JP2010093542A - Information distribution system, transmitter, and repeater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily ensure an information distribution service with an area from 10 meters to dozens of meters or below as a target. <P>SOLUTION: This transmitter 12 transmits content transferred from a content management device 11. A radio wave used for content transmission is a radio wave of a frequency at 322 MHz or below, and an output level is adjusted such that an electric field strength at a position separated by three meters is always at 500μV/m or below. Repeaters 21-1 and 21-2 which receive the radio wave from the transmitter 12 retransmit the content. A radio wave used for content retransmission is a radio wave of a frequency that exceeds 322 MHz, and an output level is adjusted such that the electric field strength at the position separated by three meters is always at 35μV/m or below. The invention is applicable to a system for achieving a service that targets on a user of a portable device corresponding to one-segment broadcasting. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an information distribution system, a transmission device, and a relay device, and in particular, an information distribution system that can easily realize an information distribution service for an area of several meters to several tens of meters or less, The present invention relates to a transmission device and a relay device.

  In recent years, mobile devices compatible with One Seg (trademark) broadcasting have become widespread. One-Seg broadcasting divides the UHF band of 470-710MHz into 40 channels of 13-52Ch, divides the frequency bandwidth of one channel of 6MHz into 13 segments, of which one segment is the band This is a broadcast for mobile devices that is used.

  With the widespread use of mobile devices compatible with 1Seg broadcasting, services for users who have such mobile devices compatible with 1Seg broadcasting have been proposed or realized.

  For example, Patent Document 1 discloses a service that divides a wide area into areas such as several kilometers and broadcasts contents specialized for each area. Patent Document 2 discloses a service for distributing odds information by forming a narrower area of several hundred meters in a public racetrack or the like.

Patent Document 3 discloses a technique for retransmitting a terrestrial digital broadcast signal received by an antenna installed outdoors using a radio wave having a frequency of 322 MHz or less with a device in the home.
JP 2007-295341 A JP 2008-97389 A Japanese Patent Laid-Open No. 2005-12583

  Broadcasting services for specific areas such as those disclosed in Patent Documents 1 and 2 are a very useful new form of service. Therefore, it is necessary to assign a new frequency to avoid interference with radio waves of existing radio stations, and it takes time and money to commercialize.

  On the other hand, the re-transmission of digital broadcasting disclosed in Patent Document 3 has a technical problem that it is affected by signal fluctuations in order to receive and re-transmit a spatial wave. In addition, legally, it is necessary to obtain the consent of the right holder for re-transmission because it is “re-transmission”. Furthermore, whether or not such re-transmission may be performed in the public place. There is a problem.

  The present invention has been made in view of such a situation, and makes it possible to easily realize an information distribution service for an area of several meters to several tens of meters or less.

  The information distribution system according to the present invention is an information distribution system comprising a transmission device and a relay device, wherein the transmission device is a radio wave having a frequency of 322 MHz or less and is stronger than the radio wave output by the relay device. Is provided. In addition, the relay device is provided within a reach of a radio wave output from the transmission device, and receives the content transmitted from the transmission device, and the content received by the reception device as one segment. Transmission means for transmitting using a radio wave having the same frequency as a radio wave used for broadcasting and having an electric field strength of 35 μV / m or less at a position 3 m away.

  The transmission device of the present invention includes transmission means for transmitting content using a radio wave having a frequency of 322 MHz or less and stronger than the radio wave output from the relay device.

  The transmission means can transmit a radio wave having an electric field strength of 500 μV / m or less at a position 3 m away as a radio wave stronger than the radio wave output from the relay device.

  The transmission means can transmit different contents using a plurality of radio waves having different frequencies of 322 MHz or less.

  Provided within the reach of radio waves output by other transmitters, receive content transmitted from the other transmitters, and receive the received content with radio waves having the same frequency as radio waves used for one-segment broadcasting It is possible to further provide receiving means for receiving radio waves from other relay devices that transmit using radio waves having an electric field strength of 35 μV / m or less at a position 3 m away. In this case, the transmission unit can further transmit the content acquired by receiving the radio wave from the other relay device by the reception unit.

  The relay device according to the present invention includes a receiving unit that receives content transmitted from a transmitting device, and the content received by the receiving unit is a radio wave having the same frequency as that of a radio wave used for one-segment broadcasting and is 3 m away. Transmitting means for transmitting using a radio wave having an electric field strength of 35 μV / m or less at the position.

  The transmission means can transmit different contents using a plurality of radio waves having different frequencies.

  In the information distribution system of the present invention, the content is transmitted by the transmission device using radio waves having a frequency of 322 MHz or less and stronger than the radio waves output from the relay device. Further, the content transmitted from the transmission device is received by the relay device, and the received content is a radio wave having the same frequency as the radio wave used for one-segment broadcasting, and the electric field strength at a position 3 m away is 35 μV. Sent using radio waves below / m.

  In the transmission apparatus of the present invention, content is transmitted using radio waves having a frequency of 322 MHz or less and stronger than the radio waves output from the relay apparatus.

  In the relay device of the present invention, the content transmitted from the transmitting device is received, and the received content is a radio wave having the same frequency as the radio wave used for one-segment broadcasting, and the electric field strength at a position 3 m away is 35 μV. Sent using radio waves below / m.

  According to the present invention, it is possible to easily realize an information distribution service for an area of several meters to several tens of meters or less.

[About the frequency and intensity of radio waves]
FIG. 1 is a diagram for explaining the reach of radio waves.

  The 1Seg transmitter 1 is a device that transmits radio waves having the same frequency as radio waves used in 1Seg broadcasting. The radio waves output by the one-segment transmitter 1 are not so strong as to cover a range of several hundred meters or several kilometers, but are weak enough that a license is not required for installing a radio station. Hereinafter, radio waves having a strength that does not require a license for installation of radio stations are simply referred to as weak radio waves.

  FIG. 2 is a diagram showing the relationship between the frequency and intensity of radio waves.

  The horizontal axis in FIG. 2 represents frequency, and the vertical axis represents intensity. As shown in FIG. 2, the strength of radio waves that do not require a license is defined according to the frequency as the electric field strength at a position 3 m away from the radio station that outputs the radio waves.

  For example, in a frequency band of 0 kHz to 322 MHz or less, a license is not required if the electric field strength at a position 3 m away from the radio station is always 500 μV / m or less.

  In the frequency band exceeding 322 MHz and about 10 GHz or less, a license is not required if the intensity of the radio wave at a position 3 m away from the wireless station is always 35 μV / m or less. Since the frequency of radio waves used for one-segment broadcasting based on the ISDB-T terrestrial digital broadcasting standard is 470 to 710 MHz in the UHF band, when using radio waves of the same frequency, the intensity at a position 3 m away from the radio station is If it is 35μV / m or less, no license is required.

  According to the specified value of the radio field intensity and the reception sensitivity of a general one-seg broadcasting-compatible portable device, the area where radio waves can be received from a radio station is an area with a radius of about 2 to 3 m as a theoretical calculation value. An area where stable reception is possible is an area with a radius of about 1 m.

  If the one-seg transmitter 1 is used to provide a service, only a user of a one-seg broadcasting-compatible portable device within an area with a radius of about 1 m is targeted, so the service area needs to be expanded.

  FIG. 3 is a diagram illustrating an example in which a plurality of wireless stations having the same functions as those of the one-segment transmitter 1 are arranged.

  As shown in FIG. 3, it is conceivable to expand the service area by arranging a plurality of wireless stations, but in reality, if the synchronization of the transmission timing of each wireless station is not ensured, the radio waves output by the wireless stations The range that can be normally received is narrowed.

  That is, even if a plurality of wireless stations are simply arranged, the effect of expanding the service area is limited, and conversely, it is difficult to receive radio waves near the boundary of the area.

In the example of FIG. 3, areas A _{1 to} A _{3 that} are areas with a radius of about 1 m are formed by the one-segment transmitters 1-1 to 1-3, respectively. In the vicinity of the boundary between the areas A ₁ and A _{2 and} the boundary between the area A ₂ and the area A ₃ indicated by the alternate long and short dash line, radio wave interference occurs, so that information from the radio station cannot be received and demodulated normally.

  In the information distribution system to which the present invention is applied, it is possible to easily realize broadcasting and information services for an area of several meters to several tens of meters or less using such a radio station. Yes.

[Configuration of information distribution system]
FIG. 4 is a diagram illustrating a configuration example of an information distribution system according to an embodiment of the present invention.

  As shown in FIG. 4, the information distribution system includes a content management device 11, a transmission device 12, and relay devices 21-1 and 21-2. Although two devices, relay devices 21-1 and 21-2, are shown as relay devices, the number of relay devices is arbitrary.

  The content management device 11 stores, for example, moving image content in a predetermined format, and transfers the stored content to the transmission device 12. The content transfer from the content management apparatus 11 to the transmission apparatus 12 may be performed via a wire such as a coaxial cable, or may be performed via radio.

  Further, the content acquired via a network such as the Internet may be transferred from the content management apparatus 11 instead of transferring the stored content.

  The transmission device 12 has a wired or wireless high-frequency signal input unit, and receives the content transferred from the content management device 11 at the input unit. When the content is transferred via radio, radio waves having a UHF band frequency exceeding 322 MHz may be used, or radio waves having a frequency of 322 MHz or less may be used.

The transmission device 12 is a weak radio station having a function of transmitting a weak radio wave having a frequency f _V1 of 322 MHz or less.

  The transmission device 12 has a function of adjusting the output level of the radio wave so that the electric field strength at a position 3 meters away from the position of the transmission device 12 is always 500 μV / m or less. Since the radio wave output from the transmitter 12 is a radio wave of 322 MHz or less, as described with reference to FIG. 2, if the electric field strength at a position 3 meters away is 500 μV / m or less, a license is required for installation of the device. Is no longer necessary.

An area A ₁₁ indicated by a broken line in FIG. 4 is an arrival range of the weak radio wave transmitted by the transmission device 12. Area A ₁₁ will radius of about about 5 to 10 m area.

The transmission device 12 transmits the content transferred from the content management device 11 using such a weak radio wave having the frequency f _V1 . The transmission device 12 appropriately changes the frequency of the weak radio wave by controlling an internal oscillator and a synthesizer, and transmits content.

The relay devices 21-1 and 21-2 are installed at different positions in the area A ₁₁ where the weak radio waves from the transmission device 12 reach.

The relay devices 21-1 and 21-2 have a function of receiving a weak radio wave with a frequency f _V1 transmitted by the transmission device 12, a function of transmitting a weak radio wave with a frequency f _{U1 in} the UHF band exceeding 322 MHz, and a distance of 3 meters. And a function of adjusting the output level of the radio wave so that the electric field strength at a certain position is always 35 μV / m or less.

The frequency f _U1 that is the frequency of the weak radio wave output from the relay devices 21-1 and 21-2 is a frequency in a band of 470 to 710 MHz that is used in one-segment broadcasting.

  Since the radio waves output from the relay devices 21-1 and 21-2 are radio waves in the band of 470 to 710 MHz exceeding 322 MHz, the electric field strength at a position 3 meters away as described with reference to FIG. 2 is 35 μV / If it is less than or equal to m, no license is required to install the device.

An area A ₁₂ indicated by a solid line in FIG. 4 is a reach range of a weak radio wave transmitted by the relay device 21-1, that is, a service area covered by the relay device 21-1. Area A ₁₃ is a reach of a weak radio wave transmitted by the relay device 21-2, that is, a service area covered by the relay device 21-2. The range in which the weak radio waves transmitted by the relay devices 21-1 and 21-2 can be stably received is a range of about 1 meter in radius as described above.

The relay apparatuses 21-1 and 21-2 transmit the content acquired by receiving the weak radio wave from the transmission apparatus 12 using such a weak radio wave with the frequency f _U1 . In the relay apparatuses 21-1 and 21-2, the content transmitted using the weak radio wave of 322 MHz or less is retransmitted using the weak radio wave exceeding 322 MHz. The relay devices 21-1 and 21-2 appropriately change the frequency of the radio wave by controlling the internal oscillator and the synthesizer, and transmit the content.

  As described above, the weak radio waves output from the relay devices 21-1 and 21-2 are radio waves having a frequency band of 470 to 710 MHz used in one-segment broadcasting.

Therefore, by placing a portable device compatible with the one-segment broadcasting in the area A ₁₂ , the user of the portable device can display and view the content retransmitted by the relay device 21-1 on the display of the portable device. . Similarly, by placing a mobile device compatible with one-segment broadcasting in the area A ₁₃ , the user of the mobile device can display the content retransmitted by the relay device 21-2 on the display of the mobile device and view it. it can.

  As described above, in the information distribution system of FIG. 4, the content is not directly provided from the transmission device 12, but is relayed by the relay devices 21-1 and 21-2 that have received weak radio waves from the transmission device 12. Content is provided.

  Although there are few portable devices equipped with a function of receiving radio waves of 322 MHz or less, portable devices equipped with a function of receiving radio waves in the band of 470 to 710 MHz are generally spread as portable devices compatible with one-segment broadcasting. It becomes possible to provide services for users.

  Further, only one content management device 11 needs to be prepared as a content providing source, and a device serving as a content providing source, such as one for the relay device 21-1 and one for the relay device 21-2, is used. There is no need to prepare each.

  Since the radio waves used by the transmitter 12 and the radio waves used by the relay devices 21-1, 21-2 are weak radio waves that do not require a license, the service providing side can easily realize services according to various needs. can do.

The information distribution system shown in FIG. 4 is constructed in a store such as a restaurant. As an image, at least the transmission device 12 is installed near the center of the store, and a relay device is installed on each table in the store. Since only the relay device is installed, a service area in which content can be viewed can be easily constructed in the area A ₁₁ that is the reach of the weak radio wave transmitted by the transmission device 12 as necessary. It becomes possible.

  In addition to restaurants, service areas that cover a narrow area, such as every exhibition corner for products in a store, every seat in a movie theater or train, and every exhibition corner for exhibits in museums or museums, are required. It is possible to build. In addition, by providing a large number of such viewing areas, it is possible to construct a service area on the entire floor of such a store or movie theater.

  In the above, the content management device 11 and the transmission device 12 are prepared as separate devices, but the content management device 11 and the transmission device 12 may be realized by one device.

  In the above, the content to be distributed is assumed to be video content. However, if the content can be transmitted from a relay device using the same frequency as that used in one-segment broadcasting, Other contents such as a picture, music, a game, and text may be used.

[Configuration of each device]
FIG. 5 is a block diagram illustrating a configuration example of the transmission device 12 of FIG.

  As illustrated in FIG. 5, the transmission device 12 includes a high-frequency signal input unit 31, a filter unit 32, a mixer unit 33, a local oscillation unit 34, a filter unit 35, an output level adjustment unit 36, and an antenna 37.

  The high-frequency signal input unit 31 receives a high-frequency signal (content) input from the content management device 11 via wire or wirelessly, and amplifies the signal level necessary for signal processing inside the transmission device, and a filter unit 32.

The filter unit 32 passes the signal in the band of the frequency f _U out of the high frequency signal supplied from the high frequency signal input unit 31 and outputs the signal to the mixer unit 33. When content is input wirelessly from the content management device 11 to the transmission device 12, filtering by the filter unit 32 is necessary.

Based on the signal of the frequency f _U supplied from the filter unit 32 and the signal of the frequency f _L supplied from the local oscillating unit 34, the mixer unit 33 differs from the signal f _U + f _L representing the sum of these signals. It generates a signal f _U -f _L representing a, and outputs a signal f _U + f _L and the signal f _U -f _L to the filter unit 35.

The local oscillating unit 34 selects a frequency to be used as an oscillating frequency from a plurality of predetermined frequencies, and outputs a signal having a frequency f _L to the mixer unit 33. The local oscillation unit 34 is configured by a synthesizer or an oscillator.

Filter unit 35, among the supplied signals f _U + f _L and the signal f _U -f _L from the mixer unit 33, to cut off the signal f _U + f _L, passing signals f _U -f _L.

The output level adjustment unit 36 adjusts the output level so that the electric field strength at a position 3 meters away is always 500 μV / m or less, and transmits the signal f _U −f _L supplied from the filter unit 35, which is 322 MHz or less. A weak radio wave having a frequency of 1 is output from the antenna 37. The frequency f _{V1 in} FIG. 4 is represented by f _U −f _L.

  FIG. 6 is a block diagram illustrating a configuration example of the relay device 21-1 in FIG. The relay device 21-2 has the same configuration.

  As illustrated in FIG. 6, the relay device 21-1 includes an antenna 51, a high-frequency signal input unit 52, a filter unit 53, a mixer unit 54, a local oscillation unit 55, a filter unit 56, an output level adjustment unit 57, and an antenna 58. Composed.

  The high-frequency signal input unit 52 receives a high-frequency signal (content) supplied from the antenna 51 when a weak radio wave from the transmission device 12 is received, and has a signal level necessary for signal processing inside the relay device. Amplified and output to the filter unit 53.

The filter unit 53 passes the signal having the frequency f _V1 among the high-frequency signals supplied from the high-frequency signal input unit 52 and outputs the signal to the mixer unit 54.

Based on the signal of the frequency f _V1 supplied from the filter unit 53 and the signal of the frequency f _L supplied from the local oscillating unit 55, the mixer unit 54 differs from the signal f _V1 + f _L representing the sum of these signals. It generates a signal f _V1 -f _L representing a, and outputs a signal f _V1 + f _L and the signal f _V1 -f _L to the filter unit 56.

The local oscillating unit 55 selects a frequency to be used as an oscillation frequency from a plurality of predetermined frequencies, and outputs a signal having a frequency f _L to the mixer unit 54. A signal having the same frequency as the frequency generated by the local oscillation unit 34 of the transmission device 12 is generated by the local oscillation unit 55. The local oscillating unit 55 includes a synthesizer and an oscillator.

Filter unit 56, among the supplied signals f _V1 + f _L and the signal f _V1 -f _L from the mixer unit 54, to cut off the signal f _V1 -f _L, passing signals f _V1 + f _L.

The output level adjustment unit 57 adjusts the output level so that the electric field strength at a position 3 meters away is always 35 μV / m or less, and transmits the signal f _V1 + f _L supplied from the filter unit 56, 470 to 710 MHz. A weak radio wave with a frequency in the band is output from the antenna 58. The frequency f _{U1 in} FIG. 4 is represented by f _V1 + f _L.

[Modification 1]
FIG. 7 is a diagram illustrating another configuration example of the information distribution system.

  Of the configurations shown in FIG. 7, the same configurations as those shown in FIG. The overlapping description will be omitted as appropriate. The same applies to FIGS. 8 and 9 described later.

  In the example of FIG. 7, content management apparatuses 11-1 and 11-2 are provided as content providing apparatuses. The content management apparatuses 11-1 and 11-2 output content signals having different contents to the mixer 61.

  The mixer 61 mixes the signal supplied from the content management device 11-1 and the signal supplied from the content management device 11-2, and outputs the obtained signal to the transmission device 12.

  The content management device 11-1 and the mixer 61, the content management device 11-2 and the mixer 61, and the mixer 61 and the transmission device 12 are connected, for example, via a wired cable.

  The transmission device 12 receives the signal transmitted from the mixer 61, and acquires the content output from the content management device 11-1 and the content output from the content management device 11-2.

The transmission apparatus 12, using the weak radio wave of a frequency below f _V1 322 MHz, and transmits the content output by the content management apparatus 11-1 is a frequency different from the frequency f _V1, 322 MHz frequencies below f _V2 The content output from the content management apparatus 11-2 is transmitted using the weak radio wave. The transmission device 12 has a function of receiving a plurality of content signals and transmitting them using radio waves of different frequencies.

The relay devices 21-1 and 21-2 receive weak radio waves having the frequencies f _V1 and f _V2 transmitted by the transmission device 12.

In addition, the relay devices 21-1 and 21-2 transmit the content output from the content management device 11-1 using a weak radio wave having a frequency f _U1 within a band of 470 to 710 MHz, and within the band of 470 to 710 MHz. The content output from the content management apparatus 11-2 is transmitted using a weak radio wave having a frequency f _U2 which is a frequency different from the frequency f _U1 . The relay devices 21-1 and 21-2 have a function of receiving a plurality of radio waves having different frequencies, converting the radio waves to radio waves having different frequencies, and retransmitting them.

The user, for example, place the portable device compatible with one-segment broadcasting in the area A ₁₂ is a service area of the relay apparatus 21-1, one of the channels of the weak radio wave of weak radio frequency f _U2 frequency f _U1 By selecting, the content to be viewed can be switched.

[Modification 2]
FIG. 8 is a diagram illustrating another configuration example of the information distribution system.

  In the example of FIG. 8, a content management apparatus 11-1 is provided as a content providing apparatus for the transmitting apparatus 12-1, and a content management apparatus 11-2 is provided as a content providing apparatus for the transmitting apparatus 12-2. Is provided. The content management device 11-1 and the content management device 11-2 each output content having different contents.

  The content management device 11-1 and the transmission device 12-1, and the content management device 11-2 and the transmission device 12-2 move together, for example, at a constant speed along the locus indicated by the broken-line arrow in FIG. To do. For example, a belt is disposed along a trajectory indicated by a broken-line arrow in FIG. 8, and a device placed on the belt is moved by rotating the belt using a carriage.

The transmission device 12-1 transmits content output from the content management device 11-1 using a weak radio wave having a frequency f _V1 of 322 MHz or less.

Similarly, the transmission device 12-2 transmits the content output by the content management device 11-2 using a weak radio wave having a frequency f _V1 of 322 MHz or less.

The relay device 21-1 existing at the timing shown in FIG. 8 within the area A ₂₁ that is the reach of the radio wave from the transmission device 12-1 receives the weak radio wave of the frequency f _V1 transmitted by the transmission device 12-1. , Get content. Further, the relay device 21-1 retransmits the content using the weak radio wave having the frequency f _U1 within the band of 470 to 710 MHz.

Also, the relay device 21-2 existing at the timing shown in FIG. 8 in the area A ₂₂ that is the reach of the radio wave from the transmission device 12-2 transmits the weak radio wave having the frequency f _V1 transmitted by the transmission device 12-2. Receive and get content. In addition, the relay device 21-2 retransmits the content using the weak radio wave having the frequency f _U1 in the band of 470 to 710 MHz.

  The positions of the relay devices 21-1 and 21-2 are fixed. Further, the relay devices 21-1 and 21-2 are installed at positions separated from each other so as not to simultaneously receive radio waves from a plurality of transmission devices.

Considering the relay device as a reference, the content transmitted by the weak radio wave of the frequency f _V1 is switched by the movement of the transmission device, and accordingly, the relay devices 21-1 and 21-2 use the weak radio wave of the frequency f _U1. The content to be transmitted is also switched.

For example, the user automatically places a plurality of contents by placing a portable device that supports one-seg broadcasting in the area A ₃₁ that is a service area of the relay device 21-1, and continuously receiving weak radio waves of the same frequency f _U1. You can switch and watch.

[Modification 3]
FIG. 9 is a diagram illustrating another configuration example of the information distribution system.

  In the example of FIG. 9, by using a plurality of sets of transmission devices and relay devices, a service area can be constructed at a predetermined interval in a long distance section such as in a train or a platform of a station. ing.

The transmission device 12-1 transmits the content output from the content management device 11 using a weak radio wave having a frequency f _V1 of 322 MHz or less.

The relay device 21-1 installed in the area A ₄₁ that is the reach of the radio wave from the transmission device 12-1 receives the weak radio wave of the frequency f _V1 transmitted by the transmission device 12-1 and acquires the content. To do. Further, the relay device 21-1 retransmits the content using the weak radio wave having the frequency f _U1 within the band of 470 to 710 MHz.

The user can view the content by bringing a mobile device compatible with one-segment broadcasting into the area A ₅₁ which is the service area of the relay device 21-1.

The transmission device 12-2 is installed in an area A ₅₁ that is a service area of the relay device 21-1. The transmission device 12-2 receives the weak radio wave having the frequency f _U1 transmitted by the relay device 21-1, and acquires the content.

Further, the transmission device 12-2 retransmits the content using a weak radio wave having a frequency f _V2 of 322 MHz or less, which is different from the frequency f _V1 output from the transmission device 12-1.

That is, in the example of FIG. 9, the transmitting device 12-2 not only outputs a weak radio wave having a frequency f _V2 of 322 MHz or less, but also has a function of receiving a weak radio wave having a frequency f _U1 within a band of 470 to 710 MHz. Have.

The relay device 21-2 installed in the area A ₄₂ that is the reach of the radio wave from the transmission device 12-2 receives the weak radio wave of the frequency f _V2 transmitted by the transmission device 12-2 and acquires the content. To do. In addition, the relay device 21-2 retransmits the content using the weak radio wave having the frequency f _U1 in the band of 470 to 710 MHz.

The user can view the content by bringing the mobile device compatible with one-segment broadcasting into the area A ₅₂ which is the service area of the relay device 21-2.

  Viewing a content output from the content management device 11 by installing a set of devices having functions similar to those of the transmission device 12-2 and the relay device 21-2 in that order after the relay device 21-2 Possible areas can be constructed at predetermined intervals in a section having a long distance.

  The embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

It is a figure explaining the reach | attainment range of an electromagnetic wave. It is a figure which shows the relationship between the frequency and intensity | strength of an electromagnetic wave. It is a figure which shows the example which has arrange | positioned two or more radio stations. It is a figure which shows the structural example of the information delivery system which concerns on one Embodiment of this invention. FIG. 5 is a block diagram illustrating a configuration example of the transmission device in FIG. 4. FIG. 5 is a block diagram illustrating a configuration example of the relay device in FIG. 4. It is a figure which shows the other structural example of an information delivery system. It is a figure which shows the other structural example of an information delivery system. It is a figure which shows the other structural example of an information delivery system.

Explanation of symbols

  11 content management device, 12 transmission device, 21-1, 21-2 relay device

Claims (7)

In an information distribution system consisting of a transmission device and a relay device,
The transmitter is
A transmission means for transmitting content using a radio wave having a frequency of 322 MHz or less and stronger than the radio wave output by the relay device;
The relay device is
Provided within the reach of the radio wave output by the transmitter,
Receiving means for receiving the content transmitted from the transmitting device;
Transmitting means for transmitting the content received by the receiving means using radio waves having the same frequency as radio waves used for one-segment broadcasting and having an electric field strength of 35 μV / m or less at a position 3 m away; Information distribution system provided. The transmission device is provided within the reach of the radio wave output from the transmission device, receives the content transmitted from the transmission device, and the received content is a radio wave having the same frequency as the radio wave used for one-segment broadcasting. In the transmission device of the information distribution system comprising a relay device that transmits using a radio wave whose electric field intensity at a position 3 m away is 35 μV / m or less,
A transmission apparatus comprising: a transmission unit configured to transmit the content using a radio wave having a frequency of 322 MHz or less and stronger than a radio wave output from the relay apparatus. The transmission device according to claim 2, wherein the transmission unit transmits a radio wave having an electric field strength of 500 μV / m or less at a position 3 m away as a radio wave stronger than the radio wave output from the relay device. The transmission device according to claim 2, wherein the transmission unit transmits different contents using a plurality of radio waves having different frequencies of 322 MHz or less. Provided within the reach of radio waves output by other transmitters, receive content transmitted from the other transmitters, and receive the received content with radio waves having the same frequency as radio waves used for one-segment broadcasting A receiving means for receiving a radio wave from another relay device that transmits using a radio wave having an electric field strength of 35 μV / m or less at a position 3 m away;
The transmission device according to claim 2, wherein the transmission unit further transmits content acquired by receiving radio waves from the other relay device by the reception unit. In the relay device provided within the reach of the radio wave output by the transmitter that transmits the content using radio waves having a frequency of 322 MHz or less and stronger than the radio wave output by the relay device itself,
Receiving means for receiving the content transmitted from the transmitting device;
Transmitting means for transmitting the content received by the receiving means using radio waves having the same frequency as radio waves used for one-segment broadcasting and having an electric field strength of 35 μV / m or less at a position 3 m away; A relay device provided. The relay device according to claim 6, wherein the transmission unit transmits different contents using a plurality of radio waves having different frequencies.

Images