JP5052325B2 - Relay broadcast station equipment - Google Patents

Description

  The present invention relates to a relay broadcast station device for relaying broadcast radio waves to difficult viewing areas such as mountainous areas in a TV broadcast system, and more particularly, to an MCPA (Multi Channel Power Amplifier) relay broadcast station device.

  2. Description of the Related Art Conventionally, in a broadcast system for TV broadcasting, a relay broadcast station apparatus is used to transmit broadcast radio waves to difficult viewing areas such as mountainous areas. This relay broadcast station device is installed inside a relay station built near the top of a mountain, for example, and receives radio waves transmitted from the broadcast station with an antenna, where it amplifies signals and removes noise. Then, the transmission signal is formed again and transmitted to the target difficult viewing area.

  In a general relay broadcast station device, broadcast radio waves are demultiplexed into signals for each channel at the front end, and converted into signals of intermediate frequency bands (intermediate signals), respectively. Remove and amplify necessary signals. The intermediate signal that has been subjected to noise removal or the like is sent to the excitation unit, where it is converted again to a predetermined transmission frequency, synthesized by an output mixer, and transmitted.

  Such a relay broadcasting station apparatus is roughly classified into an MCPA system and an SCPA system (Single Channel Power Amplifier) according to an amplification system. MCPA system is a system that amplifies multiple channels at once without demultiplexing, and can construct broadcasting equipment for multiple channels in a space-saving and low-cost manner. It is suitable for relay stations that are not separated (see, for example, Patent Document 1). On the other hand, the SCPA method is a method in which a plurality of channels are demultiplexed for each channel and individually amplified, and is suitable for a high-power relay station.

  FIG. 4 is a block diagram of a conventional MCPA relay broadcast station apparatus. The relay broadcast station apparatus 100 includes a receiving antenna 101, a duplexer 102, a plurality of transmission / reception converters 103, a combiner 104, a distributor 105, a plurality of (here, two) amplifiers (MCPA) 106, and a switching unit. 107, an output filter 108, a transmission antenna 109, and a multi-channel wattmeter (MCPA wattmeter) 110. Each reception / transmission conversion unit 103 includes a reception conversion unit 103a, a transmission conversion unit 103b, and a switching unit 103c. In such a configuration, the broadcast radio wave received by the receiving antenna 101 is demultiplexed into a signal for each channel by the demultiplexer 102 and input to the transmission / reception conversion unit 103 corresponding to each channel. In the reception / transmission conversion unit 103, the reception conversion unit 103a performs gain adjustment and frequency conversion to an intermediate frequency on the input signal to generate an intermediate signal, and outputs the intermediate signal to the transmission conversion unit 103b. The transmission conversion unit 103b performs processing such as gain adjustment, frequency conversion, and noise removal on the intermediate signal, and generates and outputs an output signal. This output signal is synthesized by the synthesizer 104, then distributed to two systems by the distributor 105, and after a plurality of channels are collectively amplified in each amplifying unit 106, An output signal is output from the transmission antenna 109 via the switching unit 107 and the output filter 108.

  FIG. 5 is a block diagram of a conventional SCPA relay broadcast station apparatus. The relay broadcast station device 120 includes a reception antenna 121, a plurality of distributors 122 configured in multiple stages, a plurality of reception / transmission conversion units 123, a combiner 124, an output filter 125, and a transmission antenna 126. . Each reception / transmission conversion unit 123 includes a reception conversion unit 123a, a transmission conversion unit 123b, an amplification unit (SCPA) 123c, and a switching unit 123d. In such a configuration, the broadcast radio wave received by the receiving antenna 121 is distributed to each channel by the distributor 122 and then input to the transmission / reception conversion unit 123. In the reception / transmission conversion unit 123, the reception conversion unit 123a performs gain adjustment and frequency conversion to an intermediate frequency on the input signal to generate an intermediate signal, and outputs the intermediate signal to the transmission conversion unit 123b. The transmission conversion unit 123b performs processing such as gain adjustment, frequency conversion, and noise removal on the intermediate signal to generate and output an output signal. This output signal is amplified for each channel by the amplifying unit 123c, synthesized by the synthesizer 124, and then output from the transmission antenna 126 via the output filter 125.

Japanese Patent Laid-Open No. 2002-077066

  Here, in the relay broadcasting station apparatus 120 of the SCPA system as shown in FIG. 5, by providing AGC (Automatic Gain Control) in the amplifying unit 123c for each channel and appropriately setting the amplification factor (gain), for example, Even when the input level of each channel varies, it is possible to control the variation of the output level for each channel and suppress the variation of the output level of each channel to about ± 10%, for example. Further, since the fluctuation of the output level can be controlled in this way, when the fluctuation of the output level becomes large, it can be determined that some abnormality has occurred in the relay broadcast station apparatus 120, and the relay broadcast station apparatus 120 abnormalities can be easily detected.

  However, in the MCPA relay broadcast station apparatus 100 as shown in FIG. 4, since the amplifying unit 106 amplifies a plurality of channels at once, simple AGC cannot be performed. In other words, the reason why the output level of each channel fluctuates is not only when the input level of each channel fluctuates, but also when the number of channels itself fluctuates, such as when only some channels are suspended. Because such variation factors cannot be specified by AGC, if the input signal is amplified with a uniform amplification factor regardless of the variation factors, it is not possible to appropriately control variations in the output level of each channel. . Further, since the fluctuation of the output level cannot be suppressed in this way, even if the fluctuation of the output level becomes large, it cannot be determined whether or not any abnormality has occurred in the relay broadcast station device 100. It is difficult to detect an abnormality in the relay broadcast station device 100.

  Conventionally, in view of the problems in the MCPA relay broadcasting station apparatus 100, as shown in FIG. 4, a multichannel wattmeter 110 for measuring and monitoring the RF level for each channel is provided, and this multichannel power is provided. Based on the RF level measured by the total 110, the fluctuation of the output level is controlled and the abnormality of the relay broadcast station apparatus 100 is detected. When an abnormality is detected, an abnormality signal is output from the multichannel wattmeter 110 to the remote monitoring station. However, this multi-channel wattmeter 110 is relatively expensive, which has been a cause of increasing the installation cost of the relay broadcast station apparatus 100.

  The present invention has been made in view of the above, and an MCPA relay broadcast station apparatus capable of performing output level fluctuation control and relay broadcast station apparatus abnormality detection without using a multichannel wattmeter. The purpose is to provide.

In order to solve the above-described problems and achieve the object, the relay broadcast station apparatus according to claim 1 includes a plurality of reception conversion means for receiving and converting a signal of a plurality of channels for each channel, and a signal subjected to reception conversion. and a plurality of transmission converting means for transmitting converted for each channel, the relay broadcasting station apparatus and a amplifying means for collectively amplifying signals of a plurality of channels that are transmitted converted, to the level of the signal in the preceding stage of the amplifier means detecting the number of the channel on the basis, on the basis of the level of the output signal from said amplifying means to determine the number of the channel, depending on the number of the detected the channel, the number of the calculated by channel Channel monitoring control means for controlling the relay broadcast station apparatus .

The relay broadcast station apparatus according to claim 2 is the relay broadcast station apparatus according to claim 1, wherein the channel monitoring control means detects the channel detected based on a signal level in a preceding stage of the amplification means. The total output level calculated by multiplying the number of each by a predetermined individual output level for each channel is set as the output level of the amplifying means, and the level of the output signal from the amplifying means is set for each channel. The number of channels is calculated by dividing by a predetermined individual output level, and based on the number of channels detected based on the signal level in the previous stage of the amplification means and the level of the output signal from the amplification means The broadcast status for each channel is determined according to the calculated number of channels, and according to the determined broadcast status. Controlling the relay broadcasting station apparatus, and wherein.

The relay broadcast station apparatus according to claim 3 is the relay broadcast station apparatus according to claim 1 or 2, wherein the channel monitoring control means is based on a level of an input signal to each of the plurality of reception conversion means. And detecting the number of the channels .

Also, the relay broadcast station apparatus according to claim 4 is the relay broadcast station apparatus according to any one of claims 1 to 3, wherein the channel monitoring control means is an input to each of the plurality of reception conversion means. An abnormality in the reception conversion unit and the transmission conversion unit is detected based on a signal level and an output signal level from each of the plurality of transmission conversion units .

A relay broadcast station apparatus according to claim 5 is the relay broadcast station apparatus according to any one of claims 1 to 4, wherein the relay broadcast station apparatus includes a plurality of the amplifying units and switches the plurality of amplifying units to each other. Switching means for detecting the abnormality of the amplifying means based on the detected number of the channels and the level of the output signal from the amplifying means, and the abnormality is detected. In this case, the amplification means are switched to each other via the switching means .

The relay broadcast station apparatus according to claim 6 is the relay broadcast station apparatus according to claim 5 , wherein the channel monitoring control unit is configured to determine a signal level in the amplification unit based on the number of the detected channels. The control range is calculated, and when the level of the output signal from the amplification means exceeds the calculated control range, the amplification means is determined to be abnormal .

  According to the first aspect of the present invention, the number of channels is detected, and the amplification factor in the amplifying unit is controlled according to the detected number of channels, so that a multi-channel wattmeter is not used. Amplification control during amplification can be performed appropriately.

According to the second aspect of the present invention, the total output level calculated by multiplying the number of detected channels by a predetermined individual output level for each channel is set as the output level of the amplification means. Thus, it is possible to absorb the fluctuation of the appropriate control level accompanying the increase / decrease in the number of channels and appropriately perform the amplification control at the time of collective amplification.
Further, the number of channels is calculated by dividing the level of the output signal from the amplification means by a predetermined individual output level for each channel, and based on the calculated number of channels and the signal level in the previous stage of the amplification means. By determining the broadcast status for each channel based on the number of detected channels, the broadcast state (relay state) in the relay broadcast station device can be notified in detail to a remote monitoring station or the like.

According to the third aspect of the present invention, the number of channels can be detected easily and accurately by detecting the number of channels based on the level of the input signal to each of the plurality of reception conversion means.

According to the fourth aspect of the present invention, based on the level of the input signal to each of the plurality of reception conversion means and the level of the output signal from each of the plurality of transmission conversion means, the reception conversion means and the transmission conversion By detecting the abnormality of the means, the reception conversion means and the transmission conversion means can be switched from the active system to the standby system, or notified to an abnormal remote monitoring station or the like, and the reliability of broadcast relay can be improved.

According to the present invention as set forth in claim 5, the abnormality of the amplification means is detected based on the number of detected channels and the level of the output signal from the amplification means, and the switching means is detected when the abnormality is detected. Since the amplifying means are switched to each other through the broadcasting, it is possible to continue broadcasting even when an abnormality occurs in the amplifying unit, and to improve the reliability of broadcast relay.

According to the present invention as set forth in claim 6, the control range of the signal level in the amplification means is calculated based on the number of detected channels, and the level of the output signal from the amplification means exceeds the calculated control range. In this case, by determining that the amplification means is abnormal, it is possible to absorb fluctuations in the appropriate control range that accompany the increase or decrease in the number of channels and perform abnormality detection appropriately.

  Exemplary embodiments of a relay broadcast station apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings. [I] First, the basic concept of the present embodiment will be described, then [II] the specific contents of the present embodiment will be described, and [III] Finally, a modification to the present embodiment will be described. However, the present invention is not limited by the present embodiment.

[I] Basic concept of the present embodiment First, the basic concept of the present embodiment will be described. The installation purpose of the relay broadcast station apparatus and the type of the relay signal according to the present embodiment are arbitrary, and the radio communication system is a relay station for broadcast radio wave relay in a television broadcast system or broadcast signal relay in a cable broadcast system. It does not matter whether it is a relay station for relaying communication radio waves. Here, the relay broadcast station apparatus according to the present embodiment is an MCPA relay broadcast station apparatus, and amplifies and outputs signals of a plurality of channels that have undergone reception conversion and transmission conversion.

  One of the features of the relay broadcast station apparatus according to the present embodiment is that the number of channels input to the relay broadcast station apparatus is roughly detected, and batch amplification is performed according to the detected number of channels. There is to control the amplification factor for. In this case, even if the output level of each channel fluctuates, it can be determined whether this fluctuation is caused by the fluctuation of the input level of each channel or the number of channels itself. It becomes possible to appropriately control the fluctuation of the output level of the channel. Moreover, since such control can be performed without using a multichannel wattmeter, the installation cost of the relay broadcast station apparatus can be reduced.

[II] Specific contents of the present embodiment Next, specific contents of the present embodiment will be described.

(Configuration of relay broadcasting station equipment)
First, the configuration of the relay broadcast station apparatus according to the present embodiment will be described. FIG. 1 is a block diagram showing a configuration of a relay broadcast station apparatus according to the present embodiment. The relay broadcast station apparatus 1 includes a reception antenna 2, a duplexer 3, a plurality of transmission / reception converters 4, a combiner 5, a distributor 6, a plurality (two in this case) of amplifiers (MCPA) 7, and a switching unit. 8, an output filter 9, and a transmission antenna 10. Each reception / transmission conversion unit 4 includes a reception conversion unit 4a, a transmission conversion unit 4b, and a switching unit 4c.

  In such a configuration, the broadcast radio wave received by the receiving antenna 2 is demultiplexed into a signal for each channel by the demultiplexer 3 and input to the transmission / reception conversion unit 4 corresponding to each channel. In the reception / transmission conversion unit 4, the reception conversion unit 4a performs gain adjustment and frequency conversion to an intermediate frequency on the input signal to generate an intermediate signal, and outputs the intermediate signal to the transmission conversion unit 4b. The transmission conversion unit 4b performs processing such as gain adjustment, frequency conversion, and noise removal on the intermediate signal to generate and output an output signal. This output signal is synthesized by the synthesizer 5, then divided into two systems by the distributor 6, and after a plurality of channels are amplified together in each amplifying unit 7, An output signal is output from the transmission antenna 10 via the switching unit 8 and the output filter 9. The reception conversion unit 4a, the transmission conversion unit 4b, and the amplification unit 7 correspond to the reception conversion unit, the transmission conversion unit, and the amplification unit in the claims, respectively.

  Here, the amplification unit 7 includes an AGC amplifier and a detector (not shown). The AGC amplifier is an automatic gain control amplifier, and adjusts the feedback gain so that the level of the input signal falls within a predetermined reference value. Specifically, the signal after the AGC amplifier is detected by a detector, and the gain is adjusted by feeding back this signal to the AGC amplifier.

  The amplifying unit 7 configured as described above is made redundant. When an abnormality occurs in one amplifying unit 7, the amplifying unit 7 is switched to the other amplifying unit 7 by the switching unit 8. The switching unit 8 corresponds to switching means in the claims. In the following description, the amplifying unit 7 on the used side is referred to as “the amplifying unit 7 on the active side” and the amplifying unit 7 on the unused side (standby side) is referred to as “the amplifying unit 7 on the standby side” as necessary. Called. However, when it is not necessary to distinguish the two, they are simply referred to as “amplifying unit 7”. The reception conversion unit 4a and the transmission conversion unit 4b may be made redundant so that the active side is switched to the standby side when an abnormality occurs.

  Further, the relay broadcast station apparatus 1 according to the present embodiment is provided with a channel monitoring control unit 20. This channel monitoring control unit 20 detects the number of channels based on the signal level in the previous stage of the amplification unit 7 and controls the amplification factor in the amplification unit 7, and corresponds to the channel monitoring control means in the claims. . For example, the channel monitoring control unit 20 includes a CPU (Central Processing Unit), a control program such as an OS (Operating System), a program defining various processing procedures, and necessary data and a control table shown in FIG. And an internal memory for storing. As shown in the figure, the channel monitoring control unit 20 includes a front stage (signal input position) of each reception conversion section 4a, a rear stage (signal output position) of each transmission conversion section 4b, an AGC amplifier of the amplification section 7, and an amplification section 7. The second stage (signal output position) and the switching unit 8 are electrically connected.

(Control of channel monitoring controller 20)
Next, the control of the channel monitoring controller 20 will be described. FIG. 2 is a flowchart of control of the channel monitoring controller 20, and FIG. 3 is a control table used for control of the channel monitoring controller 20. The channel monitoring control unit 20 monitors the signal level at the signal input position of each reception conversion unit 4a (step SA-1) and also monitors the signal level at the signal output position of each transmission conversion unit 4b (step SA-2). ), Whether or not there is an abnormality in the reception conversion unit 4a or the transmission conversion unit 4b is detected. Specifically, the signal level of the transmission conversion unit 4b corresponding to the reception conversion unit 4a is equal to or lower than the predetermined threshold value although the signal level of each reception conversion unit 4a is equal to or higher than the predetermined threshold value (step SA-1, Yes). If there is only one (step SA-2, No), it is determined that one or both of the reception conversion unit 4a and the transmission conversion unit 4b are abnormal, and abnormality control is performed (step SA-3). As the abnormality control, for example, the channel monitoring control unit 20 notifies the occurrence of abnormality by outputting an abnormality signal to a predetermined reporting destination such as a remote monitoring center. Alternatively, when the reception conversion unit 4a and the transmission conversion unit 4b are made redundant, the channel monitoring control unit 20 controls the switching unit 8 for switching between the reception conversion unit 4a and the transmission conversion unit 4b as abnormality control. Thus, the reception conversion unit 4a and transmission conversion unit 4b on the active side are switched to the standby system.

(Control of channel monitoring controller 20-detection of the number of input channels)
Further, the channel monitoring control unit 20 determines the presence / absence of signal input to each reception conversion unit 4a based on the signal level at the signal input position of each reception conversion unit 4a, and based on the determination result, the relay broadcast station apparatus The number of channels input to 1 is detected (step SA-4). For example, when the signal level at the signal input position of any one of the reception conversion units 4a is compared with a predetermined threshold (zero or a plus value considering the noise level), and the signal level exceeds the predetermined threshold, It is determined that there is a signal input for the channel assigned to the reception conversion unit 4a, and the number of channels is incremented by one. Similarly, all the reception conversion units 4a are determined, and the total number of channels is detected. Hereinafter, the total number of channels detected based on the signal input to each reception conversion unit 4a in this way is referred to as “total number of reception determination channels”.

(Control of channel monitoring control unit 20-gain control)
Thereafter, the channel monitoring controller 20 controls the amplification factor in the AGC amplifier of the amplifier 7 according to the total number of reception determination channels. Specifically, the total output level is calculated by multiplying the total number of reception determination channels by a predetermined individual output level for each channel (step SA-5), and this total output level is set as the output level of the AGC amplifier. Set (step SA-6). For example, when the individual output level is 0.3 w, when the total number of reception determination channels is 4, the total output level is 1.2 (= 0.3 × 4) w, and the total number of reception determination channels is 3. If the total output level is 0.9 (= 0.3 × 3) w and the total number of reception determination channels is 2, the total output level is 0.6 (= 0.3 × 2) w and the reception determination channel total When the number is 1, the total output level is set to 0.3 (= 0.3 × 1) w.

  As a result, the AGC amplifier of the amplifying unit 7 performs gain control so as to achieve a total output level corresponding to the total number of reception determination channels. For example, when the total number of reception determination channels is 4, control is performed so that the output level becomes 1.2 w, and when the total number of reception determination channels decreases to 1, the output level becomes 0.3 w. Control is performed. In this case, even if only some of the channels are suspended, the output level of the suspended channels is reduced and the output level of the AGC amplifier is set. The output level can be appropriately controlled.

(Control of channel monitoring controller 20-status determination for each channel)
Next, the channel monitoring control unit 20 determines the status for each channel based on the signal level at the signal output position of the amplification unit 7 and the total number of reception determination channels detected in step SA-4. The result is output to a predetermined report destination such as a remote monitoring center. Specifically, since the amplification factor control in step SA-6 is performed, assuming that the individual output level for each channel is 0.3 w, the total number of reception determination channels is 4, 3, 2, 1. Are predicted to be 1.2 w, 0.9 w, 0.6 w, and 0.3 w at the signal output position of the amplifying unit 7, respectively.

  From this, the number of channels being broadcast can be calculated by dividing the signal level at the signal output position of the amplifier 7 by the individual output level for each channel (in this way, based on the output level of the amplifier 7). The number of channels calculated in this manner is referred to as “amplification determination channel total number”) (step SA-7). For example, when the signal level at the signal output position of the amplification unit 7 is 1.2 w, the total number of amplification determination channels is 4 (= 1.2 / 0.3), and when the signal level is 0.9 w, amplification determination When the total number of channels is 3 (= 0.9 / 0.3) and the signal level is 0.6 w, the total number of amplification determination channels is 2 (= 0.6 / 0.3) and the signal level is 0.3 w. In this case, the total number of amplification determination channels is 1 (= 0.3 / 0.3).

Then, the status for each channel is determined based on the total number of amplification determination channels and the total number of reception determination channels detected in step SA-4 (step SA-8). This combination is shown in the lower part of FIG. Here, the “status” is “broadcasting (when a normal level broadcast signal is input to the reception conversion unit 4a and a signal is output from the amplification unit 7)”, “inactive (broadcast station is in program) This is a case where the transmission is temporarily suspended and there is no broadcast signal input to the reception conversion unit 4a), “ stop ( there is a broadcast signal input to the reception conversion unit 4a, but the reception conversion unit 4a or the transmission conversion unit 4b). And when there is no signal output from the amplifying unit 7) ”.

  For example, when the total number of amplification determination channels is 4, the total number of reception determination channels (shown as “RF input” in FIG. 3) is always 4 (output for four channels is output from the amplification unit 7). Therefore, it is determined that all four channels are being broadcast. When the total number of amplification determination channels is 3, when the total number of reception determination channels is 3, three channels are being broadcast, one channel is inactive, and the total number of reception determination channels is 4. In some cases, 3 channels are being broadcast and 1 channel is stopped. A determination can be made for each of the cases where the total number of reception determination channels is 2, 1, 0. As for the determination result, for example, the determination result can be output to a predetermined report destination such as a remote monitoring center or a display output for notifying the determination result can be performed.

(Control of channel monitoring controller 20-Abnormality detection of amplifier 7)
In FIG. 2, the channel monitoring control unit 20 detects an abnormality in the amplification unit 7 based on the total number of reception determination channels detected in step SA-4 and the signal level at the signal output position of the amplification unit 7. To do.

  More specifically, the abnormality detection calculates the appropriate control range of the signal level fluctuation at the signal output position of the amplifier 7 based on the total number of reception determination channels (step SA-9), and the actual signal level If it exceeds the appropriate control range, it is determined that an abnormality has occurred (step SA-10, Yes), and abnormality control is performed (step SA-11). As the abnormality control, for example, when the abnormality is detected, the channel monitoring control unit 20 outputs the control signal to the switching unit 8 to switch the amplification unit 7 from the active side to the standby side. Furthermore, when an abnormality determination is detected, the channel monitoring control unit 20 outputs an abnormality signal to a predetermined reporting destination such as a remote monitoring center as an abnormality control to notify that an abnormality has occurred. Good.

For example, when the control range of the signal level fluctuation is about ± 10%, the appropriate control range is set to P when the output per channel is P and the total number of reception determination channels is N. The threshold TH _min is in the range of 90% to P (N−1) / N × 100%, and the upper limit threshold TH _maz of the appropriate control range is in the range of 110% to P (N + 1) / N × 100%. To do. Specifically, the lower limit threshold when the output per channel is 0.3 w is 90% to 75% with respect to 0.3 w when the total number of reception determination channels is 4, and the total number of reception determination channels is 3 90% to 67% with respect to 0.3w, 90% to 50% with respect to 0.3w when the total number of reception determination channels is 2, and 0.3w when the total number of reception determination channels is 1. 90% to 0%. The upper threshold when the output per channel is 0.3 w is 110% to 125% with respect to 0.3 w when the total number of reception determination channels is 4, and when the total number of reception determination channels is 3. 110% to 133% with respect to 0.3w, 110% to 150% with respect to 0.3w when the total number of reception determination channels is 2, and 110% with respect to 0.3w when the total number of reception determination channels is 1. 200%. As described above, as the total number of reception determination channels decreases, the lower limit threshold and the upper limit threshold are widened, so that fluctuations in the appropriate control range associated with the increase or decrease in the number of channels can be absorbed, and abnormality detection can be performed appropriately.

(Effect of this embodiment)
According to such a configuration, the total number of reception determination channels is detected, and the amplification factor in the AGC amplifier of the amplifying unit 7 is controlled according to the total number of reception determination channels without using a multichannel wattmeter. It is possible to appropriately control the AGC output level at the time of collective amplification.
Further, by determining the status of each channel based on the total number of amplification determination channels and the total number of reception determination channels, the broadcast state (relay state) in the relay broadcast station device 1 is notified in detail to a remote monitoring station or the like. can do.
Further, based on the total number of reception determination channels and the signal level at the signal output position of the amplification unit 7, an abnormality of the amplification unit 7 is detected, and when the abnormality is detected, the amplification unit 7 is switched from the active side to the standby side, Broadcasting can be continued even when an abnormality occurs in the amplification unit 7, and the reliability of broadcast relay can be improved.
Further, by calculating the appropriate control range of the signal level fluctuation at the signal output position of the amplification unit 7 based on the total number of reception determination channels, the fluctuation of the appropriate control range accompanying the increase or decrease in the number of channels is absorbed, and the abnormality is detected. Can be performed properly.

[III] Modifications to the Embodiments Although the embodiments of the present invention have been described above, the specific configurations and means of the present invention are within the scope of the technical idea of each invention described in the claims. Can be arbitrarily modified and improved. Hereinafter, such a modification will be described.

(About problems to be solved and effects of the invention)
First, the problems to be solved by the invention and the effects of the invention are not limited to the above-described contents, and the present invention solves the problems not described above or has the effects not described above. There are also cases where only some of the described problems are solved or only some of the described effects are achieved.

(About control flow and parameters)
The control flow in FIG. 2 is an example, and the control processing can be performed in another order unless otherwise specified. For example, the abnormality determination of the reception conversion unit 4 a and the transmission conversion unit 4 b may be performed after the abnormality determination of the amplification unit 7. The numerical values and mathematical expressions shown in the calculation of the control level of the amplifying unit 7 and the output level of the amplifying unit 7 are merely examples, and any different numerical values and mathematical expressions can be used.

  The present invention can be applied to a relay broadcast station apparatus that relays broadcast signals. In particular, in an MCPA relay broadcast station apparatus, output level fluctuation control and relay broadcast station apparatus abnormality detection can be performed without using a multichannel wattmeter. Useful to do.

It is a block diagram which shows the structure of the relay broadcast station apparatus which concerns on embodiment of this invention. It is a figure which shows the flowchart of control of a channel monitoring control part. It is a figure which shows the control table used for control of a channel monitoring control part. It is a block diagram which shows the structure of the conventional MCPA system relay broadcast station apparatus. It is a block diagram which shows the structure of the relay broadcast station apparatus of the conventional SCPA system.

Explanation of symbols

1, 100, 120 Relay broadcast station apparatus 2, 101, 121 Reception antenna 3, 102 Demultiplexer 4, 103, 123 Reception / transmission conversion unit 4a, 103a, 123a Reception conversion unit 4b, 103b, 123b Transmission conversion unit 4c, 103c 123d Switching unit 5, 104, 124 Synthesizer 6, 105, 122 Divider 7, 106, 123c Amplifying unit 8, 107 Switching unit 9, 108, 125 Output filter 10, 109, 126 Transmitting antenna 20 Channel monitoring control unit 110 Multi-channel power meter

Claims (6)

A plurality of reception conversion means for receiving and converting signals of a plurality of channels for each channel, a plurality of transmission conversion means for transmitting and converting the reception-converted signals for each channel, and a plurality of transmission-converted signals of the plurality of channels at once. In a relay broadcast station apparatus comprising amplification means for amplifying
Detecting the number of channels based on the level of the signal in the previous stage of the amplification means, calculating the number of channels based on the level of the output signal from the amplification means , and the number of the detected channels ; Channel monitoring control means for controlling the relay broadcast station apparatus according to the calculated number of channels ,
A relay broadcast station apparatus comprising: The channel monitoring control means includes
A total output level calculated by multiplying the number of the channels detected based on the signal level in the previous stage of the amplification means by a predetermined individual output level for each channel is set as the output level of the amplification means And
Calculating the number of channels by dividing the level of the output signal from the amplification means by a predetermined individual output level per each channel;
According to the number of channels detected based on the level of the signal in the previous stage of the amplification means and the number of channels calculated based on the level of the output signal from the amplification means, the broadcast status for each channel is determined. Determining and controlling the relay broadcast station device according to the determined broadcast status;
The relay broadcast station apparatus according to claim 1. The channel monitoring control means detects the number of channels based on the level of an input signal to each of the plurality of reception conversion means;
The relay broadcast station apparatus according to claim 1 or 2. The channel monitoring control unit is configured to determine the reception conversion unit and the transmission conversion unit based on an input signal level to each of the plurality of reception conversion units and an output signal level from each of the plurality of transmission conversion units. Detecting abnormalities in the
The relay broadcast station apparatus according to any one of claims 1 to 3. A plurality of amplifying means and a switching means for switching the plurality of amplifying means to each other,
The channel monitoring control means detects an abnormality of the amplification means based on the number of the detected channels and the level of the output signal from the amplification means, and when the abnormality is detected, the switching means Switching the amplification means to each other via
The relay broadcast station apparatus according to any one of claims 1 to 4. The channel monitoring control unit calculates a control range of the signal level in the amplification unit based on the number of the detected channels, and the level of the output signal from the amplification unit exceeds the calculated control range. Determining that the amplification means is abnormal if
The relay broadcast station apparatus according to claim 5 .

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