phone 100, amplified by the LNA 103, and then the local oscillator 105 by the mixer 104. And is converted to an intermediate frequency F _i . The gain of the AGC amplifier 106 is automatically controlled so that the intermediate frequency F _i becomes a constant level.

  Whether to receive a broadcast wave from the antenna 101 for receiving one-segment broadcast or to receive a local broadcast wave in the 2.4 GHz band from the antenna 201 is switched by the switch 305. This switch switching is performed according to an instruction from the CPU 110. In the local broadcast reception mode, the switch 305 can select the C side in the figure and receive the local broadcast wave from the antenna 201. Further, when receiving the one-segment broadcast, the switch 305 selects the D side in the figure.

  The broadcast signal converted into the intermediate frequency signal is demodulated by the OFDM demodulator 107. At this time, error correction is also performed using a Viterbi code and a Reed-Solomon code added to the signal. The demodulated data is a transport stream (TS).

  The multiplexed signal restoration processing unit 108 extracts target video, audio, and data from the demodulated transport stream in accordance with an instruction from the CPU 110 in the mobile phone block 109. The sound is decoded into an analog signal by the sound processing unit 112 and output as sound from the speaker 113. The moving image and data are decoded by the image processing unit 114 and displayed on the liquid crystal display unit 115. In this way, it is possible to view the one-segment broadcast on the mobile phone 100.

  On the other hand, an antenna 111 is connected to the mobile phone block 109 to communicate with a mobile phone base station. An operation unit / microphone unit 116 is also connected.

  In addition, recent mobile phones include models equipped with wireless LAN and IP phone functions. FIG. 4 shows a configuration example of a cellular phone 100 that is equipped with a one-segment broadcasting reception function and that realizes viewing of local broadcast contents by using a 2.4 GHz band wireless LAN receiver as a local broadcast receiving means. ing.

  In the figure, reference numeral 401 is an antenna switch for switching between transmission and reception, reference numeral 402 is a wireless LAN transmitter, and reference numeral 403 is a wireless LAN receiver. A baseband processing unit indicated by reference numeral 405 performs wireless LAN modulation / demodulation processing and protocol control processing. The baseband processing unit 205 is connected to the mobile phone block 110, and performs various controls and transmission / reception data transmission / reception.

On the other hand, the down converter 102 includes an LNA 103, a mixer 104, a local oscillator 105, and an AGC amplifier 106. A broadcast wave (see FIG. 9) transmitted from the broadcast station 600 through the antenna 601 is received by the one-segment broadcast receiving antenna 101 of the mobile phone 100, amplified by the LNA 103, and then the local oscillator 105 by the mixer 104. And is converted to an intermediate frequency F _i . The gain of the AGC amplifier 106 is automatically controlled so that the intermediate frequency F _i becomes a constant level.

  The switch 404 switches whether to receive a local broadcast wave in the 2.4 GHz band or to use it as a wireless LAN. In the case of receiving a local broadcast wave, the switch 305 selects the E side in the figure and passes the baseband IQ signal to the OFDM demodulator 107. Which demodulation is performed is instructed by the CPU 110. When receiving a 2.4 GHz band local broadcast wave, the OFDM demodulator 107 demodulates OFDM from the IQ signal, not from the IF signal. On the other hand, when a normal wireless LAN is used, the switch 404 selects the F side in the figure and transfers the baseband IQ signal to the baseband processing unit 405.

  The broadcast signal after OFDM demodulation is also subjected to error correction using a Viterbi code and a Reed-Solomon code added to the signal. The demodulated data is a transport stream (TS).

  The multiplexed signal restoration processing unit 108 extracts target video, audio, and data from the demodulated transport stream in accordance with an instruction from the CPU 110 in the mobile phone block 109. The sound is decoded into an analog signal by the sound processing unit 112 and output as sound from the speaker 113. The moving image and data are decoded by the image processing unit 114 and displayed on the liquid crystal display unit 115. In this way, it is possible to view the one-segment broadcast on the mobile phone 100.

  On the other hand, an antenna 111 is connected to the mobile phone block 109 to communicate with a mobile phone base station. An operation unit / microphone unit 116 is also connected.

  Until now, the content transmission system according to the present invention has been described with a focus on the configuration of a mobile phone capable of receiving and viewing local broadcast content. Below, it explains in detail about transmission equipment of local broadcast contents.

  FIG. 5 shows a configuration example of a local content broadcast distribution system. Since the mechanisms of the mobile broadcast system and the mobile phone system are the same as the system shown in FIG. 9, the description thereof is omitted. The broadcast distribution system shown in the figure is mainly characterized in that a 2.4 GHz band transmitter 500 and a content server 502 are equipped for local content broadcasting. Since the information provider transmits local content using a frequency band that does not require a license, such as a 2.4 GHz band, anyone can arbitrarily implement a local broadcast service, not limited to a specific broadcaster.

  In addition to video and audio content, content server 502 stores content described in a page description language for data broadcasting based on XML (Extensible Markup Language) called BML (Broadcast Markup Language) for data broadcasting. Has been.

  The transmitter 500 includes a multiprocessing unit 503 that generates a transport stream from the content of the content server 502, an OFDM modulation unit 504 that adds OFDM modulation and an error correction code, a transmission unit 505, and a 2.4 GHz band A local oscillator 506 and an antenna 507 are included. A local broadcast wave of 2.4 GHz band is transmitted from the antenna 507. On the frequency axis, as shown in the balloon of reference number 510, it is possible to configure a channel every 429 KHz. The mobile phone 100 receives the desired local broadcast wave, further demodulates it, restores data, and outputs video and audio.

  When paying for local broadcasting, encryption such as scramble is required. The multiprocessing unit 503 scrambles using the designated scramble key 508 from the content server 502. Of course, the content server 502 may be scrambled.

  In such a case, there is a method of using the mobile phone network 603 as means for passing the scramble key 508 to the mobile phone 100. First, the content server 502 is accessed via the base station 602, the mobile phone network 603, and the Internet network 604 from the mobile phone 100, and a scramble key 508 is obtained through a subscription and authentication procedure.

  Another method for passing the scramble key to the mobile phone 100 is to use a wireless LAN function. If the mobile phone 100 has a built-in wireless LAN function, a wireless LAN access point 509 can be installed and the scramble key 508 can be distributed via the wireless LAN access point 509.

  On the mobile phone 100 side, the scramble key is notified from the CPU 110 by the multiple signal restoration processing unit 108, and descrambling is performed.

  Here, the local broadcast is a service in a limited area within a radius of 100 m, for example. For this reason, there is a problem that the user does not know where the service can be received. Therefore, there is a need for means for automatically informing the user that the service area has been entered. Hereinafter, a method for notifying the user that the user has entered the local broadcast service area will be described.

  Local broadcasting is composed of a plurality of channels obtained by segmenting OFDM modulation signals, and a control channel is provided for one segment among them. Then, detailed information including at least one of the service ID, the service name, the broadcast station ID, the total channel number, the program ID, and the presence / absence of encryption on the local broadcast is reported on the control channel.

  On the other hand, the mobile phone 100 searches for a control channel for local broadcasting while intermittently receiving a paging signal from the mobile phone base station. When a local broadcast control channel is detected, the user is notified of the fact that the user has entered the local broadcast service area using means such as an alarm.

  FIG. 6 shows a configuration example of a control signal for local broadcasting. In the figure, reference numeral 701 is a control signal assigned to one channel obtained by segmenting an OFDM signal, and has the same band of 429 KHz as in one-segment broadcasting. Similarly, the local broadcast content signal 702 is assigned to CH1 to CHn for each band of 429 KHz.

  The control channel includes information such as service ID 703, service name 704, broadcast station ID 705, total number of channels 706 (= n), channel information 707, and the like. The channel information 707 includes a program ID, program information, a pay / free flag, etc. for each channel.

  These pieces of broadcast information are sent separated by 188 bytes of TS packets used in digital broadcasting. A header such as service ID 703 is added to the first packet, but when the number of channels is large, only the channel information is transmitted on the subsequent packet. In this way, the control signal 701 is repeatedly and continuously notified.

  A method of detecting a local broadcast control signal on the mobile phone 100 side will be described with reference to FIG.

In the figure, reference numeral 801 is a paging signal from the mobile phone base station 602, it is transmitted at intervals of a predetermined period T _b. When there is an incoming call to the mobile phone 100, the mobile phone base station 602 notifies this with the paging signal 801. In the illustrated example, the mobile phone 100 performs intermittent reception of the paging signal 801 in the time zone indicated by reference numeral 803 and waits for an incoming call to the own station.

  On the other hand, the local broadcast station continuously broadcasts a control signal indicated by reference numeral 802 using one segmented channel. The mobile phone 100 searches for the control signal 802 immediately after the intermittent reception of the paging signal at the timing indicated by reference numeral 803. As a search method, first, the presence or absence of a carrier is confirmed, and when the carrier can be confirmed, a service ID is detected.

  By carrying out intermittent reception in this manner, the mobile phone 100 can check whether or not the local broadcast is at the place, and can reduce the power consumption burden during standby.

  This search mode does not need to be always on, and if the user can switch on / off, power consumption due to unnecessary search can be avoided.

  FIG. 8 shows an operation sequence until the mobile phone 100 views a local broadcast by intermittent reception.

8-1: A paging signal is transmitted from the mobile phone network. The cellular phone receives this paging signal intermittently and monitors the incoming call of its own station.

8-2: The local broadcasting station repeatedly and continuously notifies the control signal. The mobile phone receives this control signal intermittently and monitors whether it has entered the local broadcast area.

8-3: A control signal for local broadcasting is detected on the mobile phone side.

8-4: A message notifying that the mobile phone has entered the local broadcast area is displayed on the liquid crystal unit of the mobile phone.

8-5: The mobile phone receives the control signal and displays a list of contents of the local broadcast content on the liquid crystal unit. At this time, the charge / free classification of the content is also displayed.

8-6: On the mobile phone side, it is checked whether the content that the user wants to see is paid content. If it is free content, go to 8-12.

8-7: On the mobile phone side, a user ID and password input screen is displayed on the liquid crystal unit, and the user is requested to input.

8-8: Automatically connect to the mobile phone network.

8-9: A user ID, a password, a broadcast station ID, a program ID, and the like are transmitted to the broadcast station via the mobile phone network.

8-10: On the local broadcasting station side, authentication is performed using a user ID and a password.

8-11: The local broadcasting station transmits the scramble key of the program to the mobile phone via the mobile phone network.

8-12: The mobile phone side descrambles the transport stream signal of the local broadcast with the sent scramble key and enables viewing. Content that has not been scrambled can be viewed as it is.

  As described above, according to the present embodiment, the information provider uses the same moving image, audio compression encoding method, the same transmission format, and the same modulation method as those of the one-segment broadcasting, and the local content in the 2.4 GHz band. Send. Then, it is possible to easily view local contents on a mobile phone by simply providing a mobile phone equipped with a one-segment broadcasting reception function with a reception function for receiving the 2.4 GHz band. In addition, the user can automatically know that he / she has entered the local broadcast service area.

  The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiment without departing from the gist of the present invention. That is, the present invention has been disclosed in the form of exemplification, and the contents described in the present specification should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims should be taken into consideration.

FIG. 1 is a diagram showing a configuration example of a mobile phone 100 equipped with a one-segment broadcasting reception function. FIG. 2 is a diagram showing a configuration example of a mobile phone 100 that is equipped with a one-seg broadcast receiving function and that has means for receiving even in a frequency band different from that of mobile broadcast and can view local broadcast content. FIG. 3 is a diagram showing another configuration example of the mobile phone 100 that is equipped with a one-seg broadcast receiving function and has means for receiving even in a frequency band different from that of the mobile broadcast and can view the local broadcast content. FIG. 4 shows a configuration example of a mobile phone 100 that is equipped with a one-segment broadcasting reception function and that realizes viewing of local broadcasting content by using a 2.4 GHz band wireless LAN receiving unit as a purpose of receiving local broadcasting. It is a figure. FIG. 5 is a diagram showing a configuration example of a local content broadcast distribution system. FIG. 6 is a diagram illustrating a configuration example of a control signal for local broadcasting. FIG. 7 is a diagram for explaining an operation for detecting a control signal for local broadcasting on the mobile phone 100 side. FIG. 8 is a diagram showing an operation sequence until the mobile phone 100 views a local broadcast by intermittent reception. FIG. 9 is a diagram illustrating a configuration example of an information distribution system that distributes information to a mobile phone.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Mobile phone with one segment receiving function 101 ... One segment broadcast receiving antenna 102 ... Down converter 103 ... Low noise amplifier (LNA)
DESCRIPTION OF SYMBOLS 104 ... Mixer 105 ... Local oscillator 106 ... Automatic gain control (AGC) amplifier 107 ... OFDM demodulation part 108 ... Multiple signal restoration process part 109 ... Cell-phone block 110 ... CPU
DESCRIPTION OF SYMBOLS 111 ... Mobile phone antenna 112 ... Audio processing unit 113 ... Speaker 114 ... Image processing unit 115 ... Liquid crystal display 116 ... Operation unit 201 ... Local broadcast receiving antenna 202 ... Down converter 203 ... LNA
204 ... mixer 205 ... local oscillator 206 ... switch 301 ... down converter 302 ... mixer 303 ... local oscillator 304 ... AGC amplifier 305 ... switch 402 ... wireless LAN transmitter 403 ... wireless LAN receiver 404 ... switch 405 ... baseband processor 500 ... 2.4 GHz band transmitter 502 ... Content server 503 ... Multiplexing section 504 ... OFDM modulation section 505 ... Transmission section 506 ... Local oscillator 507 ... Local broadcast transmission antenna 509 ... Access point 600 ... Broadcast station 601 ... Antenna 602 ... Mobile phone base station 603 ... mobile phone network 604 ... internet network 605 ... server

Claims (16)

A content transmission system that provides a local broadcast content reception service in an environment where mobile broadcasting is provided,
Provision of information for transmitting a local broadcast composed of local content in a frequency band different from that of the mobile broadcast, using the same moving image or audio compression encoding method, the same transmission format, and the same modulation method as the mobile broadcast. Original and
A mobile terminal device for receiving and viewing the mobile broadcast, receiving local broadcast content transmitted in a frequency band different from the mobile broadcast, and decoding and demodulating the local broadcast content in the same process as the mobile broadcast;
A content transmission system comprising: The information provider encodes and compresses a plurality of local broadcast contents including video, audio, and data broadcast contents by the same compression encoding method as the mobile broadcast and multiplexes the streams by the same transmission format. A multiplexing processing unit to generate, a multicarrier modulation unit that multicarrier modulates the generated stream signal by the same modulation method as the mobile broadcast, and the multicarrier transmission signal to a frequency band different from that of the mobile broadcast A transmission unit for conversion, and an antenna for transmitting the up-converted broadcast signal,
The content transmission system according to claim 1. The information provider further comprises scramble key distribution means for scrambling the multiplexed stream and passing the scramble key to the mobile terminal device through a predetermined procedure,
In the mobile terminal device, the received stream is descrambled using a scramble key.
The content transmission system according to claim 2. The information provider further comprises notification means for notifying the mobile terminal device that it is within a service area of local broadcasting,
The content transmission system according to claim 1. The local broadcast is composed of a plurality of channels obtained by segmenting a multicarrier modulation signal, and a control channel is provided in at least one segment among them,
The information provider notifies the control channel of detailed information including at least one of a service ID, a service name, a broadcast station ID, a total channel number, a program ID, and presence / absence of encryption related to the local broadcast,
The mobile terminal device searches for a control channel for local broadcast, and notifies the user that it has entered the service area for local broadcast in response to detecting this control channel.
The content transmission system according to claim 1. An information providing apparatus that provides local broadcast content in an environment where mobile broadcast is provided,
Multiplexing processing unit that encodes and compresses a plurality of local broadcast contents including video, audio, and data broadcast contents by the same compression encoding method as that of the mobile broadcast and generates a multiplexed stream by the same transmission format When,
A modulation unit that modulates the generated stream signal by the same modulation method as the mobile broadcast;
A transmitter that up-converts the multicarrier transmission signal to a frequency band different from that of the mobile broadcast;
An antenna for transmitting the up-converted broadcast signal;
An information providing apparatus comprising: Scrambling means for scrambling the multiplexed stream;
A scramble key distribution means for passing a scramble key through a predetermined procedure to a recipient of the local broadcast content;
The information providing apparatus according to claim 6, further comprising: Further comprising notification means for notifying the mobile terminal device that it is within a service area of local broadcasting,
The information providing apparatus according to claim 6. The local broadcast is composed of a plurality of channels obtained by segmenting a multicarrier modulation signal, and a control channel is provided in at least one segment among them,
The notifying means notifies the control channel of detailed information including at least one of a service ID, a service name, a broadcast station ID, a total channel number, a program ID, and presence / absence of encryption related to the local broadcast;
The information providing apparatus according to claim 8. A mobile terminal device capable of viewing mobile broadcasts,
Means for receiving and viewing the mobile broadcast;
Means for receiving local content transmitted in a frequency band different from that of the mobile broadcast, and decoding and demodulating the content in the same process as the mobile broadcast;
A mobile terminal device comprising: A mobile terminal device capable of viewing mobile broadcasts,
The mobile broadcast receiving antenna;
A first down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal;
A local broadcast receiving antenna for receiving a local broadcast signal distributed in a frequency band different from the mobile broadcast band;
A second down converter that converts a received signal from the local content broadcast receiving antenna into a frequency near a mobile broadcast band;
Depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the first down converter is either the antenna for receiving the mobile broadcast or the output of the second down converter. Switching means for switching;
Demodulation / decoding means for demodulating and decoding the intermediate frequency signal output from the first down converter;
Output means for externally outputting image information or audio information obtained by the demodulation / decoding means;
A mobile terminal device comprising: A mobile terminal device capable of viewing mobile broadcasts,
The mobile broadcast receiving antenna;
A first down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal;
A local content broadcast receiving antenna for receiving a local broadcast signal distributed in a frequency band different from the mobile broadcast band;
A second down-converter that converts a signal received by the local content broadcast receiving antenna into the intermediate frequency signal;
Demodulation and decoding means for demodulating and decoding the intermediate frequency signal;
Depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the demodulation / decoding means is switched to the output of the first down converter or the second down converter. Switching means;
Output means for externally outputting image information or audio information obtained by the demodulation / decoding means;
A mobile terminal device comprising: A mobile terminal device capable of viewing mobile broadcasts,
The mobile broadcast receiving antenna;
A down converter that converts a frequency signal near the mobile broadcast band into a predetermined intermediate frequency signal;
A wireless LAN antenna capable of transmitting and receiving a wireless LAN signal in a frequency band different from the mobile broadcast band and receiving a local broadcast signal distributed in the frequency band;
A wireless LAN baseband processing unit, a transmission unit that upconverts a transmission baseband signal, and a reception unit that downconverts a reception signal from the wireless LAN antenna to a baseband;
Demodulation and decoding means for demodulating and decoding the intermediate frequency signal and the baseband signal;
Depending on whether the mobile broadcast or the local content broadcast is viewed, the input to the demodulation / decoding means is either an intermediate frequency signal output from the down converter or a baseband output of the reception unit Switching means to switch to,
Output means for externally outputting image information or audio information obtained by the demodulation / decoding means;
A mobile terminal device comprising: The scramble process is applied to the local broadcast reception stream.
A scramble key acquisition means for acquiring a scramble key through a predetermined procedure;
Descrambling means for descrambling the received stream using the obtained scramble key;
The mobile terminal device according to claim 10, further comprising: It further comprises notification means for detecting that it is in the service area of the local broadcast and notifying the user,
The mobile terminal device according to claim 10, wherein the mobile terminal device is a mobile terminal device. The local broadcast is composed of a plurality of channels obtained by segmenting a multicarrier modulation signal, of which at least one segment is provided with a control channel, and a service ID, a service name, a broadcast station ID, and a total channel related to the local broadcast Detailed information including at least one of the number, program ID, and presence / absence of encryption is broadcast on the control channel,
The notification means searches for a local broadcast control channel, and notifies the user that the local broadcast service area has been entered in response to detecting the control channel.
The mobile terminal device according to claim 15.