JP2002101025A - Voice information offering method, and voice information offering system used for the voice information offering method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method that utilizes a cable television transmission network for offering various voice information to a plurality of different regions at a low cost, and to provide a system that is used for the method. SOLUTION: The voice signal of an offering source is transmitted to an SP amplifier 10 by a head end 2 diverted from existing CATV facilities, an optical fiber 3, an optical node 4, a coaxial cable 5 for electrical mains, an electrical main amplifier 6, and a newly provided lead-in coaxial cable 7. Using the SP amplifier 10, the voice signal of a specific source is extracted for modulating to the voice signal of a prescribed frequency band, and radio waves containing a signal modulated by a leak cable 9a formed in a desired region are made to leak. The radio waves are received by a receiver 18, such as FM radio, thus acquiring local information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for providing predetermined audio information to a desired area via a cable television transmission network, and a system used for the method.

[0002]

2. Description of the Related Art Conventionally, FM leaked using a leaky cable in a tunnel or in some areas on a highway.
Road traffic information and the like by waves are broadcast. This is to transmit information on occurrence of a traffic accident and presence / absence of traffic congestion to a driver driving a vehicle by FM waves. In recent years, for example, FM broadcasting has been used to provide travelers and the like operating vehicles in a desired area with various types of information such as local special products and sightseeing spots using radio wave leaking means such as a leaking cable. There is the idea of revitalizing the local economy by using the advertising effect accompanying this. In such FM broadcasting, a dedicated cable is laid in a section from an FM broadcasting station that normally transmits audio information to an area that provides information, and the audio information is transmitted via the cable. However, laying such a dedicated cable has a practical problem because it requires cost and labor.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and uses a cable television transmission network to transmit various types of audio information to a plurality of different areas at low cost. And a system used for the method.

[0004]

According to one aspect of the present invention, there is provided a voice information providing method for providing voice information via a cable television transmission network. A signal transmitting step of transmitting to the signal modulating means via the cable television transmission network; and a signal modulating step of modulating the audio signal transmitted by the signal transmitting step to a frequency signal receivable by the audio receiving device by the signal modulating means. And a radio wave leaking step of leaking a radio wave including an audio signal modulated by the signal modulating means from a leaky cable to enable reception by the audio receiving device.

In this method, an audio signal is transmitted to a signal modulating means via a cable television transmission network, and is modulated by the signal modulating means into a frequency signal receivable by an audio receiving apparatus. , The voice information can be provided (transmitted) in a desired area where the leaked cable is provided, and can be received by the voice receiving device. For example, a leaky cable is laid along a road and a voice receiving device is mounted on a vehicle, so that appropriate voice information can be acquired for each region while the vehicle is running. In order to carry out this method, a signal transmission means such as a cable may be provided in a section from the nearest point on the existing cable television transmission network to the signal modulation means,
Since it is not necessary to newly lay the signal transmission section from the point at which the voice information is transmitted to the signal modulation means, it is possible to reduce the cost and labor required to lay the signal transmission cable.

According to a second aspect of the present invention, in the information providing method according to the first aspect, a plurality of types of sources are individually provided to the audio information, and the signal modulating means and the leaky cable include It is branched from a cable television transmission network and arranged in a desired area, and a signal of a desired source is extracted by the signal modulation means. In this method, a plurality of types of sources (for example, regional information, sightseeing / special product information, etc.) are individually provided via a cable television transmission network, and appropriate signals are provided by signal modulation means arranged in each region. By extracting the source, information corresponding to each region can be provided.

According to a third aspect of the present invention, in the information providing method according to the second aspect, each signal modulating means in the signal modulating step performs FM modulation in a fixed frequency band. In this method, each signal modulating means performs FM modulation in a certain frequency band on an audio signal transmitted through a cable transmission network, and sends out the modulated audio signal to a leaky cable. Radio waves in a certain frequency band are leaked. Therefore, the user who receives the provision of the voice information can receive the provision of the information using the general-purpose portable or on-vehicle FM voice receiving device (FM radio). There is no need to adjust the receiving frequency of the FM audio receiving device.

According to a fourth aspect of the present invention, in the information providing method according to the second aspect, the plurality of types of sources are stored in a storage unit in advance, and the source reproduced from the storage unit is , Transmitted to the signal modulation means via the cable television transmission network. In this method, the source stored in the storage means can be reproduced and transmitted to the signal modulation means, and the information of the same source can be provided as many times as necessary.
Note that audio information may be provided in real time.

According to a fifth aspect of the present invention, there is provided an audio information providing system for providing audio information via a cable television transmission network, wherein the signal transmission means transmits an audio signal of the information to be provided via the cable television transmission network. A signal modulating means for modulating a sound signal transmitted by the signal transmitting means to a frequency signal receivable by a sound receiving device, and a radio wave including the sound signal modulated by the signal modulating means leaked from a leak cable, Radio wave leakage means for enabling reception by the voice receiving device. In this configuration, the same operation as the first aspect can be obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A voice information providing system according to one embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of the voice information providing system, and FIG. 2 shows a main configuration of the system. The present system 1 transmits desired audio information (for example, regional information) by diverting a part of an existing cable television (hereinafter abbreviated as CATV) transmission network 20, and uses general-purpose F in a predetermined region.
The M radio receiver (speech receiving device) 18 is capable of receiving.

The existing CATV transmission network 20 is a broadcasting center facility, which is a cable head antenna end (hereinafter abbreviated as head end) 2 for transmitting audio signals and image signals as optical signals, and this head. An optical fiber 3 for transmitting an optical signal transmitted from the end 2 to the optical node 4, an optical node 4 for photoelectrically converting the optical signal transmitted by the optical fiber 3 into an electric signal, and an optical signal output from the optical node 4. The main signal coaxial cable 5 for transmitting the electric signal to the main line amplifier 6 and below, the main line amplifier 6 for amplifying the electric signal attenuated at the time of transmission by the main line coaxial cable 5, and the main signal coaxial cable 5 And a tap-off 8 (see FIG. 2) for splitting the electric signal and distributing it to the television owned by the CATV subscriber. In the CATV transmission network 20, transmission of electric signals from the trunk amplifier 6 and below is performed, as necessary, as shown in FIG. 2 by a branch coaxial cable 5a branched from the trunk amplifier 6 and a tap-off connected thereto. 8 may be used. The branch to the incoming coaxial cable 7 may be a branch from the nearest branch coaxial cable 5a using the incoming terminal 7a as shown in FIG. Note that reference numeral 17 in FIG. 1 denotes a dummy resistor provided at the end of the CATV transmission line.

The present system 1 uses a part of such a cable transmission network 20 to convert the audio signal amplified by the main line amplifier 6 into a signal processor amplifier (signal modulation means; hereinafter abbreviated as SP amplifier) 10. And a desired audio signal extracted from the audio signal transmitted by the coaxial cable 7 and modulated into an FM wave of a predetermined frequency band that can be received by the FM radio receiver 18. SP amplifier 10 for performing
And an output cable 9 partially provided with a leakage cable 9a (radio wave leakage means) for leaking radio waves in a frequency band including a modulated audio signal. The optical fiber 3, the optical node 4, the trunk coaxial cable 5, the trunk amplifier 6, and the pull-in coaxial cable 7 constitute a signal transmission unit. The radio wave leaked by the leak cable 9a is received by the FM radio receiver 18 owned by the user,
Desired audio information is provided.

The audio signal transmitted from the head end 2 is generated, for example, at a CATV center using a system as shown in FIG. In FIG. 3, the sound input from the recording microphone 11a is synthesized by the mixer 12 with various sound effects such as background music, and is recorded in the memory device 13 as a source by a digital method. Reference numeral 13a denotes an operation unit of the memory device 13, which instructs recording and transmission of a source. The contents of the source recorded in the memory device 13 can be confirmed while being reproduced by the monitor speaker 14, and if the mixer 12 and the recording microphone 11a are used, sound effects and voices can be further synthesized as necessary. it can. In the embodiment shown in FIG. 3, the memory device 13 records the sources (sources 1 to 10) for 10 stations (10 channels). The memory device 13 has a built-in automatic transmission function for the sources 1 to 10, and automatically transmits the recorded sources 1 to 10 to the modulators 15 (MO1 to MO10) by operating the operation unit 13a. The sources 1 to 10 transmitted from the memory device 13 are converted into analog signals by the modulator 15 and then synthesized by the mixer 16 as necessary, and transmitted to the head end 2 as audio signals.
The modulators MO1 to MO10 have sources 1 to 1 respectively.
In order to be able to transmit 0 to the mixer 16 at the same time, they are arranged corresponding to the respective sources 1 to 10. Further, the head end 2 of the present system can also transmit an audio signal for live broadcasting. In this case, the sound input from the live broadcast microphone 11b plus the sound effect of the mixer 12 is recorded in the memory device 13 as a source, and D / A converted via the modulator 15 as necessary. By synthesizing in the mixer 16, an audio signal is generated.
Here, the source of the live broadcast may be transmitted to the modulator 15 without being recorded in the memory device 13.

The audio signal generated as described above is converted into an optical signal by the head end 2 and transmitted to the optical node 4 closest to the area where the audio information is provided by the optical fiber 3 (FIG. 1). reference). Normally, a four-core type optical fiber 3 is used for CATV broadcasting. Of these, only two cores are used for signal transmission of CATV broadcasting, and the remaining two cores are used as closures as spare cores. It is closed by. For this reason, CA
A frequency for an unused channel not used for TV broadcasting can be used. More specifically, CA
One channel for TV broadcasting is normally configured with a 6 MHz band, and transmission of an audio signal of one station in the present system 1 requires a band of 500 kHz + α (adjacent band). The audio signals of 10 stations (sources 1 to 10 in FIG. 3) can be transmitted by one unused channel. Thus, CA
In an area where the optical fiber 3 for TV transmission has already been laid, there is no need to newly lay the optical fiber 3 and the installation of cables becomes easy. In an area where the optical fiber 3 is not laid, the laying may be performed by extending a spare core from the nearest optical fiber 3. In the CATV transmission network 20 used by the present system 1, the distance from the head end 2 to the optical node 4 tends to be longer with an increase in the viewing area. HFC with coaxial cable 5 for trunk line
By adopting the (Hybrid Fiber Coax) method, the transmission efficiency can be improved in the long distance section from the head end 2 to the optical node 4 by using the optical fiber 3 with low transmission loss, and the relay amplifier can be omitted.

The audio signal based on the optical signal transmitted from the head end 2 is transmitted to the optical node 4 using the spare core of the optical fiber 3. The optical node 4 receives the supply of power from a power supply 19 (see FIG. 2), photoelectrically converts the optical signal into an electric signal, and converts an audio signal based on the electric signal through the main coaxial cable 5 to the main line. Output to amplifier 6 and below. The coaxial cable used for the main line coaxial cable 5 generally has a large transmission loss and a large signal attenuation as compared with the optical fiber 3. Transmitting. For example, as shown in FIG.
Are provided at predetermined intervals (approximately 400 m) on the trunk route of the CATV transmission network 20.

In the present system 1, the head end 2 to the main line amplifier 6 in the CATV transmission network 20 are diverted, and the coaxial cable 7 for drop-in from the nearest main line amplifier 6 is connected to the SP amplifier 10. The audio signal output from the optical node 4 is transmitted to the SP amplifier 10 through the pull-in coaxial cable 7. Therefore, it is only necessary to newly arrange the cables after the lead-in coaxial cable 7 to arrange the cables, so that the cost can be reduced and the work process can be simplified. In this way, the audio signals of the sources 1 to 10 are transmitted from the head end 2 to the SP amplifier 10 via the CATV transmission network 20.
Is transmitted to

The SP amplifier 10 extracts an audio signal of a desired source from the audio signals of the sources 1 to 10 transmitted from the optical node 4. Each source is CAT as described above
An audio signal of a desired source can be extracted by extracting a signal of a specific frequency band since the signal is transmitted by a signal of a predetermined frequency band corresponding to an available channel for V broadcasting. Further, the SP amplifier 10 modulates the extracted audio signal into an FM wave in a predetermined frequency band that can be received by the FM radio receiver 18 and outputs the FM wave. Note that the SP amplifier 10
Is installed for each region (channel) where audio information is provided by hanging it on cables (suspension lines) such as a drawing coaxial cable laid outdoors.

The SP amplifier 10 has an output cable 9
As described above, the audio signal modulated to the FM wave of the predetermined frequency by the SP amplifier 10 is output to the output cable 9 as described above. The output cable 9 is formed by a leaky cable 9a in a predetermined fixed section as shown in FIG. The leaky cable 9a is a cable for leaking a radio wave including the modulated FM wave to the outside when transmitting the modulated FM wave. In the present system 1, such a leaky cable 9a is formed in a predetermined fixed section. This makes it possible to provide audio information by FM broadcasting in the area around the section. The laying of the coaxial cable 7 and the output cable 9 can be performed by hanging them on hangers provided for the cable system transmission line. In FIG. 4, reference numeral 21 denotes a power line, 22 denotes an NTT telephone line, and 23 denotes a power line.
Indicates a telephone pole.

In the present system 1, the CAT is
It is possible to provide audio information by FM broadcasting to a desired area using the V transmission network 20, but the area is not limited to one location, and audio information can be provided as shown in FIG. A coaxial cable 7 for branch is branched from a main line amplifier 6 nearest to a plurality of regions to be set, and an SP is provided downstream thereof.
By arranging the amplifiers 10 and below, it is possible to provide audio information of stations corresponding to a plurality of regions. That is, FIG.
The sources 1 to 10 to be recorded in the memory device 13 shown in (1) are recorded in advance in accordance with the contents corresponding to each region, and the audio signals of the sources 1 to 10 are transmitted from the head end 2 to the CATV transmission network 2 to each station.
0 to each of the SP amplifiers 10, and the source audio signal corresponding to each area is extracted by each of the SP amplifiers 10 and FM-modulated, and radio waves including the modulated signals are leaked by the leak cable 9a. By doing so, it is possible to provide audio information having different contents for each region.

As the type of audio information provided in this manner, various services and information provisions can be considered. As an example, the historical facts and legends transmitted at sightseeing spots such as famous places and historic spots in various places can be used. "Electronic Narrative Service (see FIG. 5)" broadcast to tourists who have visited the land. Tourists can use this as a sightseeing guide by receiving this broadcast on their mobile FM radio. As another example, there is a “FM voice sign service (see FIG. 6)” that broadcasts traffic information and the like along a road along a section where a leaky cable is laid. This is shown in FIG.
As shown in (a) to (d), special information on special products in various places,
It provides information on parking lots, traffic information such as traffic jams and construction, and the like, and the driver receives this broadcast through an FM radio mounted on the vehicle. In the present embodiment, these broadcasts are broadcast at the same frequency in any region (station) for each type of audio information. For example, when providing the voice information of the "electronic narrative service" in the tourist spot shown in FIG. 5, a band centered at 77.7 MHz and the voice of the "FM voice sign service" along the roadside shown in FIG. 88.8 MHz for providing information
, And these frequency bands are common to all regions. Therefore, the user can select the FM radio receiver 18 according to the type of information to be first known.
Is convenient because it is not necessary to readjust the reception frequency every time the user travels in each area.

The SP amplifier 10 is adjusted to change the frequency band of the audio signal to be extracted from the audio signals of the respective sources transmitted from the head end 2 via the CATV transmission network 20, whereby the SP amplifier is adjusted. The source extracted by 10 can be set arbitrarily. By adjusting the SP amplifier 10, the same source can be broadcast to a plurality of regions. For example, in the embodiment shown in FIG. 1, two SP amplifiers 10 adjusted so as to extract an audio signal in a frequency band corresponding to the source 1 of channel 1 (the uppermost SP amplifier 10 and the lowermost SP amplifier 10 in FIG. 1). Since the SP amplifiers 10) are arranged at two locations, the leakage cables 9a to F
M waves are leaked, and the same source 1 audio information can be provided in those surrounding areas.

Further, in FIG. 2, a lead-in terminal 7a is provided upstream of the tap-off 8, and the lead-in terminal 7a is provided.
Although the SP amplifier 10 is connected by the pull-in cable 7 extending from FIG. 1, the pull-in terminal 7a is provided downstream of the tap-off 8 as in the lowermost SP amplifier 10 in FIG. May be connected. At this time, as shown in FIG. 1, the lead-in coaxial cable 7 may extend from the downstream side of the plurality of tap-offs 8. That is, the SP amplifier 10 can be installed at any place on the CATV transmission network 20. However, in this case, in order to prevent interference of radio waves leaked from the leaky cable 9a, it is desirable that the leaky cables 9a corresponding to the respective channels are provided at a distance of about 500 m or more. It should be noted that, even if a weak radio wave that does not require permission is used as the broadcast radio wave transmitted by leakage, the reception range is narrow, but the broadcast radio wave can be sufficiently practical.

As described above, according to the present embodiment, CATV
By diverting a part of the transmission network 20, the audio signal is transmitted to the SP amplifier 10, a predetermined audio signal is extracted by the SP amplifier 10, and the frequency signal is modulated into a frequency signal receivable by the FM radio receiver 18 and leaked. Leakage of radio waves including audio signals from the cable 9a can provide audio information to a desired area. In the present embodiment, CA
Since a part of the TV transmission network 20 is diverted, the newly installed facilities include the output coaxial cable 7, the SP amplifier 10, and the output cable 9 including the leakage cable 9a. Is simplified. In addition, the CATV transmission network 2 used in this embodiment
0, HFC (Hybrid Fiber Coa
x) Since the method is adopted, high transmission efficiency can be obtained with a simple configuration.

In this embodiment, since information is provided using FM waves, the user can use the inexpensive and widely used portable or in-vehicle FM radio receiver 18 to perform various broadcasts. Service can be enjoyed.

Furthermore, in the present embodiment, in any region, for each type of audio information to be provided, FM waves of the same frequency band are broadcast, so that the user can select the type of information that he or she wants to know first. If the reception frequency of the FM radio receiver 18 is adjusted in this way, it is convenient since it is not necessary to adjust the reception frequency every time the user travels in each area. In addition, if the FM radio receiver 18 has a memory function of the reception frequency, storing the frequently used reception frequency in the FM radio receiver 18 in advance further enhances the convenience.

The present invention can be variously modified without being limited to the configuration of the above-described embodiment. For example, the radio wave leaking from the leaking cable 9a is not limited to the FM wave but may be the AM wave. Good. The information may be provided using character information in addition to general voice information.

Further, if a channel processor amplifier is applied instead of the SP amplifier 10 used in the present embodiment, it is possible to provide a plurality of types of audio information in one broadcasting area. Furthermore, the number of sources recorded in the memory device 13 is not limited to 10 stations, and can be increased according to the area where audio information is provided and the type of audio information to be provided by adding recording means in the memory device 13. .

Further, specific examples of the type of information to be provided are not limited to the above examples, and, for example, guidance broadcasting by voice to a visually impaired person or guidance broadcasting to an evacuation site in the event of a disaster It is also conceivable to provide information such as information on lifelines. In the latter case, in particular, not only can guided broadcasts having appropriate contents be performed for a plurality of disaster-stricken areas or evacuation sites, but also the victims do not need to change the reception frequency of the FM radio receiver 18 during evacuation. It can be used effectively.

[0029]

As described above, according to the first or fifth aspect of the present invention, the audio signal is transmitted to the signal modulation means via the existing cable television transmission network, and the audio reception apparatus receives the audio signal by the signal modulation means. By modulating to a possible frequency signal and leaking a radio wave including an audio signal from the leaky cable, audio information can be provided to a desired area where the leaky cable is arranged. In addition, an existing cable television transmission network can be used to transmit an audio signal, whereby a new signal transmission cable is laid over the entire section from a point at which audio information is transmitted to a signal modulation unit. This eliminates the necessity, so that the cost required for laying cables can be reduced, and an information providing service by audio broadcasting can be provided at low cost.

According to the second aspect of the present invention, an appropriate source is extracted from signal sources individually provided as audio information by signal modulating means arranged in a desired area, so that each area is extracted. Corresponding information can be provided, and detailed services can be handled.

Further, according to the third aspect of the present invention, since the FM wave in a certain frequency band is leaked from the leaky cable,
The user who receives the provision of the voice information can receive the provision of the voice information by the general-purpose FM voice receiving device.
Since information can be provided without adjusting the reception frequency of the voice receiving device for each destination area, user convenience is improved.

According to the fourth aspect of the present invention, since the source stored in the storage means can be reproduced and transmitted, the audio information of the same source can be provided as many times as necessary. it can.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an information providing system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a main configuration of the system.

FIG. 3 is a configuration diagram of CATV center equipment in the system.

FIG. 4 is a perspective view showing an example of laying a leakage cable in the system.

FIG. 5 is an explanatory diagram showing an example of a service using the system.

FIGS. 6A, 6B, 6C, and 6D are perspective views showing another example of a service using the system.

[Explanation of symbols]

 Reference Signs List 1 voice information providing system 3 optical fiber (signal transmission means) 4 optical node (signal transmission means) 5 main line coaxial cable (signal transmission means) 6 main line amplifier (signal transmission means) 7 pull-in coaxial cable (signal transmission means) 9a Leakage cable (radio wave leaking means) 10 SP amplifier (signal modulation means) 18 FM radio receiver (voice receiving device) 20 Cable television transmission network

Claims (5)

[Claims] An audio information providing method for providing audio information via a cable television transmission network, comprising: a signal transmission step of transmitting an audio signal of information to be provided to signal modulation means via the cable television transmission network; A signal modulating step of modulating the audio signal transmitted by the signal transmitting step into a frequency signal receivable by an audio receiving device by the signal modulating means; and a radio cable including the audio signal modulated by the signal modulating means. And a radio wave leaking step of allowing the sound to be received by the sound receiving device. 2. A plurality of types of sources are individually provided for the audio information, and the signal modulation means and the leaky cable are branched from the cable television transmission network and arranged in a desired area. 2. The audio information providing method according to claim 1, wherein a signal of a desired source is extracted by the signal modulation unit. 3. The audio information providing method according to claim 2, wherein, in the signal modulation step, each signal modulation unit performs FM modulation in a fixed frequency band. 4. The plurality of types of sources are stored in a storage unit in advance, and the source reproduced from the storage unit is transmitted to the signal modulation unit via the cable television transmission network. 3. The audio information providing method according to claim 2, wherein: 5. An audio information providing system for providing audio information via a cable television transmission network, comprising: signal transmission means for transmitting an audio signal of information to be provided via the cable television transmission network; A signal modulating means for modulating the audio signal transmitted by the audio receiving apparatus into a frequency signal receivable by the audio receiving apparatus; and a radio wave including the audio signal modulated by the signal modulating means is leaked from a leak cable, and the audio receiving apparatus An audio information providing system, comprising: a radio wave leaking means for enabling reception of an audio signal.