JP2007036784A - Transmitting device for radio line for broadcasting, and phase control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission device for a radio line for broadcasting that facilitates phase synchronization for seamless switching, and to provide a phase control method thereof. <P>SOLUTION: In transmitters 1 and 2, carriers input from modulators of respective systems are input to a switch 9 via internal phase units 21 and 22, and amplifiers 31 and 32. Outputs of the amplifiers 31 and 32 are input to a mixer 5 and a synthesizer 6 connected to the mixer 5 in parallel, and the output of the mixer 5 is fed back to the phase units 21 and 22 via a hybrid 4. The signal generated by putting together (adding) the outputs of the amplifiers 31 and 32 by the synthesizer 6 is output to a level decision part 7, which decides the level of the signal and outputs an inversion control signal to a control terminal C of an inversion part 8 inserted between the hybrid 4 and mixer 5 to control the polarity of the signal from the mixer 5, thereby performing phase control over the respective phase units. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a broadcasting wireless channel transmission apparatus including a working system and a standby system that perform seamless switching, and a phase control method thereof.

  In a broadcast radio network device that relays broadcast waves, seamless switching without line disconnection is performed when switching from the active system to the standby system (system switching).

  For this reason, it is a necessary condition for seamless switching that control is performed so that the carrier wave frequency and phase of the transmitted radio wave do not change so that the signals before and after switching are continuous at the time of system switching. In the broadcast transmitter, for seamless switching, the transmission radio waves transmitted in both the active and standby systems are demodulated once into broadcast program signals, the phase difference between them is measured, the phase difference is adjusted, and the signal is modulated and transmitted again. However, signal processing becomes complicated (for example, Patent Document 1).

  In addition, in the relay radio network apparatus, the apparatus scale must be reduced. Therefore, in order to establish carrier frequency (phase) synchronization instead of the above-described method, the transmission radio waves (in the active and standby relay transmitters ( There is a method in which the phase of the carrier wave) is measured and compared with a reference signal output from a common oscillator in the active system and the standby system, and the phases are aligned. (For example, patent document 2).

However, although the transmission / reception device for the broadcast radio line is originally configured with a circuit configuration in which a control signal is not connected to the internal circuit from the outside, both of these methods are for performing timing control on the active and standby systems. There is a problem that the signal processing of the transmitter becomes complicated because a signal for performing control processing must be input / output between the common oscillator, that is, the pre-processing circuit of the two transmitters and the outside. It was.
JP 2004-96468 A (page 7, FIG. 1) Japanese Patent No. 3536831 (6th page, Fig. 1)

  Conventionally, in a broadcasting wireless channel transmission device, it has been necessary to align the phase of a carrier wave of a relayed signal between a working system and a standby system in order to switch seamlessly, but a reference signal is supplied from a common oscillator. There is a problem that the signal processing of the transmitters becomes complicated because the process of aligning the phases of the outputs of the two transmitters is performed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a transmission device for a broadcast radio channel and a phase control method thereof for easy phase synchronization for seamless switching.

  In order to achieve the above-mentioned object, a broadcasting wireless channel transmission device according to the present invention is a broadcasting wireless channel transmission device having a working transmission line and a standby transmission system, each of which outputs a carrier wave via a phase shifter. A second transmitter, a switch that connects one of the first and second transmitters to the antenna as an active device, and each carrier wave output from the first and second transmitters are mixed. A mixer that outputs a mixer signal to an inverting unit, each terminal that outputs the mixer signal as an input, and a control signal terminal. The mixer signal that is input according to the inverted control signal that is input to the control signal terminal The polarity of the output signal is output as it is or inverted, and the mixer signal input via the inverter is branched into two to output one as the phase control signal of the phase shifter of the first transmitter. , The other A hybrid that outputs as a phase control signal of a phase shifter of the transmitter 2, a synthesizer that is connected in parallel to the mixer and that synthesizes the input carrier waves, and a signal output from the synthesizer A level determination unit that monitors the level and generates the inverted control signal and outputs the inverted control signal to the control signal terminal when the level is equal to or lower than a predetermined level, and each level of the first and second transmitters The phase shifter performs feedback control on the phase of the output carrier wave using each mixer signal input via the hybrid as an error signal.

  Also, the phase control method for a broadcast radio channel transmission apparatus according to the present invention is a phase control method for a broadcast radio channel transmission apparatus having a working and a backup transmission system, wherein each of the transmission devices is connected via a phase shifter. First and second transmitters that output a carrier wave, a switcher that connects one of the first and second transmitters to the antenna as an active device, a mixer, an inverting unit, a hybrid, and a synthesis And a level determination unit, and the mixer receives each carrier wave output from the first transmitter and the second transmitter, and mixes the inputted carrier wave to the inversion unit. The inverting unit is connected between the mixer and the hybrid and includes a control signal terminal, and the polarity of the input mixer signal according to the inverted control signal input to the control signal terminal The The hybrid outputs the signal to the hybrid as it is or is inverted. The hybrid splits the output signal of the mixer input from the inverter into two and uses one as the phase control signal to the phase shifter of the first transmitter The other is output as a phase control signal to the phase shifter of the second transmitter. The combiner is connected in parallel to the mixer, and the level determination is performed on a signal obtained by combining the input carriers. The level determination unit monitors the level of the signal input from the combiner and generates the inversion control signal instructing the inversion when the level is equal to or lower than a predetermined level, and the control signal terminal The phase shifters of the first and second transmitters perform feedback control on the phase of each output carrier wave using the mixer signal input via the hybrid as an error signal. Phase control method of a transmitting apparatus of the radio channel for broadcast, wherein.

  ADVANTAGE OF THE INVENTION According to this invention, the transmission apparatus of the radio | wireless line for broadcasting for easy phase synchronization for performing seamless switching, and its phase control method can be provided.

  Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a functional block diagram for explaining phase control of a transmitter of a radio network apparatus according to a first embodiment of the present invention. The outputs of two transmitters are input to a mixer, and the output voltage of the mixer is This is a method of performing phase synchronization by feeding back to the phase shifter of the standby transmitter.
In FIG. 1, the transmission system is composed of a system of each of the transmitter 1 and the transmitter 2, the hybrid 4 that demultiplexes the output signal of the mixer 5 to the transmitters 1 and 2, and the output of the transmitters 1 and 2. A mixer 5 that receives a signal and outputs the mixed signal as a mixer signal, and a switch 9 that switches the output of the transmitters 1 and 2 and connects one of them to an antenna are provided.

  In the transmitter 1 and the transmitter 2, the carrier wave input from the modulator of each system is amplified by the phase shifters 21 and 22 and the amplifiers 31 and 32, and the output is input to the switch 9. The outputs of the amplifiers 31 and 32 are connected to the mixer 5, and the output of the mixer 5 is fed back to each phase shifter 21 and 22 of the transmitter via each hybrid 4 and the inverting units 11 and 12. The phase shifters 21 and 22 are controlled so that the phase difference is eliminated by the signal voltage fed back.

  The transmitters 1 and 2 operate as either active or standby, but the carrier wave input to each of the transmitters 1 and 2 is supplied from the modulator of each system. Although these modulation signals and carrier waves are not shown in the figure, they are generated based on the signals of two systems, in other words, the common reference oscillator for current use and backup, so the cable and the frequency are originally the same regardless of whether the frequency and phase are the same. At the final stage due to the accumulation of slight differences in the length and signal processing circuit, there is a particular phase shift between the two, which hinders seamless switching of broadcast waves.

  Conventionally, a method has been used in which the output signal of the reference oscillator is compared with the outputs (carrier waves) from the two transmitters at the final stage to align the phases of both outputs, but the circuit becomes complicated and the scale is large. As described above, there are problems such as.

FIG. 2 is a diagram showing the relationship between the carrier waves of the two transmitters 1 and 2 input to the mixer 5 in FIG. 1 and the output of the mixer 5 which is a mixed output thereof.
2A is an example of the phase difference of the carrier wave input to the mixer from two transmitters, and FIG. 2B is the phase difference of the carrier wave input to the mixer 5 and the output of the mixer 5. (Note that FIG. 2 (c) adds the phase difference between the two carriers input to the mixer in the second embodiment described later and the two carriers input by the combiner described later. It shows the relationship with the output signal.)

  When the transmitter 1 is used as a reference, when the two carrier waves have the same amplitude and are in the positive phase, the output of the mixer 50 is as shown by the solid line in FIG. That is, when the amplitude and phase of the outputs of the two transmitters are the same, the output of the mixer 5 becomes “0”. Therefore, if the phase shifters 21 and 22 are feedback-controlled so that the output of the mixer 5 becomes 0, For example, the phase of the carrier wave output from each of the active transmitter 1 and the spare transmitter 2 coincides and seamless switching can be performed.

  On the other hand, when the active system and the standby system are switched, the reference carrier wave is switched, so that the phase relationship is reversed as shown by the dotted line in FIG. Since the output voltage of the mixer 5 is 0 when the phase is 0 degrees and 180 degrees, if feedback control is performed with the mixer signal having the same polarity, the correspondence between the signal fed back from the mixer 5 and the rotation direction of the phase shifter is reversed. Therefore, there is a case where an operation for adjusting to the opposite phase (180 degrees) is started at the time of switching.

  In FIG. 1, in order to avoid this malfunction, the polarity of the signal to be fed back to the inverting units 11 and 12 by supplying the working preliminary switching signal to the inverting units 11 and 12 so as to interlock with the changeover switch 9 when switching between the working system and the standby system. Inverted. (In this case, the transmitter 1 is the active system.) The inverting units 11 and 12 indicate whether the signal input from the internal changeover switch has the same polarity or the inverted polarity according to the working standby switching signal. Is switched to output.

FIG. 3 is a block diagram showing an internal functional configuration of the phase shifters 21 and 22.
In FIG. 3, each of the phase shifters 21 and 22 includes a drive amplifier 2A and a phase shifter 2B in which the phase shift amount of the output of the carrier wave input by the control voltage from the drive amplifier 2A is controlled.

  The drive amplifier 2A has two input terminals 2i1 and 2i2 and an output terminal 2o, so that there is no difference between the input voltages of 2i1 and 2i2, in other words, the control voltage is output so that the mixer signal becomes “0” volts. Is fed back to the control terminal 5c of the phase shifter 2B for feedback control.

  That is, a reference voltage (here, 0 volt of the ground potential) is applied to the input terminal 2i1, and the output of the mixer 5 is applied to the other input terminal 2i2 as an error voltage via the hybrid 4. . If the control voltage generated from the error voltage is output from the output terminal 2o and the output of the mixer is 0 volts, the phase difference between the transmission radio waves (carrier waves) between the two transmitters 1 and 2 Feedback control is performed so that there is no. As a result, the carrier waves input to the phase shifters 21 and 22 are each subjected to a required phase shift, and are feedback controlled so that the phases of the carrier waves output from the transmitter 1 and the transmitter are aligned.

FIG. 4 is a block diagram showing a functional configuration of the transmission system of the radio network device according to the second embodiment of the present invention.
In FIG. 4, the radio network device includes a transmitter 1 in two systems, a mixer 5 connected to the transmitter 2, and a combiner 6, a hybrid 4, a level determination unit 7, an inversion unit 8, and two transmitters. And a switch 9 for switching the output and connecting to the antenna.

  In the transmitter 1 and the transmitter 2, the carrier wave input from the modulator of each system is input to the phase shifters 21 and 22 of the transmitters 1 and 2, and their outputs are amplified by the amplifiers 31 and 32 and switched. Is output to the device 9.

  The outputs of the amplifiers 31 and 32 are also connected to the mixer 5, and the output of the mixer 5 is input to the input terminal i of the inverting unit 8. The output terminal o of the inverting unit 8 is connected to the hybrid 4 and branched by the hybrid 4, and one of the output signals of the mixer 5 is fed back to the phase shifter 21 and the other to the phase shifter 22. The inside of the phase shifters 21 and 22 is as shown in FIG.

  In FIG. 4 again, the outputs of the amplifiers 31 and 32 are also input to the synthesizer 6 connected in parallel to the mixer 5. The combiner 6 outputs a signal obtained by combining (adding) the outputs of the amplifiers 31 and 32 to the level determination unit 7. The level determination unit 7 inputs an inversion control signal to the control terminal c of the inversion unit 8 when the input signal is lower than a predetermined level as described later, and outputs the output signal of the mixer 5 output from the inversion unit 8. Inverted, the phase shifters 21 and 22 perform phase control correctly without being out of phase.

  That is, in FIG. 4, when the amplitude and phase of the outputs of two transmitters are the same, the output of the mixer 5 is “0”, and the output of the synthesizer 6 is “2C” at that time. In other words, the output of the synthesizer 6 corresponds to the solid line in FIG. 2B, and the carrier wave input to the mixer 5 is added. Therefore, if the phases of the two carrier waves are aligned, the output of the synthesizer 6 is maximum. “2C”.

  On the other hand, as the phase shifts, the output level decreases from the maximum value “2C” of the phase difference 0 degree to the minimum value “0” of the phase difference 180 degrees in the opposite phase direction. When the phase difference exceeds ± 90 degrees, the relationship becomes opposite to each other. Therefore, the output level of the synthesizer 8 is observed even when the active system is switched to the standby system, and the predetermined level (here, “C”) or higher. By determining the following, it can be determined whether the mixer output relationship is reverse phase or normal phase.

  When the signal of the synthesizer 6 is input and the level is “C” or higher, the level determination unit 7 outputs an inversion control signal of “0” that maintains the polarity of the mixer signal input by the inversion unit 8. Output. If the level is equal to or lower than “C”, “1” is output to invert and output the signal of the mixer 5. The output of the inversion control signal of the level determination unit 7 is input to the control terminal c of the inversion unit 8.

  The inverting unit 8 includes a two-circuit switching switch 81 and an inverting circuit 82 inside. One of the outputs of the mixer 5 input to the input terminal i of the inverting unit 8 is connected to the input side of the inverting circuit 82, and the output side of the inverting circuit 82 is connected to one switching terminal of the switch 81. On the other hand, the other output of the mixer 5 input to the input terminal i is connected to the other switching terminal of the switch 81.

  The control terminal c of the inverting unit 8 controls the connection destination of the common terminal of the switch 81. If the inverting control signal is “0”, the signal from the mixer 5 is directly output to the output terminal o of the inverting unit 8. On the contrary, if the inversion control signal is “1”, the output signal of the mixer 5 through the inversion circuit 82 is output from the switch 81 to the output terminal o.

  Therefore, in the block diagram shown in FIG. 4, it is not necessary to supply the working standby switching signal to the inside of the transmitter in connection with the phase control. Even if the phase is reversed, the polarity of the signal of the mixer 5 applied to the phase shifters 21 and 22 is automatically inverted, so that the phase adjustment is performed so that there is no phase difference between the outputs of the two transmitters. I can do it.

  In the second embodiment, the control for aligning the phases of the active system and the standby system performs quick feedback control so that the output of the mixer 5 is set to “0” in each of the active system and the standby system. Instability may occur due to the interaction between the system and the standby system.

  Therefore, as a third method of matching the phases, the mutual influence may be prevented by matching the phase of the output of the standby system with the phase of the output of the active system as a reference.

FIG. 5 is a block diagram showing the functional configuration of the transmission system of the wireless network device according to the third embodiment of the present invention.
FIG. 5 shows a method for performing phase control using the designation signals for the active and standby systems.
In FIG. 5, ground switches 211 and 212 are inserted between the output of the hybrid 4 and the feedback loop to the phase shifters 21 and 22. Then, a working standby switching signal is supplied to the control terminals sc of the ground switches 211 and 212 so as to be interlocked with the switch 9.

FIG. 6 is a connection diagram of the phase shifters 21 and 22 (drive amplifiers 2A and 2B) and the ground switches 211 and 212.
In FIG. 6, the common terminals of the ground switches 211 and 212 are connected to the input terminals 2i2 of the drive amplifiers 2A and 2B, respectively. One of the switching terminals of each of the ground switches 211 and 212 is grounded, and the other is connected to the hybrid 4.

  The ground switch of the transmission system designated as the working system (here, the ground switch 211) is configured by grounding (that is, 0 volts) the input terminal 2i2 of the drive amplifier 2A of the phase shifter 21 of the transmitter 1. The voltages at both input terminals of the drive amplifier 2A are set to the ground potential “0” volts which is the reference voltage.

  That is, since the voltages at both input terminals are both “0” volts, the feedback by the output voltage of the mixer 5 is stopped in the drive amplifier 2A, and the phase shift by the drive amplifier 2A does not occur in the phase shifter 21.

  Then, with reference to the carrier wave output of the active transmitter 1, the standby transmitter 2 performs a feedback operation in which the phase shifter 22 follows the output of the mixer 5, that is, the output of the active transmitter. It will be done. Except for the above points, the operations of the first and second embodiments are the same. However, since phase tracking is performed with reference to the output of the active system only in the standby system, it occurs between the active and standby phase shifters. This has the effect of preventing phase control hunting.

FIG. 7 also shows that the phase shifter 22 of the standby transmitter tracks the output phase of the carrier wave output from the active transmitter as in the third embodiment. It is a figure which shows the 4th Example.
In FIG. 7, the inverting units 11 and 12 in the first embodiment of FIG. 1 are replaced with ground switches 211 and 212. Details of the operation and the like can be easily inferred from the description of the third embodiment, and thus description thereof will be omitted.

  As described above, in the embodiment of the present invention, the phase of the carrier waves output from the two transmitters can be directly compared without comparing the output phases of the two transmitters with the reference oscillator. Therefore, phase synchronization required for seamless switching can be easily performed.

The block diagram which shows the function structure of the transmission system of the radio | wireless line apparatus which concerns on 1st Example of this invention. The figure which shows the relationship between the carrier wave of two transmitters input into a mixer, and a mixer output. The block diagram which shows the function structure inside a phase shifter. The block diagram which shows the function structure of the transmission system of the radio | wireless line apparatus which concerns on 2nd Example of this invention. The block diagram which shows the function structure of the transmission system of the radio | wireless circuit apparatus which concerns on 3rd Example of this invention. The connection diagram between each phase shifter and each ground switch. The block diagram which shows the function structure of the transmission system of the radio | wireless circuit apparatus which concerns on 4th Example of this invention.

Explanation of symbols

1, 2 Transmitters 21, 22 Phaser 211, 212 Ground switch 31, 32 Amplifier 4 Hybrid 5 Mixer 6 Synthesizer 7 Level determiner 8 Inverting unit 9 Switch

Claims (8)

In a transmission device for a broadcast radio line equipped with a working transmission line and a spare transmission line,
First and second transmitters each for outputting a carrier wave via a phase shifter;
A switch for connecting one of the first and second transmitters to the antenna as an active device;
A mixer that outputs a mixer signal obtained by mixing the carrier waves output from the first and second transmitters to a hybrid;
A hybrid that bifurcates the output mixer signal and outputs one as a phase control signal for the phase shifter of the first transmitter and outputs the other as a phase control signal for the phase shifter of the second transmitter When,
When the transmitter connected to the phaser of the first and second transmitters and connected to the phaser in conjunction with the switcher is in use, the polarity of the input mixer signal is left as it is. And first and second inversion units that invert and output in the case of a spare,
Each phase shifter of the first and second transmitters is
An apparatus for transmitting a radio channel for broadcasting, wherein each mixer signal input via each inverting unit is used as an error signal to feedback control the phase of the output carrier wave. In a transmission device for a broadcast radio line equipped with a working transmission line and a spare transmission line,
First and second transmitters each for outputting a carrier wave via a phase shifter;
A switch for connecting one of the first and second transmitters to the antenna as an active device;
A mixer that outputs a mixer signal obtained by mixing the carrier waves output from the first and second transmitters to an inverting unit;
Each terminal for inputting and outputting the mixer signal and a control signal terminal are provided, and the polarity of the input mixer signal is output as it is or after being inverted according to the inverted control signal input to the control signal terminal. Reversing part,
The mixer signal input via the inverting unit is branched into two and one is output as a phase control signal of the phase shifter of the first transmitter, and the other is phase control of the phase shifter of the second transmitter A hybrid that outputs as a signal,
A synthesizer which is connected in parallel to the mixer and outputs a signal obtained by synthesizing the input carrier waves;
When the level of a signal output by the combiner is monitored and below a predetermined level, the inverting unit includes the level determining unit that generates the inverted control signal and outputs the inverted control signal to the control signal terminal,
Each phase shifter of the first and second transmitters is
An apparatus for transmitting a radio channel for broadcasting, wherein a mixer signal input via the hybrid is used as an error signal for feedback control of the phase of the output carrier wave. In a transmission device for a broadcast radio line equipped with a working transmission line and a spare transmission line,
First and second transmitters each for outputting a carrier wave via a phase shifter;
A switch for connecting one of the first and second transmitters to the antenna as an active device;
A mixer that outputs a mixer signal obtained by mixing the carrier waves output from the first and second transmitters to an inverting unit;
Each terminal for inputting and outputting the mixer signal and a control signal terminal are provided, and the polarity of the input mixer signal is output as it is or after being inverted according to the inverted control signal input to the control signal terminal. Reversing part,
The mixer signal input via the inverting unit is branched into two and one is output as a phase control signal of the phase shifter of the first transmitter, and the other is phase control of the phase shifter of the second transmitter A hybrid that outputs as a signal,
A synthesizer which is connected in parallel to the mixer and outputs a signal obtained by synthesizing the input carrier waves;
When the level of the signal output from the combiner is monitored and below a predetermined level, a level determination unit that generates the inversion control signal in the inversion unit and outputs it to the control signal terminal;
When the transmitter, which is provided at the input of each phase shifter of the first and second transmitters and is connected to the switcher in conjunction with the switcher, is used for actual use, instead of the input mixer signal The phase shifters of the first and second transmitters are provided with first and second ground switches that output a ground potential signal to and output the input mixer signal as it is when used as a spare. ,
An apparatus for transmitting a radio channel for broadcasting, wherein a mixer signal input via the hybrid is used as an error signal for feedback control of the phase of the output carrier wave. In a transmission device for a broadcast radio line equipped with a working transmission line and a spare transmission line,
First and second transmitters each for outputting a carrier wave via a phase shifter;
A switch for connecting one of the first and second transmitters to the antenna as an active device;
A mixer that outputs a mixer signal obtained by mixing the carrier waves output from the first and second transmitters to a hybrid;
A hybrid that bifurcates the output mixer signal and outputs one as a phase control signal for the phase shifter of the first transmitter and outputs the other as a phase control signal for the phase shifter of the second transmitter When,
When the transmitter, which is provided at the input of each phase shifter of the first and second transmitters and is connected to the switcher in conjunction with the switcher, is used for actual use, instead of the input mixer signal A ground potential signal is output to the first and second ground switches for outputting the input mixer signal as it is when used as a spare,
Each phase shifter of the first and second transmitters is
An apparatus for transmitting a radio channel for broadcasting, wherein each mixer signal input via each ground switch is used as an error signal for feedback control of the phase of the output carrier wave. In a phase control method for a transmission device for a broadcast radio channel having a working and a backup transmission system,
The transmitter includes a first transmitter and a second transmitter that output a carrier wave via a phase shifter, and a switch that connects one of the first transmitter and the second transmitter to an antenna as an active device, A mixer, an inversion unit, a hybrid, a synthesizer, and a level determination unit;
The mixer receives each carrier wave output from the first transmitter and the second transmitter, and outputs a mixer signal obtained by mixing the inputted carrier waves to the inverting unit,
The inversion part is
The control signal terminal is connected between the mixer and the hybrid, and in accordance with an inversion control signal input to the control signal terminal, the polarity of the input mixer signal is directly or inverted Output to the hybrid,
The hybrid
The output signal of the mixer input from the inverting unit is branched into two and one is output as a phase control signal to the phase shifter of the first transmitter, and the other is output to the phase shifter of the second transmitter. Output as a phase control signal,
The synthesizer
Connected in parallel to the mixer, and outputs a signal obtained by synthesizing each input carrier wave to the level determination unit,
The level determination unit
When the level of the signal input from the combiner is monitored and below a predetermined level, the inversion control signal for instructing the inversion is generated and output to the control signal terminal,
Each phase shifter of the first and second transmitters is
A phase control method for a transmission apparatus for a broadcast radio channel, wherein the phase of each carrier wave to be output is feedback-controlled using an input mixer signal via the hybrid as an error signal. In a phase control method for a transmission device for a broadcast radio channel having a working and a backup transmission system,
The transmitter includes a first transmitter and a second transmitter that output a carrier wave via a phase shifter, and a switch that connects one of the first transmitter and the second transmitter to an antenna as an active device, A mixer, an inversion unit, a hybrid, a synthesizer, a level determination unit, and first and second brother ground switches;
The mixer receives each carrier wave output from the first transmitter and the second transmitter, and outputs a mixer signal obtained by mixing the inputted carrier waves to the inverting unit,
The inversion part is
The control signal terminal is connected between the mixer and the hybrid, and in accordance with an inversion control signal input to the control signal terminal, the polarity of the input mixer signal is directly or inverted Output to the hybrid,
The hybrid
The output signal of the mixer input from the inverting unit is branched into two and one is output as a phase control signal to the phase shifter of the first transmitter, and the other is output to the phase shifter of the second transmitter. Output as a phase control signal,
The synthesizer
Connected in parallel to the mixer, and outputs a signal obtained by synthesizing each input carrier wave to the level determination unit,
The level determination unit
When the level of the signal input from the combiner is monitored and below a predetermined level, the inversion control signal for instructing the inversion is generated and output to the control signal terminal,
The first and second ground switches are:
When the transmitter, which is provided between the hybrid and each phaser of the first and second transmitters and is connected in conjunction with the switcher, is used for current use, the input is made. Output a ground potential signal instead of the mixer signal, and when used as a spare, output the input mixer signal as it is,
Each phase shifter of the first and second transmitters is
A phase control method for a transmission apparatus for a broadcast radio channel, wherein the phase of each output carrier is feedback-controlled using the input mixer signal as an error signal. In a phase control method for a transmission device for a broadcast radio channel having a working and a backup transmission system,
The broadcasting wireless channel transmission device includes first and second transmitters, a switcher, a mixer, a hybrid, and first and second inversion units that output carrier waves via phase shifters, respectively. Prepared,
The switch connects one of the first and second transmitters to an antenna as an active one,
The mixer is
A mixer signal obtained by mixing the carrier waves output from the first and second transmitters is output to a hybrid;
The hybrid
Branching the input mixer signal into two and outputting one as the phase control signal of the phase shifter of the first transmitter, and outputting the other as the phase control signal of the phase shifter of the second transmitter;
The first and second inversion units are provided at the inputs of the phase shifters of the first and second transmitters, and a transmitter to which the first and second inversion units are connected in conjunction with the switcher is used for current use. , Output the input mixer signal as it is, invert the output when used as a reserve,
The phase shifter of each of the first and second transmitters performs feedback control of the phase of the carrier wave to be output using each mixer signal input from each of the inverting units as an error signal. Phase control method for the transmitter of the present invention. In a phase control method for a transmission device for a broadcast radio channel having a working and a backup transmission system,
The broadcasting wireless line transmission device includes a first transmitter, a second transmitter, a switch, a mixer, a hybrid, and first and second ground switches, each of which outputs a carrier wave via a phase shifter. Prepared,
The switch is
Either one of the first and second transmitters is connected to the antenna as active,
The mixer is
A mixer signal obtained by mixing the carrier waves output from the first and second transmitters is output to a hybrid;
The hybrid
Branching the output mixer signal into two and outputting one as the phase control signal of the phase shifter of the first transmitter, and outputting the other as the phase control signal of the phase shifter of the second transmitter;
The first and second ground switches are
Provided between the hybrid and each phase shifter of the first and second transmitters, and when the transmitter to which it is connected in conjunction with the switch is used for actual use, is input. Output the ground potential signal instead of the mixer signal, and when used as a reserve, output the input mixer signal as it is,
Each phase shifter of the first and second transmitters is
A phase control method for a transmission device for a broadcast radio channel, wherein each mixer signal input via each ground switch is used as an error signal to feedback control the phase of the carrier wave to be output.

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