JP3379366B2 - Relay broadcast device and broadcast receiving device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relay broadcasting device for receiving, amplifying and transmitting a radio signal from a transmitting station, particularly a TV signal from a television (hereinafter referred to as "TV") broadcasting station, and a relayed TV signal. The present invention relates to a broadcast receiving device for receiving.

[0002]

2. Description of the Related Art FIG. 13 is a block diagram of a conventional relay broadcasting apparatus. In the figure, 1 is a receiving antenna having directivity for receiving a TV signal which is a radio signal, and 2 is this TV.
An input filter (3) for extracting a channel signal of a predetermined frequency from the signal outputs this channel signal to an intermediate frequency (hereinafter,
The receiving unit 4 which converts the frequency into an “IF (: Intermediate Frequency)” signal and outputs the IF signal
And a coupler 5, which is a signal branching unit for branching and outputting to the second IF signal, amplifies the first IF signal, and T
The transmitter 6 for frequency-converting and outputting again to the V signal, 6 is the T
Output filter for removing unnecessary spurious in V signal, 7
Is a transmitting antenna for transmitting a TV signal from which this unnecessary spurious is removed. Here, the input filter 2, the receiving unit 3, the coupler 4, the transmitting unit 5, and the output filter 6 constitute the relay broadcasting device main body 100.

Reference numeral 8 is a video IF filter for extracting an IF band video signal from the second IF signal, 9 is a level detector for detecting and outputting the level of the IF band video signal (hereinafter referred to as "video level"), Reference numeral 10 denotes a comparison / determination unit that compares the video level with a predetermined threshold level that has been set and outputs the determination result as a transmission unit control signal. Here, the video IF filter 8, the level detector 9, and the comparison and determination means 10
Constitutes the input detection means 200. Reference numeral 11 denotes a transmission control unit that outputs a transmission unit drive signal that controls driving / stopping of the transmission unit based on the determination result of the comparison determination unit 10.

Next, the operation of the relay broadcast apparatus will be described with reference to FIGS. Here, FIG. 14 is an explanatory diagram of a positional relationship between a broadcasting station and a relay broadcasting device for explaining the operation of the conventional relay broadcasting device. In FIG. 14, the receiving antenna 1 of the relay broadcasting device is oriented toward a desired broadcasting station (hereinafter, referred to as "desired station") in the broadcasting service area. When the desired station starts broadcasting, a TV signal from the desired station (hereinafter referred to as “desired wave”) is received by the receiving antenna 1, and its video level is detected by the level detector 9.
This video level is compared with a predetermined threshold level by the comparison and determination means 10, and the determination result "TV signal present" is output. Upon receiving this determination result, a transmission unit drive signal for driving the transmission unit 5 is output from the transmission control unit 11, and the transmission unit 5 is driven. As a result, the desired wave is amplified by the transmitting unit 5 and is again transmitted from the transmitting antenna 7.

On the other hand, when the desired station finishes broadcasting, the desired wave is not received.
The determination result "no TV signal" is output. Upon receiving this determination result, a transmission unit drive signal for stopping the transmission unit 5 is output from the transmission control unit 11, and the transmission unit 5 is stopped.

Setting of the threshold level will be described with reference to FIG. FIG. 15 is an explanatory diagram of input / output levels of the relay broadcasting device for explaining the operation of the conventional relay broadcasting device. In the figure, the horizontal axis represents the received electric field strength level (dB / μm) of the TV signal received by the receiving antenna 1.
v) and the vertical axis represents the transmission power level (W) of the TV signal transmitted from the transmission antenna 7. The received electric field strength level of the desired wave is affected by various propagation environments while propagating from the broadcasting station to the relay broadcasting apparatus, and fluctuates in an extremely wide range as shown in FIG. Therefore, the threshold level (converted to the received electric field strength level at the receiving antenna 1) is
It is set below the minimum value of the received field strength level of the desired wave. When the desired wave above the threshold level is received, it is transmitted again at the transmission power level Po.

Incidentally, in actual TV broadcasting, there are a plurality of broadcasting stations using the same channel even outside the broadcasting service area. These broadcasting stations are arranged discretely so that radio waves do not interfere with each other. However, due to the above-mentioned wide range level fluctuation of the TV signal and the relationship between the directivity direction of the receiving antenna 1 and the arrival direction of the TV signal, the relay broadcasting device is out of the broadcasting service area for broadcasting the same channel as the desired station. A TV signal of the same channel (hereinafter, referred to as "interference wave") other than a desired wave may be received from another broadcasting station (hereinafter, referred to as "interference station"), and may be affected.

The state of this interference will be described with reference to FIGS. As shown in FIG. 14, it is assumed that the interfering station is distant from the relay broadcasting apparatus in the same direction from the desired station. In this case, the reception electric field strength level of the interfering wave received by the reception antenna 1 is generally lower than the reception electric field strength level of the desired wave. However, since the level fluctuation occurs as described above, the interfering wave causes the level fluctuation in the range shown in FIG. 15, for example, and the received electric field strength level of the interfering wave exceeds the threshold level. Then, even if the desired wave does not exist, the relay broadcast apparatus determines that “TV signal is present” in the received interference wave by comparing and judging the video levels, drives the transmission unit 5, and retransmits the interference wave.

[0009]

Since the conventional relay broadcasting apparatus is configured as described above, for example, the relay broadcasting apparatus is driven even for an interfering wave having the same channel as the desired wave. There was the problem of retransmitting the jammer.

The present invention has been made in order to solve the above problems, and its main purpose is to obtain a relay broadcast apparatus and a broadcast receiving apparatus that do not drive against interfering waves other than the desired wave. .

[0011]

[0012]

[Means for Solving the Problems] Relay broadcasting according to the present invention
In the device, a receiving unit that receives a wireless signal from a broadcasting station and outputs an intermediate frequency signal, a transmitting unit that modulates the intermediate frequency signal with a modulation signal, amplifies and outputs the wireless signal, and the intermediate frequency signal. An input detecting means for detecting a video signal and outputting a transmission part control signal indicating that there is a TV signal when the level of the video signal exceeds a predetermined level that is not a signal; and the transmission part control signal. Sometimes a transmission control unit that drives the transmission unit to output the radio signal and a radio signal output from the transmission unit are detected, and based on the detection result, an identification indicating that the radio signal is from the broadcasting station And a modulation signal generation means for generating the modulation signal which is a notification content signal including a signal.

The first receiving antenna for receiving the wireless signal from the first broadcasting station, the second receiving antenna for receiving the wireless signal from the second broadcasting station, and the first receiving antenna A receiver that receives the received wireless signal and outputs an intermediate frequency signal, a transmitter that amplifies the intermediate frequency signal and outputs it as a wireless signal, and detects a video signal from the intermediate frequency signal, and the level of the video signal Is not signalless
The first input detecting means for outputting a first transmitter control signal indicating that there is a TV signal when the level exceeds the level of, and the level of the radio signal received by the first receiving antenna and the second signal. The radio signal received by the first receiving antenna is compared with the level of the radio signal received by the receiving antenna.
Second input detection means for outputting a second transmission unit control signal when the signal is larger, and driving the transmission unit when both the first and second transmission unit control signals are output ,
And a transmission control section for outputting a radio signal received by the first receiving antenna .

A first receiving antenna for directly receiving a radio signal from the first broadcasting station and a first receiving antenna for indirectly receiving the radio signal from the first broadcasting station via another relay broadcasting device . Two receiving antennas, a receiving unit that inputs the radio signal received by the first receiving antenna and outputs an intermediate frequency signal, a transmitting unit that amplifies the intermediate frequency signal and outputs the intermediate frequency signal, and the intermediate frequency Video signal is detected from the signal, and the level of this video signal is a predetermined level that is no signal
When a video signal is detected by the first input detecting means for outputting a first transmission unit control signal indicating that a TV signal is present when the signal exceeds the range and the radio signal received by the second receiving antenna, the video signal is detected. Predetermined level where signal level is not no signal
A second input detecting means for outputting a second transmission unit control signal indicating that a TV signal is present when the output signal exceeds the limit, and the transmission unit for outputting the first and second transmission unit control signals together. Radio driven and received by the first receiving antenna
And a transmission control unit for outputting a signal .

Further, a receiving section for receiving a radio signal from a broadcasting station and outputting an intermediate frequency signal, a transmitting section for modulating the intermediate frequency signal with a modulation signal and amplifying and outputting as a wireless signal, and the intermediate frequency. Video signal is detected from the signal
However, the level of this video signal is not a no signal
Transmitter control signal indicating that there is a TV signal when it exceeds the limit
An input detecting means for outputting the transmitting section control signal, driving the transmitting section when receiving the transmitting section control signal , detecting a transmitting control section for outputting the wireless signal, and detecting a wireless signal output from the transmitting section, And a modulation signal generating means for generating the modulation signal which is a notification content signal including an identification signal indicating a radio signal from a station and a monitoring item signal indicating a monitoring state in the relay broadcasting device.

[0016]

[0017]

DETAILED DESCRIPTION OF THE INVENTION

Embodiment 1. An embodiment of the relay broadcast apparatus according to the present invention will be described below. In the first embodiment, T
An identification signal for identifying a desired wave is added to a subcarrier control signal, which is one signal included in the audio signal of the V signal (for example, identification is performed by a sine wave signal of a predetermined level with a frequency of 100 Hz). Amplitude modulation (hereinafter referred to as "AM
(: Amplitude Modulation) ”) has been applied). On the other hand, an identification signal different from the desired wave is added to the interfering wave (for example, AM modulation is performed with a sine wave signal having a frequency of 300 Hz) or the identification signal is not added. A desired wave / interfering wave is identified by detecting the presence or absence of this specific identification AM signal.

FIG. 1 is a block diagram of a relay broadcast apparatus according to the first embodiment. In the figure, 1 to 10
Nos. 0 and 200 are the same as the configuration of the conventional relay broadcast apparatus shown in FIG. Note that, in FIG. 1, 10 is used as the first comparison determination means for convenience of description.
Reference numeral 11a denotes a transmission control unit that outputs a transmission unit drive signal that controls driving / stopping of the transmission unit based on the determination results of the first comparison determination unit 10 and a second comparison determination unit 17 described later.

Reference numeral 12 is a voice IF filter for extracting an IF band voice signal from the second IF signal, and 13 is voice demodulation of the IF band voice signal, and a baseband (hereinafter, "BB (:
BaseBand) ”) demodulator that outputs a band audio signal, 1
Reference numeral 4 is a subcarrier BB filter for extracting a subcarrier control signal from a BB band audio signal, 15 is an AM detector for detecting an amplitude component of this subcarrier control signal, and 16 is an identification AM signal included in this amplitude component. Identification signal extraction filter,
Reference numeral 17 denotes a second comparison / determination means for comparing the level of the identification AM signal with a predetermined threshold level that has been set and outputting a determination result. Here, the voice IF filter 12, the demodulator 13, the subcarrier BB filter 14, the AM detector 15, the identification signal extraction filter 16, and the second comparison / determination means 17 are:
The identification signal detection means 300, which is the second input detection means, is configured.

Next, the operation of the relay broadcast apparatus will be described with reference to FIGS. Figure 2 shows the BB of the audio signal in the TV signal.
It is explanatory drawing of the spectrum in a zone. In the figure, the horizontal axis represents frequency and the vertical axis represents level. However, in this spectrum, only the frequency has meaning, and the level is not exact. If fH = about 15.73 kHz (horizontal scanning frequency of TV), the spectrum of the audio signal has a main channel signal (0 to 15 kHz), a sub channel signal (16 kHz to 47 kHz, center frequency = 2 fH = about 3
1.5 kHz), subcarrier control signal (center frequency = 3.
5fH = about 55.1kHz), subcarrier facsimile signal (center frequency = 4.5fH = about 70.8kHz)
It is composed of the spectrum of various signals such as. In addition, between and outside the spectrum components of these signals, there are empty spectrum regions which are not currently used. Here, the subcarrier control signal is a signal that is originally used in audio multiplex broadcasting to distinguish between stereo broadcasting and bilingual broadcasting. In the first embodiment, the subcarrier control signal further includes identification A of 100 Hz, for example.
M signals are multiplexed.

When the desired station starts broadcasting, the desired wave is received by the receiving antenna 1, the channel signal is extracted by the input filter 2, the frequency is converted into an IF signal by the receiving section 3, and the first and second signals are obtained by the coupler 4. It is branched and output to the second IF signal. A video IF filter 8 extracts an IF band video signal from the second IF signal, and a level detector 9 detects the video level. The video level is compared with a predetermined threshold level by the first comparison / determination means 10, and the determination result "TV signal is present" is output.

On the other hand, an IF band audio signal is extracted from the second IF signal by the audio IF filter 12, and the IF signal is extracted by the demodulator 13 from the B signal.
Audio is demodulated into a B band audio signal. In this BB band audio signal, a subcarrier control signal is extracted by a subcarrier BB filter 14, and an amplitude component is detected by an AM detector 15. An identification AM signal (in this case, a sine wave signal having a frequency of 100 Hz) is extracted from this amplitude component by the identification signal extraction filter 16. The level of this identification AM signal is the second comparison / determination means 1
In step 7, the threshold value is compared with a predetermined threshold level, and the determination result that "the identification signal is present" is output.

First and second comparison / determination means 10, 17
In response to the determination result from, the transmission unit drive signal for driving the transmission unit 5 is output from the transmission control unit 11a, and the transmission unit 5 is driven. As a result, the first IF signal is transmitted to the transmitter 5
The signal is amplified by and is frequency-converted to the desired wave again and output.
The output filter 6 removes unnecessary spurious from this desired wave, and the signal is transmitted again from the transmitting antenna 7.

On the other hand, when the desired station finishes broadcasting, the desired wave is not received, so that the first and second comparison / determination means 10 and 17 say "no TV signal" and "no identification signal". The determination results are output respectively. Upon receiving this determination result, a transmission unit drive signal for stopping the transmission unit 5 is output from the transmission control unit 11a, and the transmission unit 5 is stopped.

If a jamming station having the same channel as the desired station broadcasts while the desired station is not broadcasting,
Similar to the case of the desired wave, the interfering wave is received by the receiving antenna 1, and then the video level detected from the IF band video signal is compared with a predetermined threshold level by the first comparing and judging means 10 to obtain the video level. Exceeds the threshold level, “T
The determination result "V signal is present" is output.

On the other hand, the subcarrier control signal detected from the IF band audio signal is not AM-modulated, or A
Even if M-modulated, the modulation frequency is different from the modulation frequency of the desired wave, so the identification AM signal is not extracted from the identification signal extraction filter 16, and the second comparison / determination means 17
Outputs a determination result of "no identification signal". As a result, the transmitter drive signal for driving the transmitter 5 is not output from the transmission controller 11a, and the transmitter 5 remains stopped.

In the first embodiment, the subcarrier control signal is AM-modulated at 100 Hz to determine whether it is a desired wave or an interfering wave, but it is not currently used in the spectrum of the audio signal shown in FIG. 9fH = about 141.6k
A similar identification signal may be provided for Hz. Further, the modulation by the identification signal is not limited to the AM modulation.

As described above, in the first embodiment, the identification AM signal is multiplexed with the subcarrier control signal in the audio signal,
Since the desired wave or the interfering wave is discriminated by detecting the identification AM signal, there is an effect that the relay broadcasting device can be prevented from operating with respect to the interfering wave.

Embodiment 2. Next, a second embodiment according to the present invention will be described. In the second embodiment, the relay broadcasting system is composed of a relay broadcasting device on the sending side and a relay broadcasting device on the receiving side corresponding thereto. The relay broadcast device on the sending side is arranged in advance in consideration of the positional relationship between the desired station and the interfering station so as to drive only the desired wave. As a result, only the TV signal from the desired station is received,
The voice carrier signal is modulated with a station code indicating the broadcasting station and retransmitted. On the other hand, the relay broadcasting device on the receiving side identifies the station code, and relays and retransmits only the TV signal retransmitted from the corresponding relay broadcasting device on the sending side.

FIG. 3 is a block diagram of a relay broadcast apparatus on the sending side according to the second embodiment. In the figure, 1-4,
Nos. 6 to 11 and 200 have the same configurations as those of the conventional relay broadcast apparatus shown in FIG. 5a in the figure
Is the same as the configuration of the conventional transmission unit 5 except for the broadcast wave control means 2 described later.
4 is a transmission unit according to the present embodiment to which modulation means (not shown) for ON / OFF control of the voice carrier signal according to No. 4 is added. Reference numeral 100a denotes a relay broadcasting apparatus body according to the present embodiment, which corresponds to the conventional relay broadcasting apparatus body 100.
Reference numeral 18 is a signal branching unit for branching a part of the TV signal from the output filter 6.

Further, 19 is an output detector for detecting the level of the branched TV signal and detecting the start of TV broadcasting depending on the presence or absence of the signal, and 20 is a clock drive for driving a clock generating means 21 described later based on this detection signal. A sending control means for outputting a signal, 21 a clock generating means for generating a clock signal based on the clock driving signal, 22 a station code setting means for setting a station code (3 bits) which is an identification signal for identifying a broadcasting station, 23 is a start bit (1
(Bit) and the station code, a sending signal pulse forming means for generating a notification content signal and outputting the signal at the timing of the clock signal, and 24 ON / OFF-controls and modulates a voice carrier signal based on the notification content signal. It is a broadcast wave control means. Here, the output detector 19 and the sending control means 2
0, the clock generation means 21, the station code setting means 22, the transmission signal pulse construction means 23, and the broadcast wave control means 24 constitute the modulation signal generation means 400.

Next, the operation will be described. As mentioned above,
The relay broadcast device on the sending side is arranged to receive only the desired wave from the desired station. The desired wave received by the receiving antenna 1 is output from the output filter 6 after being processed in the relay broadcast apparatus main body 100a. A part of this desired wave is branched by the signal branching means 18, and the output detector 19 detects the start of TV broadcasting. Based on this detection result, the sending control means 20 generates a clock drive signal and drives the clock generation means 21. The clock generating means 21 generates a clock signal of a predetermined cycle, and the sending signal pulse forming means 23.
Output to. The start signal and the station code indicating the desired station set by the station code setting means 22 are input to the transmission signal pulse forming means 23. Transmission signal pulse forming means 23
Outputs 1 bit of the start bit and 3 bits of the station code as a notification content signal at the timing of the clock signal. The broadcast wave control means 24 controls ON / OFF of the audio carrier wave signal for the transmitter 5a based on the notification content signal. Therefore, the transmitting unit 5a outputs a desired wave in which ON / OFF control is applied to the voice carrier signal, passes through the output filter 6, and is retransmitted from the transmitting antenna 7.

FIG. 4 is an explanatory diagram of ON / OFF control for the voice carrier signal. In this description, the start bit is 1, and the station code is 1, 0, 1; however, the present invention is not limited to this. The voice carrier signal is modulated according to the 1 and 0 bits of the message content signal. Where the modulation index {=
(A−B) / (A + B) × 100 (%)} is arbitrarily set in each relay broadcasting system.

FIG. 5 is a block diagram of a relay broadcast apparatus on the receiving side according to the second embodiment. In the figure, 1-1
Nos. 0, 100, and 200 have the same configurations as those of the conventional relay broadcasting device shown in FIG. 1 in the figure
A transmission control unit 1b outputs a transmission unit drive signal for controlling the drive / stop of the transmission unit 5 based on the determination results from the comparison determination unit 10 and the station code determination unit 26 described later.

Reference numeral 12 is a voice IF filter for extracting an IF band voice signal from the second IF signal, 35 is a report content signal detector for detecting a report content signal from this IF band voice signal,
Reference numeral 21 is a clock generating means for generating a clock signal based on this detection output, 25 is a notification content signal reading means for reading a notification content signal based on this clock signal, and 26 is a station code and a preset value in the read notification content signal. It is a station code discriminating means for comparing with a reference station code which has been set and outputting an identification result. Here, the voice IF filter 12, the notification content signal detector 35, the clock generating means 21, the notification content signal reading means 25, and the station code determining means 26 constitute the identification signal detecting means 310 which is the second input detecting means. ing.

Next, the operation will be described. When the desired station starts broadcasting, the desired broadcast wave is retransmitted with the station code added by the relay broadcast device on the sending side. The desired wave to which the station code is added is received by the receiving antenna 1 of the relay broadcast apparatus on the receiving side, the channel signal is extracted by the input filter 2, the frequency is converted into the IF signal by the receiving unit 3, and the coupler 4 is used. It is branched and output to the first and second IF signals. This second IF signal is processed by the input detection means 200, and finally the image level is compared with a predetermined threshold level by the comparison and determination means 10, and the determination result "TV signal present" is output.

On the other hand, an IF band audio signal is extracted by the audio IF filter 12 from the second IF signal, and the notification content signal is detected by the notification content signal detector 35. A clock signal is generated by the clock generation means 21 based on this detection output, and the notification content signal is read into the notification content signal reading means 25 based on this clock signal. The station code discriminating means 26 compares the station code in the read notification content signal with the reference station code, and outputs a discrimination result of "code coincidence" when the codes match.

Upon receiving the determination / identification results from the comparison / determination means 10 and the station code determination means 26, a transmission section drive signal for driving the transmission section 5 is output from the transmission control section 11b,
The transmitter 5 is driven. As a result, the first IF signal is amplified by the transmission unit 5, frequency-converted into a desired wave again, and output. The output filter 6 removes unnecessary spurious from this desired wave, and the signal is transmitted again from the transmitting antenna 7.

On the other hand, when the desired station finishes broadcasting, the desired wave is not received. Therefore, from the comparison / determination means 10 and the station code determination means 26, "no TV signal",
The determination / identification results of "code mismatch" are output. In response to this result, a transmission unit drive signal for stopping the transmission unit 5 is output from the transmission control unit 11b, and the transmission unit 5
Is stopped.

If a disturbing station having the same channel as the desired station broadcasts when the desired station is not broadcasting,
Similar to the case of the desired wave, the interfering wave is received by the receiving antenna 1 and then the video level detected from the IF band video signal is compared with a predetermined threshold level by the comparison / determination means 10 to threshold the video level. When the value level is exceeded, a determination result "TV signal is present" is output.

On the other hand, in the IF band audio signal, there is no notification content signal, or even if it exists, the station code is different from the reference station code (station code of the desired station), the station code discriminating means 26 The identification result "code mismatch" is output.
As a result, the transmission unit drive signal for driving the transmission unit 5 is not output from the transmission control unit 11b, and the transmission unit 5 remains stopped.

As described above, according to the second embodiment, the voice carrier signal is modulated with the station code, the station code is detected, and compared with the reference station code to discriminate between the desired wave and the interfering wave. Therefore, the relay broadcasting device can be prevented from operating with respect to the interfering wave.

Embodiment 3. Next, a third embodiment according to the present invention will be described. In the third embodiment, two receiving antennas are provided, one of which is oriented so that the desired wave can be received at the maximum level, and the other of which is oriented so that the interfering wave can be received at the maximum level. Then, the levels received by each are compared, and the desired wave / interference wave is discriminated based on the result.

FIG. 6 is a block diagram of a relay broadcast apparatus according to the third embodiment. In the figure, 2 to 10
Nos. 0 and 200 are the same as the configuration of the conventional relay broadcast apparatus shown in FIG. Also 2b, 3b, 8
Since b, 8c, 9b, and 9c are the same as the corresponding parts of the related art, the description thereof will be omitted. In the figure, 1a is a receiving antenna directed to the direction of the desired station, 1b is a receiving antenna directed to the direction of the interfering station, 28 is a level comparing means for comparing the levels of the desired wave and the interfering wave, and 11c is the input detecting means 200.
It is a transmission control unit that outputs a transmission unit drive signal for controlling the drive / stop of the transmission unit 5 based on the determination results of the comparison determination unit 10 and the level comparison unit 28. Here, the input filter 2b, the receiving section 3b, the video IF filters 8b and 8c, the level detectors 9b and 9c, and the level comparing means 28 are the interference wave detecting means 50 which is the second input detecting means.
Configures 0.

Next, the operation will be described. FIG. 7 is an explanatory diagram of the positional relationship between the desired station, the jamming station, and the relay broadcast device according to the third embodiment. When the desired station starts broadcasting, the desired waves are received by the receiving antennas 1a and 1b, respectively, and their levels are detected by the level detectors 9b and 9c. This detection output level is compared by the level comparison means 28. At this time, as described above, the receiving antenna 1a receives the desired wave at the maximum level, so that the output level of 9b is higher than the output level of 9c. Therefore, in such a case, the level comparison means 28 determines that "the desired wave is present" and sends the result to the control section 11c.

Next, the comparison / determination means 10 and the level comparison means 2
In response to the determination result from 8, the transmission unit drive signal for driving the transmission unit 5 is output from the transmission control unit 11c, and the transmission unit 5
Is driven. As a result, the first IF signal is amplified by the transmission unit 5, frequency-converted into a desired wave again, and output. The output filter 6 removes unnecessary spurious from this desired wave, and the signal is transmitted again from the transmitting antenna 7.

On the other hand, when the desired station has finished broadcasting and the interfering station is broadcasting, the interfering wave is the receiving antenna 1a,
1b, and the level is detected by the level detector 9
b, 9c are detected. This detection output level is compared by the level comparison means 28. At this time, as described above, the receiving antenna 1b receives the interfering wave at the maximum level.
Is higher than the output level of 9b. Therefore, in such a case, the level comparison means 28 determines that "interfering wave exists" and sends the result to the control section 11c.

Next, the comparison / determination means 10 and the level comparison means 2
In response to the determination result from 8, the transmission unit drive signal for stopping the transmission unit 5 is output from the transmission control unit 11c, and the transmission unit 5
Is stopped.

As described above, according to the third embodiment, the receiving antenna for directing the desired station and the receiving antenna for the interfering station are separately provided, and the levels received by the respective antennas are compared with each other. Since the distinction between the wave and the disturbing wave is made, there is an effect that the relay broadcasting device can be prevented from operating with respect to the disturbing wave.

Fourth Embodiment Next, a fourth embodiment according to the present invention will be described. In the fourth embodiment, as in the second embodiment, the relay broadcasting system is configured by the relay broadcasting device on the sending side and the relay broadcasting device on the receiving side corresponding to the relay broadcasting device. The relay broadcast device on the sending side is arranged in advance in consideration of the positional relationship between the desired station and the interfering station so as to drive only the desired wave. As a result, only the TV signal from the desired station is received, and the desired wave is retransmitted to the relay broadcast device on the receiving side. On the other hand, the receiving-side relay broadcasting device is provided with two receiving antennas, one of which is directed toward the desired station and the other of which is directed toward the sending-side relay broadcasting device. Then, the levels received by each are compared, and the desired wave / interference wave is discriminated based on the result.

FIG. 8 is a block diagram of a relay broadcast apparatus on the receiving side according to the fourth embodiment. In the figure, 2-7,
Since 100 and 200 have the same configuration as that of the conventional relay broadcast apparatus shown in FIG. 13, description thereof will be omitted. Also 2c, 3c,
Since 8d, 9d, and 10b are the same as the corresponding parts in the related art, description thereof is omitted. In the figure, reference numeral 1c designates a direction of a desired station, and a receiving antenna 1d for receiving a desired wave (hereinafter, referred to as "direct desired wave") directly transmitted from the desired station, 1d points a direction of a relay broadcasting device on a sending side. , A receiving antenna for receiving a desired wave (hereinafter, referred to as “indirect desired wave”) indirectly transmitted from a desired station via the relay broadcast device on the sending side. Here, the input filter 2c, the receiving unit 3c, and the video I
F filter 8d, level detector 9d, comparison and determination means 10
b is a desired wave detecting means 600 which is a second input detecting means.
Are configured. Reference numeral 11d outputs a transmitter drive signal for controlling the drive / stop of the transmitter based on the determination results by the comparison and determination means 10 in the input detection means 100 and the comparison and determination means 10b in the desired wave detection means 600. It is a transmission control unit.

Next, the operation of the relay broadcast apparatus will be described with reference to FIGS. FIG. 9 is an explanatory diagram of the positional relationship between the desired station, the interfering station, and the relay broadcast device according to this embodiment.

When the desired station starts broadcasting, the desired wave is directly received by the receiving antenna 1c of the relay broadcasting apparatus on the receiving side,
The indirect desired wave is received by the receiving antenna 1d of the relay broadcasting device on the receiving side via the relay broadcasting device on the transmitting side. Next, the video level of the desired wave is directly detected by the level detector 9, and this video level is compared with a predetermined threshold level by the comparison / determination means 10, and the determination result "TV signal present" is output. On the other hand, the image level of the indirect desired wave is detected by the level detector 9d, and this image level is compared and determined by the comparing / determining means 10b.
Is compared with a predetermined threshold level, and "with TV signal"
Is output. In the transmission control unit 11d,
Upon receiving the determination result of "TV signal present" from the comparison determination means 10 and 10b, a transmission unit drive signal for driving the transmission unit 5 is output, and the transmission unit 5 is driven. As a result, the desired wave is directly amplified by the transmitter 5 and is again transmitted from the transmitting antenna 7.

On the other hand, when the desired station finishes broadcasting, directly
Since neither of the indirect desired waves is received by the relay broadcast device on the receiving side, the comparison / determination means 10 and 10b output the determination result "no TV signal". Upon receiving this determination result, the transmission control signal for stopping the transmission unit 5 is output from the transmission control unit 11d, and the transmission unit 5 is stopped.

If a disturbing station having the same channel as the desired station broadcasts while the desired station is not broadcasting,
Similar to the case of the desired wave, the interfering wave is directly received by the receiving antenna 1c, and thereafter, the video level detected from the IF band video signal is compared with a predetermined threshold level by the comparison and determination means 10 to check the video level. When the threshold level is exceeded, "T
The determination result "V signal is present" is output.

On the other hand, since the receiving antenna 1d does not point to the interfering station, the image level detected by the level detector 9d does not reach the predetermined threshold value, and the level comparing means 10b indicates "no TV signal". The judgment result is output. As a result, the transmission unit drive signal for driving the transmission unit 5 is not output from the transmission control unit 11d, and the transmission unit 5 remains stopped.

As described above, in the fourth embodiment, the relay broadcast device on the sending side that receives only the desired wave and retransmits it as the indirect desired wave is provided, and the indirect desired wave is received on the relay broadcast device on the receiving side. Since the interference wave is distinguished by the presence or absence of
There is an effect that the relay broadcast device can be prevented from operating with respect to the interfering wave.

Embodiment 5. Next, a fifth embodiment of the invention will be described. In the fifth embodiment, the configuration of the relay broadcast apparatus on the sending side in the second embodiment is different from the relay broadcast apparatus internal state (for example, “power failure”, “cooling fan abnormality”, “temperature abnormality”, etc. of the relay broadcast apparatus). Added monitoring function.
In addition, a function was provided to output and display this monitored state.

FIG. 10 is a block diagram of a relay broadcast apparatus according to the fifth embodiment. In the figure, 1-4, 5a,
6 to 11, 18, 100a, 200, 19 to 21 are shown in FIG.
Since the configuration is the same as that of the relay broadcast device on the sending side of the second embodiment shown in FIG. Also, 22a to 24a, 4
Since 00a also corresponds to 22 to 24 and 400 in FIG. 3, description thereof will be omitted. In the figure, reference numeral 33 is a monitoring item input means for outputting a monitoring code (3 bits) which is a monitoring item signal corresponding to each state from the result of each monitoring item of the state in the relay broadcasting apparatus.

Next, the operation will be described. The desired wave received by the receiving antenna 1 is output from the output filter 6 after being processed in the relay broadcast apparatus main body 100a. A part of this desired wave is branched by the signal branching means 18, and the output detector 19 detects the start of TV broadcasting. Based on this detection result, the sending control means 20 generates a clock drive signal and drives the clock generation means 21. Clock generation means 21
Generates a clock signal of a predetermined cycle and outputs it to the sending signal pulse forming means 23a. The operating condition (normal / abnormal) corresponding to the monitoring item in the relay broadcasting device is input to the monitoring item input means 33 and output as a monitoring code.
A start bit, a station code indicating a desired station set by the station code setting means 22, and the monitoring code are input to the transmission signal pulse forming means 23a. The sending signal pulse composing means 23a outputs the start bit 1 bit, the station code 3 bits and the monitor code bit as a notification content signal at the timing of the clock signal. The broadcast wave control means 24a performs ON / OFF control of the audio carrier wave signal for the transmission section 5a based on this notification content signal. Therefore, the transmitting unit 5a outputs a desired wave in which ON / OFF control is applied to the voice carrier signal, passes through the output filter 6, and is retransmitted from the transmitting antenna 7.

FIG. 11 shows ON / OFF for the voice carrier signal.
It is an explanatory view of control. In this description, the start bit is 1, the station code is 1, 0, 1 and the monitoring code is 1, 1,
However, it is not limited to this. The voice carrier signal is modulated according to the 1 and 0 bits of the message content signal.

FIG. 12 is a block diagram of a TV receiver which is a broadcast receiving apparatus according to the fifth embodiment. In the figure, reference numerals 1, 12, 21, 25a, 26, 35 and 310a have the same or corresponding configurations as those of the second embodiment shown in FIG. In the figure, 34 is a TV receiver main body which is a main body of a broadcast receiving apparatus which is commercially available, and 27
Is a notification signal control means for outputting the status of the relay broadcasting device corresponding to the monitoring item from the monitoring code from the notification content signal reading means 25a, 36 is a notification signal display means for displaying the status of the relay broadcasting device, and 37 is a relay broadcasting device. It is a buzzer control means for controlling the buzzer 38 based on the state. Here, the notification signal control means 27, the notification signal display means 36, the buzzer control means 37, and the buzzer 38 are the monitoring item output means 7
00 is configured.

Next, the operation will be described. When the desired station starts broadcasting, the desired wave is retransmitted with the station code and the monitoring code added by the relay broadcasting device. The desired wave to which the station code and the supervisory code are added is received by the receiving antenna 1 of the TV receiver, the channel signal is extracted by the TV receiver main body 34, and then frequency-converted into an IF signal for output. The IF signal is extracted from the IF signal by the audio IF filter 12, and the notification content signal detector 35 detects the notification content signal. A clock signal is generated from the clock generating means 21 based on this detection output, and the notification signal content is read into the notification signal content reading means 25a based on this clock signal. In the station code discriminating means 26, the station code in the read notification content signal is compared with the reference station code, and if the codes coincide, the discrimination result "code coincidence" is output as a control signal.

On the other hand, a monitoring code is input to the notification signal control means 27, and the monitoring code is output as a status signal based on the result of the "code coincidence" judgment by the station code judging means 26. This status signal is the notification signal display means 36.
Displays the monitoring result. Alternatively, the buzzer control means 37 is driven to drive the buzzer 38.

On the other hand, when the desired station finishes broadcasting, the desired wave is not received, so that the station code discriminating means 26 outputs an identification result of "code mismatch". As a result, the notification signal control means 27 is stopped.

If a disturbing station having the same channel as the desired station broadcasts while the desired station is not broadcasting,
Although the interfering wave is received by the receiving antenna 1 as in the case of the desired wave, the IF band audio signal has no notification content signal, or even if it exists, the station code is the reference station code (the station of the desired station). Station code discriminating means 26
Outputs an identification result of "code mismatch". As a result, the notification signal control means 27 remains stopped.

As described above, in the fifth embodiment, the voice carrier signal is modulated with the station code and the supervisory code,
By detecting the station code and comparing it with the reference station code, it is possible to distinguish between the desired wave and the interfering wave.
Only when the desired wave is received, there is an effect that the TV receiver can output the monitoring state of the relay broadcasting device corresponding to the monitoring code.

[0068]

As described above, according to the present invention, the desired signal or the disturbing wave can be discriminated by detecting the identification signal such as the identification AM signal or the station code from the voice signal. There is an effect that the relay broadcast device can be prevented from operating with respect to the interfering wave.

In the relay broadcasting device on the sending side, the voice carrier signal is modulated by the station code which is the identification signal indicating the desired wave so that the desired wave or the interfering wave can be discriminated. There is an effect that the relay broadcasting device on the receiving side can be prevented from operating with respect to the interfering wave.

Further, a receiving antenna pointing to the desired station and a receiving antenna pointing to the interfering station are separately provided and the levels received by the respective antennas are compared to distinguish between the desired wave and the interfering wave. Therefore, there is an effect that the relay broadcast device can be prevented from operating with respect to the interfering wave.

Further, since the direct desired wave from the desired station and the indirect desired wave from the relay broadcasting device on the sending side are received, and the interfering wave is discriminated by whether or not the indirect desired wave is received, the interfering wave is detected. However, the relay broadcasting device on the receiving side can be prevented from operating.

Further, since the information indicating the operating state in the relay broadcasting apparatus is added by modulating the sound carrier signal with the monitoring code, the broadcasting receiving apparatus can monitor the operating state of the relay broadcasting apparatus. .

[0073]

[Brief description of drawings]

FIG. 1 is a block diagram of a relay broadcast device according to a first embodiment of the present invention.

FIG. 2 is a BB of an audio signal in a TV signal for explaining the operation of the relay broadcast device according to the first embodiment of the present invention.
It is explanatory drawing of the spectrum in a zone.

FIG. 3 is a block diagram of a relay broadcast device on a sending side according to a second embodiment of the present invention.

FIG. 4 is an ON / O to audio carrier signal for explaining the operation of the relay broadcast apparatus according to the second embodiment of the present invention.
It is explanatory drawing of FF control.

FIG. 5 is a block diagram of a relay broadcast device on the receiving side according to the second embodiment of the present invention.

FIG. 6 is a block diagram of a relay broadcast device according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram of a positional relationship between a broadcasting station and a relay broadcasting device for explaining the operation of the relay broadcasting device according to the third embodiment of the present invention.

FIG. 8 is a block diagram of a relay broadcast device according to a fourth embodiment of the present invention.

FIG. 9 is an explanatory diagram of a positional relationship between a broadcasting station and a relay broadcasting device for explaining an operation of the relay broadcasting device according to the fourth embodiment of the present invention.

FIG. 10 is a block diagram of a relay broadcast device according to a fifth embodiment of the present invention.

FIG. 11 shows ON / OFF of an audio carrier signal for explaining the operation of the relay broadcast apparatus according to Embodiment 5 of the present invention.
It is explanatory drawing of OFF control.

FIG. 12 is a block diagram of a broadcast receiving device according to a fifth embodiment of the present invention.

FIG. 13 is a block diagram of a conventional relay broadcasting device.

FIG. 14 is an explanatory diagram of a positional relationship between a broadcasting station and a relay broadcasting device for explaining the operation of a conventional relay broadcasting device.

FIG. 15 is an explanatory diagram of input / output levels of the relay broadcasting device for explaining the operation of the conventional relay broadcasting device.

[Explanation of symbols]

1 receiving antenna 1a receiving antenna 1b receiving antenna 3 Receiver 3b receiver 3c receiver 5 transmitter 5a transmitter 11 Transmission control unit 11a Transmission control unit 11b Transmission control unit 11c Transmission control unit 11d transmission control unit 34 TV receiver body 200 Input detection means 300 identification signal detecting means 310 Identification signal detecting means 310a Identification signal detecting means 400 Modulation signal generation means 400a Modulation signal generation means 500 Interfering wave detection means 600 Desired wave detection means 700 Monitoring item output means

Claims (4)

(57) [Claims] 1. A receiver for receiving a radio signal from a broadcasting station and outputting an intermediate frequency signal, and modulating the intermediate frequency signal with a modulation signal,
A transmitter that amplifies and outputs as a radio signal, and detects a video signal from the intermediate frequency signal, and when the level of this video signal exceeds a predetermined level that is not a signal, a TV
An input detecting means for outputting a transmitter control signal indicating that there is a signal, and driving the transmitter when receiving the transmitter control signal,
A transmission control unit that outputs the wireless signal, and a wireless signal output from the transmission unit are detected, and the detection is performed.
A relay broadcast apparatus comprising: a modulation signal generating unit that generates the modulation signal that is a notification content signal including an identification signal that indicates a radio signal from the broadcasting station based on the result . 2. A first receiving antenna that receives a wireless signal from a first broadcasting station, a second receiving antenna that receives a wireless signal from a second broadcasting station, and the first receiving antenna. A receiver that receives the received wireless signal and outputs an intermediate frequency signal, a transmitter that amplifies the intermediate frequency signal and outputs it as a wireless signal, and detects a video signal from the intermediate frequency signal, and the level of the video signal When the TV exceeds a predetermined level that is not a signal, TV
First input detection means for outputting a first transmission unit control signal indicating that there is a signal, the level of the radio signal received by the first receiving antenna, and the radio received by the second receiving antenna Second input detection means for comparing a signal level with each other and outputting a second transmitter control signal when the radio signal received by the first receiving antenna is larger; A relay broadcast apparatus comprising: a transmission control unit that drives the transmission unit when a transmission unit control signal is output together and outputs a radio signal received by the first receiving antenna. 3. A first receiving antenna for directly receiving a wireless signal from a first broadcasting station, and a first receiving antenna for indirectly receiving a wireless signal from the first broadcasting station via another relay broadcasting device. A second receiving antenna; a receiving unit that receives the wireless signal received by the first receiving antenna and outputs an intermediate frequency signal; a transmitting unit that amplifies the intermediate frequency signal and outputs the intermediate frequency signal; The video signal is detected from the signal, and when the level of this video signal exceeds a predetermined level that is not no signal, the TV
A first input detecting means for outputting a first transmitter control signal indicating that there is a signal; and a video signal detected from the radio signal received by the second receiving antenna, and the level of the video signal is not detected. Second, which indicates that there is a TV signal when the level exceeds a predetermined level which is not a signal
Second input detection means for outputting a transmitter control signal of the above, and when the first and second transmitter control signals are both output, the transmitter is driven and received by the first receiving antenna. A relay broadcast apparatus comprising: a transmission control unit that outputs a radio signal. 4. A receiver for receiving a radio signal from a broadcasting station and outputting an intermediate frequency signal, and modulating the intermediate frequency signal with a modulation signal,
A transmitter which amplifies and outputs as a radio signal, and a video signal is detected from the intermediate frequency signal, and a transmitter control signal indicating that a TV signal is present is output when the level of the video signal exceeds a predetermined level that is no signal. Input detecting means for driving the transmitter when receiving the transmitter control signal,
A transmission control unit that outputs the wireless signal, and a wireless signal output from the transmission unit are detected, and the detection is performed.
Modulation signal generating means for generating the modulation signal, which is a notification content signal including an identification signal indicating a radio signal from the broadcasting station and a monitoring item signal indicating a monitoring state in the relay broadcasting device based on the result. A relay broadcasting device characterized in that