JPH10308695A - Satellite broadcasting system and its gap filler device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit not only a fixed station but also a moving station to securely receive a signal without providing a large equipment in a dead zone where radio signals from a satellite cannot directly be received. SOLUTION: A gap filler device GFa is installed on the roof of a building. The gap filler device GFa receives and amplifies a broadcasting signal transmitted from a geostationary satellite SAT1 and relays/transmits the received broadcasting signal to the dead area at a frequency equal to that of the broadcasting signal from the geostationary satellite SAT1 by using a directional antenna.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for transmitting information to a terrestrial service area using a broadcasting satellite or a communication satellite, and more particularly, to reliably receive information even in a shadow area such as a mountain or a building. The present invention relates to a satellite broadcasting system having a gap filler function for enabling the system and a gap filler device thereof.

[0002]

2. Description of the Related Art In recent years, various communication systems have been developed in accordance with the increase in communication needs and the development of communication technologies. Among them, there are satellite broadcasting systems using broadcasting satellites and communication satellites. An advantage of the satellite broadcasting system is that information broadcasting services can be provided to a wide range of service areas without installing a large-scale infrastructure on the ground.

Incidentally, one of the problems of this type of system is a countermeasure against a shadow of a building where a direct wave from a satellite cannot be received. On the other hand, conventionally, a large-diameter common antenna is installed on the roof of a high-rise building or a steel tower, for example, and a radio signal from a satellite is received and amplified by the common antenna, and the received radio signal is transmitted via a coaxial cable or an optical cable. To the receiving device of each user behind the building.
In this way, even a user behind a building or the like that cannot receive a radio signal from a satellite can receive transmission information from the satellite without omission.

[0004]

However, such a joint receiving facility requires large-scale construction and cost since cables must be laid for each target user without exception. Recently, it has been proposed to transmit information not only to fixed stations but also to mobile stations using a satellite broadcasting system. In this case, if the user behind the building is a fixed station, the information from the satellite can be received by the above-described joint receiving facility. But,
Since a coaxial cable or an optical cable cannot be laid for a mobile station behind a building, information from a satellite cannot be received.

The present invention has been made in view of the above circumstances, and has as its object to provide a fixed station without providing large-scale facilities in an area such as a building behind which a radio signal from a satellite cannot be directly received. It is another object of the present invention to provide a satellite broadcasting system and a gap filler device capable of reliably receiving a signal from a mobile station and thereby realizing an inexpensive and effective gap filler.

[0006]

In order to achieve the above object, a satellite broadcasting system according to the present invention receives a broadcast signal relayed by a satellite, and broadcasts the received broadcast signal in the service area from the satellite. A gap filler device for wirelessly transmitting signals to an area where signals cannot be received is provided.

[0007] In this way, the radio signal from the satellite is received by the gap filler device and then retransmitted to the shadow of the building by radio. For this reason, since it is not necessary to lay a coaxial cable or an optical cable for each user behind the building, it can be realized relatively easily and inexpensively. Also,
In the shadow of a building, not only a fixed station but also a mobile station can receive information from a satellite. Further, since the radio signal is transmitted from the gap filler device at the same frequency, the user can receive the radio signal from the gap filler device only by having a receiving device that receives a direct wave from a satellite.

[0008] The gap filler device is characterized in that a directional antenna is used to transmit a received broadcast signal by radio to an area in the service area where a broadcast signal from a satellite cannot be received, with directivity. I have. By doing so, it is possible to reduce a problem that a user in an area that can directly receive a radio signal from a satellite receives interference due to a radio signal retransmitted from the gap filler device.

When the satellite is a geosynchronous satellite located in a geosynchronous orbit above the equator, it is preferable to transmit the received broadcast signal from the gap filler device with directivity in the east-west direction. Generally, when a radio signal is transmitted from a geostationary satellite arranged in a geosynchronous orbit above the equator, a radio wave is shadowed on the north side of an obstacle such as a building on the ground. For this reason, in an area where a number of buildings are lined up, such as an office district or a downtown district, if the gap filler device directs east and west, and retransmits a radio signal, the north side of the building district Shadows can be effectively covered.

[0010] At least one of the terrestrial broadcasting station and the satellite transmits a broadcast signal by performing spread spectrum modulation using a predetermined spreading code, and a gap filler device transmits the spread spectrum modulated broadcast signal transmitted from the satellite. , And wirelessly transmitting the received broadcast signal to an area where the broadcast signal from the satellite cannot be received within the service area.

By doing so, there is no fear that the direct broadcast signal transmitted from the satellite and the relay broadcast signal transmitted by the gap filler device cause interference. For this reason,
Even if the receiving device is near the boundary between the area where the direct broadcast signal from the satellite can be received and the area where the relay broadcast signal from the gap filler device can be received, the reception quality is kept high without being affected by interference. be able to.

On the other hand, the gap filler device of the present invention is a first filler for receiving a broadcast signal transmitted from a satellite.
Antenna, a radio circuit unit for at least amplifying a broadcast signal received by the first antenna and outputting a transmission broadcast signal having the same frequency as the received broadcast signal, and a radio circuit output from the radio circuit unit And a second antenna for wirelessly transmitting the transmission broadcast signal to an area where the broadcast signal from the satellite cannot be received in the service area.

By using such a gap filler device, as described above, each user behind a building can receive information from a satellite relatively easily and inexpensively without laying a coaxial cable or an optical cable. In addition, not only fixed stations but also mobile stations can receive information from satellites. Furthermore, since the relay broadcast signal to be transmitted to the shadow of the building is transmitted at the same frequency as the direct broadcast signal from the satellite, the user only needs to have a receiver to receive the direct wave from the satellite, and the relay broadcast signal from the gap filler device Signals can also be received.

In another satellite broadcasting system of the present invention, first and second satellites are arranged at a predetermined distance on the same satellite orbit, and the same service is provided from the first and second satellites. The same broadcast signal is transmitted to the area in synchronization with each other.

[0015] By doing so, the same broadcast signal is transmitted from two satellites at different positions to users in the service area. For this reason, for example, a station that is located in an area where a broadcast signal from one satellite cannot be directly received, such as a building shadow, can receive a broadcast signal from the other satellite. The same effect as the case where the gap filler device described in (1) is provided can be obtained.

When a spare device is arranged in the same orbit, this spare device is used as a second satellite. In this way, there is no need to launch a new satellite to take measures against building shadows and the like, and an inexpensive system can be provided.

Further, in the satellite broadcasting system according to the present invention, in a satellite, a broadcast signal transmitted from a terrestrial broadcast station is converted into first and second broadcast signals having different frequencies from each other and wirelessly transmitted, and the gap filler is provided. The apparatus receives a second broadcast signal transmitted from the satellite, converts the second broadcast signal into a third broadcast signal having the same frequency as the first broadcast signal, and converts the third broadcast signal into a third broadcast signal. Is transmitted wirelessly to an area where the first broadcast signal from the satellite cannot be received in the service area.

By doing so, in the gap filler device, the frequency of the second broadcast signal received from the satellite is different from the frequency of the third broadcast signal transmitted by the device itself. It is possible to easily prevent wraparound.

Further, the broadcast receiving apparatus may have means for receiving and synthesizing the first broadcast signal transmitted from the satellite and the third broadcast signal transmitted by the gap filler apparatus, respectively. With this configuration, the broadcast receiving apparatus can perform higher quality reception when the broadcast receiving apparatus is located at a place where both the first broadcast signal from the satellite and the third broadcast signal from the gap filler apparatus can be received. Become.

Further, the satellite conversion means converts the broadcast signal transmitted from the terrestrial broadcast station into a first broadcast signal in the S band and a second broadcast signal in a higher frequency range than the S band. A signal may be transmitted as a signal for the broadcast receiving device, and the second broadcast signal may be transmitted as a signal for the gap filler device.

[0021] In this case, since the broadcast receiving device only needs to receive the S-band broadcast signal, it is possible to receive the broadcast signal with simple equipment without using a large antenna such as a parabolic antenna. For this reason, the user can use a small and inexpensive broadcast receiving apparatus, and can receive a broadcast with inexpensive facilities without sacrificing portability. On the other hand, in the gap filler device, for example, a broadcast signal in the Ku or Ka band is received, so a receiving facility having a parabolic antenna is required, and a frequency conversion function from the Ku or Ka band to the S band is required. However, since the gap filler device is a part of the equipment of the system, it does not burden the user and does not pose a major problem.

Further, the satellite broadcasting system of the present invention includes a terrestrial network transmission means for transmitting, via a terrestrial network, a second broadcast signal having the same content as the first broadcast signal transmitted from the terrestrial broadcast station to the satellite, Receiving the second broadcast signal transmitted by the terrestrial network transmission means, converting the received second broadcast signal into a third broadcast signal in the same frequency band as the broadcast signal transmitted by the satellite, And a gap filler device for wirelessly transmitting the broadcast signal of No. 3 to an area where the broadcast signal from the satellite cannot be received in the service area.

Further, the gap filler device of the present invention comprises:
Terrestrial network receiving means for receiving a second broadcast signal having the same content as a broadcast signal transmitted from the terrestrial broadcast station to the satellite from the terrestrial broadcast station via a terrestrial network; Converting means for converting the obtained second broadcast signal into a third broadcast signal having the same frequency band as the broadcast signal transmitted by the satellite; and converting the third broadcast signal obtained by the conversion means into the service area. Transmitting means for wirelessly transmitting a broadcast signal from the satellite to an area where reception is impossible.

By using such a system and the gap filler device, even when the gap filler device cannot be installed in a place where a direct broadcast signal can be received from a satellite due to location conditions or the like, a broadcast signal from a satellite cannot be directly received. The dead area can be reliably covered.

Further, the gap filler device is provided with satellite receiving means for receiving a broadcast signal transmitted from a satellite, and a second broadcast signal having the same content as a broadcast signal transmitted from the terrestrial broadcast station to the satellite. Terrestrial network receiving means for receiving via the upper network, and converting the second broadcast signal received by the terrestrial network receiving means into a third broadcast signal in the same frequency band as the broadcast signal transmitted from the satellite Conversion means for selecting one of the broadcast signal received by the satellite reception means and the third broadcast signal obtained by the conversion means, and Selective transmission means for wirelessly transmitting a broadcast signal to an unreceivable area.

With this configuration, the function of receiving and relaying a broadcast signal from a satellite and the function of receiving and relaying a broadcast signal transmitted via a terrestrial network are provided to one gap filler device. Respectively, so that only one gap filler device is prepared,
Each of the above functions can be selectively used according to the installation conditions of the gap filler device.

In the above-mentioned selective transmitting means, it is determined whether or not a broadcast signal of a predetermined level or more is received by the satellite receiving means, and if it is determined that the broadcast signal is received, the broadcast signal received by the satellite receiving means is determined. Is selected and wirelessly transmitted to the unreceivable area. If it is determined that the broadcast signal is not received, the third broadcast signal obtained by the conversion means is wirelessly transmitted to the unreceivable area.

According to this configuration, each function can be automatically selected according to whether or not a broadcast signal from a satellite can be directly received, and work such as maintenance setting can be facilitated.

The satellite broadcasting system of the present invention further comprises a monitoring device connected to the gap filler device via a communication line in addition to the gap filler device. Monitor information transmitting means for generating the monitor information to be represented and transmitting the monitor information to the monitoring device via the communication line, and the monitoring device includes a monitor transmitted from the gap filler device via the communication line. The information processing apparatus further comprises means for receiving information and performing predetermined processing for monitoring the operation state of the gap filler device based on the received monitor information.

With such a system, it is possible to centrally manage the operation state of the gap filler device, for example, at a monitoring center, thereby enabling quick response to a failure.

The following can be considered as a method of monitoring the monitor information. That is, in the first method, the monitoring device transmits a monitor information transmission request to the gap filler device via the communication line periodically or when necessary, and the monitor information is stored in the gap filler device, and Each time a transmission request arrives from the monitoring device, the stored monitor information is read out and transmitted to the monitoring device. With this method, even when there are a large number of gap filler devices, monitor information of these gap filler devices can be efficiently collected at the monitoring center.

In the second method, the gap filler device monitors the operation state of the device itself, and when it is detected that an abnormality has occurred in the operation state of the device itself, transmits monitor information indicating the content to the communication line. Is transmitted to the monitoring device via the. According to this method, when a failure occurs in the gap filler device, the information can be immediately notified to the monitoring center.

Further, when it is detected in the gap filler device that an abnormality has occurred in the operation state of its own device, message information to that effect is generated, and this message information is broadcast in an area covered by its own device. You may make it transmit to a receiver. In this way, when the gap filler device cannot receive a broadcast signal from, for example, a satellite, or when a failure occurs in its own device and the relay broadcast cannot be performed, a message to that effect is transmitted to the broadcast receiving device. Can be displayed. As a result, the user can clearly know the reason why reception is not possible.

Further, in addition to the gap filler device, the satellite broadcasting system of the present invention has a monitor receiving device having a function of receiving a received broadcast signal transmitted from the gap filler device in an unreceivable area, and the monitor receiving device. A monitoring device connected to the device via a communication line. And in the gap filler device,
Generates monitor information indicating the operation state of the own device and wirelessly transmits this monitor information included in the received broadcast signal, and the monitor receiving device receives the relay broadcast signal transmitted from the gap filler device and includes therein While extracting the monitor information from the, detecting the reception state of the relay broadcast signal, transmitting the detection information of the reception state and the extracted monitor information to a monitoring device via a communication line, the monitoring device, The monitor information and the detection information transmitted from the monitoring receiver via the communication line are received, and a predetermined process for monitoring the operation state of the gap filler device is performed based on the received monitor information and the detection information. It is characterized by having made it.

In such a system, the receiving state of the broadcast signal from the gap filler device can be directly observed by installing the monitoring receiver at an arbitrary place in the blind area, and the observation result is obtained. Can be sent to the monitoring center together with the monitor information transmitted by the gap filler device itself. For this reason, it is possible to perform monitoring that is more realistic.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) This satellite broadcasting system comprises a plurality of terrestrial broadcasting stations (VSAT) BC1, BC2 or feeder link stations, a geostationary satellite SAT1, and a satellite tracking control station STC.
C.

A terrestrial broadcasting station (VSAT) BC1, BC2 or a feeder link station transmits program information created and edited by each broadcasting company to the Ka band (26.5 to 40GH).
z) or Ku band (12.5 to 18 GHz) via the upstream transmission path to the geostationary satellite SAT1.

The geostationary satellite SAT1 has a Ka-band or Ku-band antenna having a diameter of, for example, 2.5 m, and an S-band (for example, 2.6G) having a diameter of 15 m.
Hz) antenna. The broadcast signal multiplexed from each of the broadcasting stations (VSAT) BC1 and BC2 or the feeder link station is received and amplified by the Ka or Ku band antenna, and then converted to an S band signal. Then, the converted broadcast signal is transmitted from the S band antenna to the service area via the S band downlink transmission path. The above geostationary satellite SAT
The diameter of the uplink transmission antenna mounted on the antenna 1 may be smaller than the 2.5 m class, and the diameter of the S band antenna is not limited to the 15 m class but may be the 8 m class.

The satellite tracking control station STCC monitors and controls the operation state of the geostationary satellite SAT1.

In the service area, for example, a broadcast receiver (not shown) fixedly installed in an office or home,
An in-vehicle or portable movable broadcast receiving apparatus MS receives a broadcast signal transmitted from the geostationary satellite SAT1 to an S-band downlink transmission path. In the S-band downlink transmission path, a plurality of channels having a transmission rate of 64-256 Kbps / channel are multiplexed at a maximum of 900 channels. When a video signal is transmitted by each channel, MPEG4 (moving picture e) is used as a video encoding method.
xperts group 4) is used.

In the system of the first embodiment, the gap filler device GFa is mounted on the roof of a high-rise building or the like.
Is installed. After receiving and amplifying the broadcast signal from the geostationary satellite SAT1, the gap filler device GFa keeps the received broadcast signal at the same frequency and in an area such as behind a building where the broadcast signal from the geostationary satellite SAT1 cannot be received. And is re-transmitted, for example, as follows.

FIG. 2 is a circuit block diagram showing the configuration. That is, the broadcast signal transmitted from the geostationary satellite SAT1 is received by the receiving antenna 11, and then input to the input filter 12, where only a predetermined transmission band is selected and then amplified by the low noise amplifier 13. The amplified broadcast signal is amplified by a power amplifier 14 and further band-limited to a predetermined transmission band by an output filter 15, and then transmitted from a transmitting antenna 16 to a geostationary satellite SA such as a building shadow.
It is transmitted to a dead area where the direct wave from T1 does not reach. Here, a directional antenna is used as the output antenna 16, which limits the transmission range of the broadcast signal to an insensitive area where direct waves from the geostationary satellite SAT1 cannot be received.

With such a configuration, broadcast signals transmitted from a plurality of broadcast stations BC1 and BC2 or feeder link stations are transmitted to the geostationary satellite SAT1 via the Ka or Ku band uplink transmission path. This geostationary satellite SA
The signal is transmitted from T1 to the service area via the S-band downlink transmission path, and is received by the broadcast receiver MS existing in the service area. At this time, since the geostationary satellite SAT1 is equipped with a large-diameter S-band antenna of 15m class and the S-band has a property of being hardly affected by rain attenuation, each broadcast receiver MS broadcasts the signal. The signal is received with a sufficiently large reception field strength. Therefore, the broadcast receiving apparatus MS can receive a broadcast signal by using a small rod antenna or a flat antenna.

However, a geostationary satellite S such as a building shadow
The broadcast receiving apparatus MS located in the dead area where the direct wave from the AT 1 cannot be received cannot directly receive the broadcast signal. However, the broadcast signal transmitted from the geostationary satellite SAT1 is received by the gap filler device GFa and then relayed and transmitted to the blind area behind the building. For this reason, the broadcast receiving device M located behind the building
In S, the broadcast signal can be received.

At this time, the gap filler device GF
The frequency of the broadcast signal relayed and transmitted from the satellite a
It is set the same as the broadcast signal sent from AT1.
For this reason, even when the broadcast receiving apparatus MS is behind a building,
As long as there is only a receiver that receives a broadcast signal from the geostationary satellite SAT1 without using a special receiver, the broadcast signal from the gap filler device GFa can be received.

In addition, a broadcast signal is transmitted from the gap filler device GFa to a blind area behind a building by using a directional antenna to limit a broadcast range.
For this reason, despite the fact that the frequency of the signal transmitted from the gap filler device GFa is set to be the same as the signal frequency transmitted from the geostationary satellite SAT1, the frequency of the signal from the geostationary satellite SAT1 around the blind area behind the building is reduced. There is little fear that the transmission signal of the gap filler device GFa will interfere with the signal, so that the broadcast receiving device MS can receive the broadcast signal with high quality regardless of the area.

(Second Embodiment) Generally, when a radio signal is transmitted from a geostationary satellite arranged in a geosynchronous orbit above the equator, a radio wave is shadowed on the north side of an obstacle such as a building on the ground. The second embodiment of the present invention pays attention to this point and, in an area where a number of buildings are arranged, relays a broadcast signal with directivity in the east-west direction from the gap filler device. is there.

FIGS. 3 and 4 are diagrams for explaining this embodiment. That is, in a place where buildings stand along a road, such as a downtown area or an office district, a dead area where the radio signal from the geostationary satellite SAT1 cannot be directly received is shaded on the north side by these buildings. As shown by, it is formed in a strip shape in the east-west direction.

Therefore, in this embodiment, the gap filler device GFb is installed at a position where a broadcast signal from the geostationary satellite SAT1 can be directly received, for example, at a large intersection. As a means for installing the support, for example,
5 and the gap filler device G is provided on the support 45.
This is performed by fixing Fb.

The gap filler device GFb has a main body 4 containing a transmitting / receiving circuit section such as a low noise amplifier and a power amplifier.
2 and an antenna 41 for receiving a broadcast signal from the geostationary satellite SAT is mounted on an upper part of the main body 42.
Antennas 43 and 44 for retransmission are attached to two opposite side surfaces of the main body 42, respectively. The directions of the retransmission antennas 43 and 44 are set so that the transmission direction of the retransmission radio signal is east-west.

In the case where an existing support such as a support for a road sign, a support for a signal, and a telegraph pole installed on a sidewalk or the like can be used, a dedicated support 45 is not provided and the existing support is used. May be provided with a gap filler device GFb.

As described above, according to the present embodiment, the broadcast signal transmitted from the geostationary satellite SAT1 is received and amplified by the gap filler device GFb and then transmitted from the relay transmitting antennas 43 and 44 to FIGS. As shown, it is transmitted with directivity in the east-west direction. Therefore, the gap area where the broadcast signal from the geostationary satellite SAT1 cannot be directly received can be effectively covered only by installing a small number of gap filler devices.

Note that the gap filler device GFb is not necessarily limited to a device in which the antenna 41 for satellite reception and the antennas 43 and 44 for retransmission are integrally attached to the main body 42. For example, the main body 42 to which the antenna 41 for satellite reception is attached is installed at a place where the signal from the geostationary satellite SAT1 can be more reliably received, such as the roof of a building, and the antennas 43 and 44 for relay transmission are connected at the intersection. The main body 42 and the antennas 43 and 44 for retransmission are connected via a coaxial cable. In this case, the connection between the main body 42 and the retransmission antennas 43 and 44 becomes slightly troublesome, but a gap filler device with high reception performance can be provided. In addition,
As the antennas 43 and 44, small patch antennas can be used.

In order to cover a wide range of the band-shaped dead area, for example, as shown in FIG. 5, a gap filler device GFc is installed at a high place such as the roof of a building, and directivity is provided from the roof to the dead area. It is good to send it with. FIG. 5 shows a case where this configuration covers a dead area of several tens to several kilometers.

Depending on the shape of the dead area, for example, as shown in FIG.
An Fd may be installed, and a broadcast signal may be relayed and transmitted from the gap filler device GFd using an omnidirectional antenna. In this way, a wide circular dead area can be covered.

(Third Embodiment) In a third embodiment of the present invention, a plurality of channel signals transmitted from a terrestrial broadcast station to a satellite are multiplexed by a CDM (Code Division Multiplex) method. The CDM multiplex broadcast signal arriving via a satellite is amplified and relay-transmitted to a gap area such as behind a building.

FIG. 7 is a circuit block diagram showing a configuration of a transmitting section in terrestrial broadcasting stations BC1 and BC2. Broadcast signals of a plurality of programs (N programs in the figure) edited by a circuit (not shown) are input to modulators 51 to 5n, respectively. In these modulators 51 to 5n, the broadcast signal is spread-spectrum-modulated by different spreading codes generated from spreading code generators 61 to 6n, respectively. The broadcast signals subjected to spread spectrum modulation by the modulators 51 to 5n are combined into one system of multiplex broadcast signals by a combiner 71 and then input to a modulator 72. In this modulator 72,
The multiplex broadcast signal is further modulated by a digital modulation scheme such as QPSK or QAM. Then, the modulated multiplexed broadcast signal is frequency-converted into a Ka or Ku band radio signal by the transmitter 73, further amplified to a predetermined transmission power, and transmitted from the antenna 74 to the geostationary satellite.

The geostationary satellites are the terrestrial broadcasting stations BC1, BC
2 or a CDM multiplex broadcast signal transmitted from the feeder link station is frequency-converted into an S band, amplified to a predetermined power level, and then transmitted to a terrestrial service area.

The gap filler device receives the CDM multiplex broadcast signal transmitted from the geostationary satellite, amplifies the received signal to a transmission power level for the gap filler, and transmits the signal to the dead area.

On the other hand, the broadcast receiving apparatus MS is configured as follows. FIG. 8 is a circuit block diagram showing a configuration of the broadcast receiving device MS. In the figure, a CDM multiplex broadcast signal transmitted from a geostationary satellite and a gap filler device is input to a receiver 22 after being received by an antenna 21. The receiver 22 receives and reproduces the broadcast signal corresponding to the channel designated by the user from the CDM multiplex broadcast signal by the RAKE receiving method, and inputs the reproduced received signal to the audio / video separation circuit unit 23.

The audio / video separation circuit unit 23 separates the reproduced reception signal into audio data, video data, and additional data including text data, and inputs the separated received audio data to the audio decoder 24. The received video signal is input to the video decoder 26, and the additional data is input to the additional data decoder 28. Audio decoder 24
Reproduces the audio signal by decoding the received audio data,
This voice signal is output from the speaker 25 as a loudspeaker. Further, the video decoder 26 decodes the received video data according to, for example, the MPEG4 system, and supplies the decoded video signal to the liquid crystal display 27 for display. Further, the additional data decoder 28 decodes the additional data composed of text data and the like, and displays the decoded data together with the video signal on the liquid crystal display 27.

The receiver 22 is configured as follows. FIG. 9 is a circuit block diagram showing the configuration. That is, the CDM multiplex broadcast signal arriving from the geostationary satellite and the gap filler device is first down-converted from the radio frequency to the baseband frequency by the radio circuit 28. The received baseband signal is digitized by an analog / digital converter (A / D) 29 at a predetermined sampling cycle, and thereafter, a search receiver 30 and three digital data demodulators 31, 3
2 and 33, respectively.

The search receiver 30 is connected to the terrestrial broadcasting stations BC1,
A pilot signal transmitted from the BC 2 is received and demodulated. Basically, each digital data demodulator 3
It has the same configuration as 1, 32 and 33.

The data demodulators 31, 32, and 33 rake the broadcast signal corresponding to the channel specified by the user from the CDM multiplex broadcast signal arriving from the geostationary satellite or the CDM multiplex broadcast signal arriving from the gap filler device.
The signal is demodulated by the receiving method.

That is, the data demodulators 31, 32, 33
Generate independent clocks based on the sampling clock of the A / D converter 29 and operate independently of each other by the unique clocks.
A clock tracking unit and a data demodulation unit are provided. Among them, the data demodulation units are phase compensation units 311, 321, 33
1, multipliers 312, 322, 332, PN code generators 313, 323, 333, accumulator 314,
324, 334.

In the phase compensators 311, 321, 331,
Phase compensation of the received signal is performed for path diversity. The multipliers 312, 322, and 332 multiply the reception signals output from the phase compensation units 311, 321, and 331 by the PN codes corresponding to the designated channels generated by the PN code generators 313, 323, and 333, Thus, the spectrum of the received signal is despread.
In accumulators 314, 324, and 334, the despread received signals output from multipliers 312, 322, and 332 are integrated, and the integrated outputs are input to symbol combiner 34, respectively.

The symbol synthesizer 34 reproduces a data component by synthesizing the integrated output of the received signals output from the digital data demodulators 31, 32 and 33, and converts the reproduced data component to the audio / audio data shown in FIG. It is supplied to the video separation unit 23.

The control unit 35 includes a microcomputer as a main control unit, and includes path position detecting means and PN code generation controlling means as control functions related to RAKE reception. The path position detecting means detects the geostationary satellite SA from the pilot signal received by the search receiver 2.
The path positions of the signal arriving from T and the signal arriving from the gap filler device are detected. The PN code generation control means calculates an optimum PN address value based on the detection result of the path position, and converts the PN address value into the PN code generators 313 and 313 of the three digital data demodulators 31, 32 and 33. 323 and 333. Thus, the chip phase of the PN code generated from each of the PN code generators 313, 323, 333 is variably controlled.

By using the broadcast receiving apparatus MS having such a configuration, a CDM multiplex broadcast signal transmitted from a geostationary satellite and a CDM multiplex broadcast signal retransmitted from a gap filler apparatus are received as if receiving a multipath signal. And can be received and reproduced and combined. That is, it is possible to receive path diversity reception of a CDM multiplex broadcast signal transmitted from a geostationary satellite and a CDM multiplex broadcast signal relay-transmitted from a gap filler device. For this reason, even when the broadcast receiving apparatus MS is located in an area where both the CDM multiplex broadcast signal from the geostationary satellite and the relay transmission signal from the gap filler apparatus can be received, high quality without interference between the two signals is obtained. Can be received.

Further, according to the present embodiment, there is no need to worry about interference due to the same frequency between the CDM multiplex broadcast signal from the geostationary satellite and the relay transmission signal from the gap filler device. There is no need to strictly adjust the directivity of the signal to be transmitted, which makes it possible to easily install the gap filler device.

(Fourth Embodiment) In a fourth embodiment of the present invention, two geostationary satellites, which are launched on the same geosynchronous orbit and are composed of a main unit and a spare unit, are separated at a predetermined interval. By arranging and transmitting the same broadcast signal from these geosynchronous satellites to the service area in synchronization with each other, even if the broadcast receiving apparatus MS is in an area where the broadcast signal from this unit cannot be received, the broadcast from the standby unit It is designed to receive broadcast signals.

FIG. 10 is a schematic configuration diagram of a satellite broadcasting system according to this embodiment. In the figure, two geostationary satellites SATa and SATb are arranged at a predetermined distance in a geosynchronous orbit. Each of the above geostationary satellites SATa, S
ATb is one that functions as the main unit and the other functions as the standby unit. Even when the main unit is functioning normally, the standby unit is not set to the standby state, and the same broadcast signal as the main unit is transmitted. I have.

With such a configuration, for example, as shown in FIG. 7, a mobile station MS located in an area where a broadcast signal RSa from the main unit SATa cannot be received by a building or the like receives a broadcast signal RSb from the standby unit SATb. can do. Conversely, the broadcast signal RS from the standby unit SATb
The mobile station MS located in the area where it cannot receive b
The broadcast signal RSa from Ta can be received. Therefore, according to the present embodiment, it is possible to eliminate the gap area without installing the gap filler device on the ground. Moreover, in the present embodiment, since the gap filler effect is realized by using the existing spare machine, there is no need to launch a new satellite, and there is an advantage that the satellite can be realized at low cost.

(Fifth Embodiment) In a fifth embodiment of the present invention, a broadcast signal transmitted by a terrestrial broadcast station or a feeder link station is transmitted to a geostationary satellite by a first broadcast for a broadcast receiving apparatus having different frequencies. Signal, and the second broadcast signal for the gap filler device is frequency-converted and transmitted,
In the gap filler device, the second broadcast signal is received, converted into a broadcast signal having the same frequency as the first broadcast signal, and then relayed and transmitted to an insensitive area.

FIG. 11 is a schematic configuration diagram of a satellite broadcasting system according to the present embodiment. FIG. 12 shows a configuration of a transponder mounted on the geostationary satellite SAT2 of this system, and FIG. 13 shows a configuration of a gap filler device.

In the transponder of the geostationary satellite SAT2,
A Ku-band uplink broadcast signal UL (frequency fua) transmitted from a terrestrial broadcast station BC is received by a receiving antenna 81, and then amplified by a low-noise amplifier 82.
Is input to In the signal distributor 83, the upstream broadcast signal is distributed to two systems.

The broadcast signal of one system is converted into an S-band radio frequency signal (frequency f) by a first frequency converter 84.
s), is amplified by the first power amplifier 86 to a transmission power level required for reception by the broadcast receiving device of the fixed station or the mobile station MS, and then is transmitted from the S-band transmission antenna 88 to the first power amplifier 86. Is transmitted to the service area on the ground as the downstream broadcast signal DLa.

On the other hand, the broadcast signal of the other system to which the signal has been distributed is frequency-converted by the second frequency converter 85 into a Ku-band radio frequency signal (frequency fub),
Is amplified to the transmission power level necessary for reception by the gap filler device GFe by the power amplifier 87 of FIG.
The signal is transmitted as the second downlink broadcast signal DLb from the u-band transmission antenna 89. The second downlink broadcast signal DLb and the uplink broadcast signal UL are both transmitted in the Ku band, but have different frequencies. For example, the frequency fub of the second downlink broadcast signal DLb is 14 GHz
And the frequency fua of the uplink broadcast signal UL is 12 GHz.
Is set to

On the other hand, the gap filler device GFe uses the second broadcast signal DL transmitted from the geostationary satellite SAT2.
b is received by the antenna 91 and then the low noise amplifier 92
And is input to the frequency converter 93. In the frequency converter 93, the received second downlink broadcast signal is converted into an S-band radio frequency signal (frequency fs), that is, the first downlink broadcast signal DLa transmitted by the geostationary satellite SAT2 to the broadcast receiver. The frequency is converted to a radio frequency signal of the same frequency. The broadcast signal frequency-converted to the S band is amplified by the power amplifier 94 to a transmission power level corresponding to the size of the gap filler cover area GE, and then transmitted from the transmission antenna 95 as a relay broadcast signal DLg. Area GE
Sent to

With such a configuration, the geostationary satellite SA
Since the frequency of the downlink broadcast signal DLb arriving from T2 is different from the frequency of the relay broadcast signal DLg transmitted to the gap filler cover area GE, the gap filler device GFe transmits the transmission relay broadcast signal DLg to the receiving antenna. The sneak path can be easily prevented, and thereby, isolation between input and output can be easily and reliably realized.

(Sixth Embodiment) In a sixth embodiment of the present invention, a second broadcast signal having the same content as an uplink broadcast signal transmitted from a terrestrial broadcast station to a geostationary satellite is transmitted via a terrestrial network to a gap. The same relay broadcast signal as the downstream broadcast signal transmitted from the geostationary satellite to the broadcast receiving device is generated based on the second broadcast signal transmitted through the terrestrial network in the gap filler device. Then, this is transmitted to the insensitive area.

FIG. 14 is a circuit block diagram showing the configuration. The terrestrial broadcast station (not shown) generates a second broadcast signal having the same content as the upstream broadcast signal transmitted to the geostationary satellite by itself and configured in a signal format for wired transmission,
This is transmitted to the gap filler device GFf via a terrestrial public network NW such as an ISDN network.

When the second filler signal from the terrestrial broadcasting station is received by the modem, the gap filler device GFf changes the signal format of the second broadcasting signal from the cable transmission format to the satellite broadcast signal in the signal converter 101. To the signal format. Then, this satellite transmission broadcast signal is frequency-converted into an S-band radio frequency signal by a frequency converter 102, and further a power amplifier 103
And amplifies it to a transmission power level corresponding to the size of the dead area, and uses the amplified signal as a relay broadcast signal for the transmitting antenna 10.
4 is transmitted to an insensitive area such as behind a building.

With such a configuration, even when the gap filler device cannot be installed at a place where a downstream broadcast signal from a geostationary satellite can be received, a broadcast signal can be reliably broadcast to an insensitive area.

The above-mentioned gap filler device GFf
In addition to the circuit for receiving a broadcast signal via the above terrestrial public network NW and generating a relay broadcast signal, it also receives a downlink broadcast signal from a geostationary satellite as shown in FIG. A circuit for conversion is provided. Then, according to the installation condition of the gap filler device, the broadcast signal generated by each of the above circuits may be selected and transmitted to the insensitive area.

Further, the apparatus further comprises a circuit for judging the reception quality of the downlink broadcast signal from the geostationary satellite, and when the judgment circuit determines that the downlink broadcast signal is received with the predetermined reception quality, The relay broadcast signal generated based on the downstream broadcast signal from the selected broadcast signal is selected and transmitted to the blind area. On the other hand, when it is determined that the predetermined reception quality cannot be obtained, the broadcast signal is transmitted via the terrestrial public network NW. The relay broadcast signal generated based on the second broadcast signal may be selected and transmitted to the blind area.

(Seventh Embodiment) In a seventh embodiment of the present invention, the gap filler device has a function of generating monitor information indicating the operation state of its own device and transmitting the monitor information to the monitor center. A monitor center monitors the operation state of the gap filler device based on the monitor information.

FIG. 15 shows a first example of the system according to this embodiment. In the figure, the gap filler device GFg detects elements representing the operation state of the own device such as the reception level of the downlink broadcast signal and the transmission level of the relay broadcast signal at fixed time intervals, and stores the information in the memory as information based on the elements. accumulate.

On the other hand, the monitor center MCa generates a transmission request for monitor information periodically or at an arbitrary timing, and sends this transmission request to the gap filler device GFg via the ground network NW. Then, the gap filler device GFg reads out the monitor information from the memory and transmits this to the monitor center MCa via the ground network NW. At this time, the monitor information to be transmitted to the monitor center MCa may be only the latest monitor information, or all the monitor information accumulated from the previous transmission timing to the current transmission timing may be transmitted. Good.

That is, the monitor center MCa collects monitor information from a plurality of gap filler devices scattered in the service area by the polling method, and displays or prints out the collected monitor information. At the same time, it is determined whether or not the operation state of the gap filler device is normal based on the contents of the monitor information, and the determination result is displayed.

With such a configuration, the operation state of each gap filler device GFg can be centrally managed in the monitor center MCa, and efficient maintenance can be performed. Further, since the monitoring information is collected by the polling method, it is possible to efficiently collect the monitoring information of many gap filler devices.

FIG. 16 shows a second example of the system according to this embodiment. In the figure, each gap filler device GFh and the monitor center MCb are connected via a satellite communication line. The gap filler device GFh reads the monitor information from the memory every time a monitor information transmission request arrives from the monitor center MCb via the satellite communication line, and converts the monitor information into a signal format for satellite communication. Thereafter, the signal is transmitted to the monitor center MCb via the satellite communication line.

According to such a configuration, monitor information can be collected from each gap filler device using the existing satellite communication line of the geostationary satellite, so that the communication line using the terrestrial network NW can be eliminated. .

In each of the examples described above, the monitor information of the gap filler devices GFg and GFh is transmitted to the monitor center M.
The case of collecting by polling from Ca and MCb has been described. However, in addition to the collecting function by polling, the gap filler devices GFg and GFh are provided with a self-judgment function of the operation state, and when an operation abnormality is detected, the monitor centers MCa and MCb are called from the gap filler devices GFg and GFh. Thus, the monitor information relating to the abnormality may be notified to the monitor centers MCa and MCb.

In this way, when an operation error occurs in the gap filler device, the monitor center can immediately know that the operation error has occurred, and as a result, it is possible to take a quicker recovery action.

Further, the gap filler devices GFg, G
If a reception error of a broadcast signal from a satellite or an operation error of the gap filler devices GFg, GFh themselves occurs in Fh, a message to that effect is sent to the monitor centers MCa, MCb.
May be transmitted to a broadcast receiving device existing in the dead area. At this time, a text message or a voice message such as "The reception condition from the satellite is deteriorating. Please wait for a while."

FIG. 17 shows a third example of the system according to this embodiment. In the figure, when generating and transmitting a relay broadcast signal based on a downlink broadcast signal arriving from a geostationary satellite, the gap filler apparatus GFi multiplexes monitor information indicating the operation state of the apparatus itself with the relay broadcast signal. To the blind area. As a multiplexing method, an FDM method or a CDM method can be used.

A monitor receiver MR is arranged at an arbitrary position in the dead area, for example, at a position corresponding to the edge of the area. This monitor receiver MR may be a handy type carried by a maintenance person, a vehicle-mounted type, or a fixedly installed type. The monitor receiver MR is provided with the gap filler device GFi.
And receives and separates and extracts the monitor information, and detects the reception level of the relay broadcast signal. Then, the detection data of the reception level is included in the monitor information, and the monitor information is transmitted to the monitor center MCc via a mobile communication network INW such as a cellular radio telephone system or a PHS.

With this configuration, the detection data of the reception level actually measured by the monitoring receiver MR can be transmitted to the monitor center MCc together with the monitor information generated by the gap filler device. For this reason,
The monitor center MCc can determine not only the operation state of the gap filler device itself but also the suitability of the transmission level and the actual reception level in the blind area.

The present invention is not limited to the above embodiments. For example, by using a method of installing a gap filler device on the ground to cover a dead area and a method of using two geostationary satellites to cover a dead area, an area that cannot be covered by each other's method is used. May be covered.

In each of the above embodiments, a satellite broadcasting system using a geostationary satellite is taken as an example, and a broadcast signal transmitted from a geostationary satellite is received by the gap filler device and retransmitted to the broadcast receiving device MS. However, the present invention is not limited to this. For example, in an interactive satellite broadcasting system, a signal transmitted from the broadcast receiver MS to the satellite may be relayed by a gap filler device and transmitted to the satellite.

Further, in the above-described embodiment, a case has been described as an example in which a blind area generated behind a building is covered.
The present invention can be similarly applied to cover a gap area caused by another building such as a steel tower or a natural object such as a mountain or a cliff.

Further, the present invention can be applied to a case where a blind area in a room is covered. For example, a small indoor gap filler device (repeater) is installed at a position where a downstream broadcast signal from a satellite can be directly received, such as near a window, and a relay broadcast signal is transmitted from the repeater to the room and received by the receiver. Let it. In this case, the receiving device may be connected to the repeater via a coaxial cable or the like, and the received downstream broadcast signal may be transmitted to the receiving device via the coaxial cable. Further, the repeater may be installed on the roof or roof of a building or house.

In addition, the configuration and installation location of the gap filler device, the type and configuration of the broadcast receiving device MS, the type of satellite,
The type of signal transmitted from the satellite and the transmission method thereof can be variously modified without departing from the scope of the present invention.

[0105]

As described in detail above, according to the present invention,
Providing a gap filler device, the gap filler device receives a broadcast signal relayed by a satellite, and transmits the received broadcast signal from the satellite to an area in a service area where a broadcast signal from the satellite cannot be received. By transmitting radio signals at the same frequency as the broadcast signal to be transmitted, it is not necessary to install large-scale equipment in blind areas, such as behind buildings, where radio signals from satellites cannot be received directly. It is possible to provide a satellite broadcasting system and a gap filler device capable of realizing an inexpensive and effective gap filler by reliably receiving even an MS.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a satellite broadcasting system having a gap filler function according to the present invention.

FIG. 2 is a circuit block diagram showing a configuration of a gap filler device used in the system shown in FIG.

FIG. 3 is a plan view illustrating a second embodiment of the satellite broadcasting system according to the present invention.

FIG. 4 is a front view for explaining a second embodiment of the satellite broadcasting system according to the present invention.

FIG. 5 is a diagram showing another example of the second embodiment of the satellite broadcasting system according to the present invention.

FIG. 6 is a diagram showing another example of the second embodiment of the satellite broadcasting system according to the present invention.

FIG. 7 is a circuit block diagram showing a configuration of a transmitting unit of a terrestrial broadcasting station used in a third embodiment of the satellite broadcasting system having a gap filler function according to the present invention.

FIG. 8 is a circuit block diagram showing a configuration of a broadcast receiving device used in a third embodiment of a satellite broadcast system having a gap filler function according to the present invention.

9 is a circuit block diagram showing a configuration of a receiver of the broadcast receiving device shown in FIG.

FIG. 10 is a schematic configuration diagram showing a fourth embodiment of a satellite broadcasting system having a gap filler function according to the present invention.

FIG. 11 is a schematic configuration diagram showing a fifth embodiment of a satellite broadcasting system having a gap filler function according to the present invention.

FIG. 12 is a circuit block diagram showing a configuration of a transponder of a geostationary satellite used in the system shown in FIG. 11;

13 is a circuit block diagram showing a configuration of a gap filler device used in the system shown in FIG.

FIG. 14 is a schematic configuration diagram showing a sixth embodiment of a satellite broadcasting system having a gap filler function according to the present invention.

FIG. 15 shows a first embodiment of the seventh embodiment of the satellite broadcasting system having a gap filler function according to the present invention.
The schematic block diagram which shows the Example of FIG.

FIG. 16 shows a second embodiment of the seventh embodiment of the satellite broadcasting system having a gap filler function according to the present invention.
The schematic block diagram which shows the Example of FIG.

FIG. 17 shows a third embodiment of the seventh embodiment of the satellite broadcasting system having a gap filler function according to the present invention.
The schematic block diagram which shows the Example of FIG.

[Explanation of symbols]

BC, BC1, BC2: terrestrial broadcasting station (VSAT) SAT1, SAT2, SATa, SATb: geostationary satellite MS: mobile station MR: monitoring receiver GFa to GFi: gap filler device MCa to MCc: monitor center NW: terrestrial public network INW mobile communication network 11, 41, 81, 91 satellite reception antenna 12 input filter 13, 82, 92 low noise amplifier 14, 86, 87, 94, 103 power amplifier 15 output filter 16, 43 , 44, 88, 89, 95, 104 ... antenna for transmission 42 ... main body for gap filler device 45 ... support column for fixing the gap filler device 20 ... control unit 21 ... reception antenna of fixed station or mobile station 22 ... receiver 23 ... Audio / video separation circuit section 24 ... Audio decoder 25 ... Speaker 26 ... Video decoder 27 ... Liquid Display 28 ... Wireless circuit 29 ... Analog / digital converter (A / D) 30 ... Search receiver 31,32,33 ... Digital data demodulator 34 ... Symbol synthesizer 35 ... Control unit 36 ... Additional data decoder 311,321, 331, phase compensators 312, 322, 332, multipliers 313, 323, 333, PN code generators 314, 324, 334, accumulators 84, 85, 93, 102, frequency converters 101, signal converters

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Koishi 1 Koga Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Komukai Plant of Toshiba Corp. No. 1 in the Komukai Plant of Toshiba Corporation

Claims (20)

[Claims] 1. A satellite broadcasting system that broadcasts a broadcast signal transmitted by a terrestrial broadcast station by a satellite and broadcasts the broadcast signal to a predetermined service area on the ground, comprising: receiving a broadcast signal relayed by the satellite; A satellite broadcast comprising a gap filler device for wirelessly transmitting at the same frequency as a broadcast signal transmitted from the satellite to an area where a broadcast signal from the satellite cannot be received in the service area. system 2. The gap filler device has a directional antenna, and the directional antenna directs the received broadcast signal to an area where the broadcast signal from the satellite cannot be received in the service area. 2. The satellite broadcast system according to claim 1, wherein the satellite broadcast is transmitted wirelessly. 3. When the satellite is a geostationary satellite arranged in a geosynchronous orbit above the equator, the gap filler device wirelessly transmits the received broadcast signal with directivity in east-west directions. The satellite broadcasting system according to claim 2, wherein 4. At least one of the terrestrial broadcasting station and the satellite has a modulating means for transmitting a broadcast signal by performing spread spectrum modulation using a predetermined spreading code, and the gap filler device transmits the broadcast signal from the satellite. A satellite broadcast system, comprising: receiving a spread spectrum modulated broadcast signal; and wirelessly transmitting the received broadcast signal to an area in the service area where a broadcast signal from the satellite cannot be received. 5. A gap filler device used in a satellite broadcast system for transmitting a broadcast signal to a predetermined terrestrial service area via a satellite, wherein a first signal for receiving the broadcast signal transmitted from the satellite is provided.
An antenna, a radio circuit unit for at least amplifying a broadcast signal received by the first antenna and outputting a transmission broadcast signal having the same frequency as the received broadcast signal, and a radio circuit output from the radio circuit unit A gap filler device, comprising: a second antenna for wirelessly transmitting a transmission broadcast signal to an area where a broadcast signal from the satellite cannot be received in the service area. 6. When the satellite is a geosynchronous satellite arranged in a geosynchronous orbit above the equator, the second antenna wirelessly transmits a transmission broadcast signal with directivity in east-west directions. The gap filler device according to claim 5, wherein: 7. A first satellite arranged on a predetermined orbit and transmitting a broadcast signal transmitted from a terrestrial broadcasting station to a predetermined service area on the ground, and a predetermined satellite on the same orbit as the first satellite. And a second satellite for transmitting the same broadcast signal to the service area in synchronization with the broadcast signal transmitted by the first satellite toward the service area. Satellite broadcasting system. 8. The satellite broadcasting system according to claim 7, wherein a spare device of the first satellite is used as the second satellite. 9. A satellite for relaying a broadcast signal transmitted from a terrestrial broadcast station and transmitting the broadcast signal to a predetermined terrestrial service area; and receiving and reproducing the broadcast signal relayed by the satellite in the service area. And a plurality of broadcast receiving apparatuses having a function of receiving broadcast signals relayed by the satellite and transmitting the received broadcast signals to an area where the broadcast signals from the satellites cannot be received in the service area. A gap filler device, wherein the satellite is provided with a conversion unit that converts a broadcast signal transmitted from a terrestrial broadcast station into first and second broadcast signals having different frequencies from each other and wirelessly transmits the first and second broadcast signals, respectively, The apparatus receives a second broadcast signal transmitted from the satellite and converts the second broadcast signal into a third broadcast signal having the same frequency as the first broadcast signal. A satellite broadcasting system comprising: means for converting; and means for wirelessly transmitting the third broadcast signal to an area where the first broadcast signal from the satellite cannot be received in the service area. . 10. The satellite broadcast system according to claim 9, wherein said broadcast receiving apparatus further comprises means for receiving and combining said first broadcast signal and said third broadcast signal, respectively. 11. The satellite converting means converts a broadcast signal transmitted from a terrestrial broadcast station into an S-band first broadcast signal and an S-band broadcast signal.
Converting a second broadcast signal into a second broadcast signal in a higher frequency band than the band, transmitting the first broadcast signal as a signal for the broadcast receiving device, and transmitting the second broadcast signal as a signal for the gap filler device; The satellite broadcasting system according to claim 9, wherein: 12. A satellite broadcasting system for transmitting a broadcast signal transmitted by a terrestrial broadcast station to a predetermined terrestrial service area by relaying the broadcast signal through a satellite, comprising: a first broadcast signal transmitted from the terrestrial broadcast station to the satellite; Terrestrial network transmission means for transmitting a second broadcast signal having the same content via a terrestrial network, receiving a second broadcast signal transmitted by the terrestrial network transmission means, and transmitting the received second broadcast signal It converts to a third broadcast signal in the same frequency band as the broadcast signal transmitted by the satellite, and wirelessly transmits the third broadcast signal to an area in the service area where the broadcast signal from the satellite cannot be received A satellite broadcasting system comprising a gap filler device. 13. A gap filler device used in a satellite broadcasting system for relaying a broadcast signal transmitted by a terrestrial broadcast station by a satellite and transmitting the broadcast signal to a predetermined service area on the ground, wherein the terrestrial broadcast station transmits the signal to the satellite Terrestrial network receiving means for receiving a second broadcast signal having the same content as the broadcast signal to be transmitted from the terrestrial broadcasting station via a terrestrial network; and transmitting the second broadcast signal received by the terrestrial network receiving means to the Converting means for converting into a third broadcast signal in the same frequency band as the broadcast signal transmitted by the satellite; receiving the broadcast signal from the satellite in the service area, the third broadcast signal obtained by the converting means; A transmission unit for wirelessly transmitting to an impossible area. 14. A gap filler device used in a satellite broadcasting system for relaying a broadcast signal transmitted by a terrestrial broadcast station by a satellite and transmitting the broadcast signal to a predetermined service area on the ground, wherein a broadcast signal transmitted from the satellite is received. Satellite receiving means for receiving, via a terrestrial network, a second broadcast signal having the same content as a broadcast signal transmitted by the terrestrial broadcast station to the satellite; Converting means for converting the second broadcast signal received by the means into a third broadcast signal in the same frequency band as the broadcast signal transmitted from the satellite; a broadcast signal received by the satellite receiving means; One of the third broadcast signals obtained by the conversion means is selected to direct the broadcast signal from the satellite to an unreceivable area within the service area. Gap filler apparatus characterized by comprising a selected transmission means for transmitting. 15. The selective transmitting means determines whether or not a broadcast signal of a predetermined level or more is received by the satellite receiving means, and if it is determined that the broadcast signal is received, the broadcast received by the satellite receiving means. Selecting a signal and wirelessly transmitting the signal to the unreceivable area, and if it is determined that the signal is not received, wirelessly transmitting the third broadcast signal obtained by the conversion unit to the unreceivable area. The gap filler device according to claim 14, wherein 16. A satellite broadcasting system for relaying a broadcast signal to a predetermined service area on the ground by relaying the broadcast signal to a satellite, receiving a broadcast signal relayed by the satellite, and transmitting the received broadcast signal within the service area. A gap filler device that wirelessly transmits a broadcast signal from a satellite to an area where reception is not possible, and a monitoring device that is connected to the gap filler device via a communication line. Monitor information transmitting means for generating monitor information indicating the operation state of the monitor device and transmitting the monitor information to the monitoring device via the communication line, wherein the monitoring device is connected to the gap filler device via the communication line. Receiving the transmitted monitor information and monitoring the operation state of the gap filler device based on the received monitor information; Satellite broadcast system, characterized in that it comprises means for performing a predetermined processing order. 17. The monitoring device, comprising: means for transmitting a monitor information transmission request to the gap filler device via the communication line periodically or when necessary, wherein the monitor information transmission means of the gap filler device comprises: 17. The apparatus according to claim 16, further comprising: means for accumulating monitor information; and means for reading out the monitor information each time a transmission request comes from the monitoring device and transmitting the same to the monitoring device.
The satellite broadcasting system as described. 18. A monitor information transmitting unit of the gap filler device, wherein the monitor information transmitting unit monitors an operation state of the device itself, and when the device detects that an abnormality has occurred in the operation state of the device, the monitor information transmission unit transmits the content of the abnormality. 17. A satellite broadcasting system according to claim 16, further comprising means for transmitting the monitor information to the monitoring device via a communication line. 19. The monitor information transmitting means of the gap filler device monitors the operation state of the device itself, and when the device detects that an abnormality has occurred in the operation state of the device itself, 17. The satellite broadcasting system according to claim 16, further comprising: means for generating the message information and transmitting the message information to a broadcast receiving device in an area covered by the own device. 20. A satellite broadcasting system for broadcasting a broadcast signal to a predetermined service area on the ground by relaying the broadcast signal to a satellite, receiving a broadcast signal relayed by the satellite, and transmitting the received broadcast signal in the service area. A gap filler device for wirelessly transmitting a broadcast signal from a satellite to an unreceivable area; and a monitor installed in the unreceivable area and having a function of receiving a received broadcast signal transmitted from the gap filler device. A receiving device, and a monitoring device connected to the monitoring receiving device via a communication line, wherein the gap filler device generates monitor information indicating an operation state of the device itself, and transmits the monitor information to the monitor device. Means for wirelessly transmitting the received broadcast signal, the monitor receiving device comprising: Means for receiving a transmitted signal and extracting the monitor information therefrom; means for detecting a reception state of the received broadcast signal; and transmitting the extracted monitor information and the detection information of the reception state via the communication line. Means for transmitting to the monitoring device, the monitoring device receives the monitor information and the detection information transmitted from the monitor receiving device via the communication line, and transmits the received monitor information and the detection information. A satellite broadcast system comprising means for performing a predetermined process for monitoring an operation state of the gap filler device based on the information.