JP4664764B2 - Gap filler device - Google Patents

Description

  The present invention relates to a gap filler device that amplifies a signal level of a broadcast signal received by a receiving antenna and retransmits the signal from the transmitting antenna.

  In recent years, the present applicant has proposed various techniques as a gap filler device that amplifies a signal level of a broadcast signal received by a receiving antenna and retransmits the signal from the transmitting antenna (for example, Patent Document 1). , See Patent Document 2).

In such a gap filler device, the device main body is activated and a drive signal is supplied to the amplifier, whereby the broadcast signal is retransmitted in a signal level amplified state. In order to prevent unnecessary noise from being emitted, control is made so that the signal level of the retransmitted broadcast signal does not become too high, or transmission is blocked when the device is not in a stable operating state. It is common to perform such control. Specifically, depending on the signal level of the retransmitted broadcast signal, the signal level of the broadcast signal input to the amplifier is attenuated by an attenuator or the like, or the path through which the broadcast signal is input to the amplifier is determined. The control is to open with a switch.
JP 2005-045728 A JP 2005-151469 A

  However, since the isolation of the switch and the attenuator cannot be made sufficiently large (in the case of a transmission signal frequency of 2.6 GHz, about 20 dB each), depending on the gain of the transmission amplifier, a leaked signal may be transmitted from the transmission antenna. May be emitted.

  Furthermore, immediately after the device is started (including restart), the operation state of the control unit that controls the operation of the entire device is not stable. The signal level of the broadcast signal may become too high.

  In such a case, the broadcast signal to be retransmitted is radiated as unnecessary noise around the transmitting antenna, and the broadcast signal of a large signal level continuously circulates in the device. There is a risk of damaging the configuration (eg, an amplifier, etc.).

  The present invention is to solve such a problem, and its purpose is to prevent the signal level of the retransmitted broadcast signal from becoming too high immediately after the gap filler device is started. is there.

In order to solve the above problems, a gap filler device according to a first configuration receives a broadcast signal transmitted from a broadcast station side by a receiving antenna, and amplifies the received broadcast signal with a signal level by an amplifier. A gap filler device that retransmits using a transmission antenna, and includes an amplification suppression unit that suppresses an amplification effect of the amplifier on a broadcast signal until a predetermined period elapses after the gap filler device is activated. It is characterized by that.

  In this configuration, the “predetermined period” in which the amplification suppression means suppresses the amplification action by the amplifier is, for example, so that the operation state is stabilized after the gap filler device is activated and the broadcast signal does not become too large. For example, a period that is assumed to be required until the control for performing the control is appropriately performed may be used.

Further, as a configuration for suppressing the amplification action of the amplifier by this amplification suppression means, for example, the following second configuration can be considered.
The gap filler device according to the second configuration receives a command signal from a control unit that controls the operation of the entire gap filler device, and starts supplying a drive signal for driving the amplifier to the amplifier. The amplification suppression means is configured to block the arrival of the command signal from the control unit to the drive supply unit until a predetermined period elapses after the control unit is activated. ing.

In this configuration, the configuration for the amplification suppression means to “shut off the arrival of the command signal to the drive supply means” is not particularly limited, but a specific example is, for example, the third configuration. It is possible.

In the gap filler device according to the third configuration, the amplification suppression unit inputs a command signal output from the control unit to the drive supply unit and a start signal for starting the control unit, and these signals An arithmetic circuit that outputs a signal that is the logical product of the signals as a command signal to the drive supply means, and a path through which the activation signal is input to the arithmetic circuit, and a level change of the activation signal in the path is predetermined. And a delay circuit for delaying the period.

Further, as a configuration for suppressing the amplification action of the amplifier by the above-described amplification suppression means, for example, a fourth configuration shown below can be considered.
In the gap filler device according to a fourth configuration, the amplification suppression means includes a switch inserted in a path from the receiving antenna to the amplifier, and a predetermined period of time has elapsed after the gap filler device is activated. Until the time elapses, the path is opened by the switch.

According to the gap filler device according to the first configuration, the amplification action by the amplifier is suppressed until a predetermined period elapses after the device is started (including restart by reset, the same applies hereinafter). Therefore, immediately after the apparatus is started up, even if control for preventing the signal level of the broadcast signal from becoming excessively high due to an unstable operation state of the apparatus, until a predetermined period elapses. Can suppress the signal level of the broadcast signal that is retransmitted when the amplification action by the amplifier is suppressed. Thereby, it is possible to prevent the signal level of the retransmitted broadcast signal from becoming too high immediately after the gap filler device is started.

According to the gap filler device according to the second configuration, when the device main body is activated, the drive supply means that receives the command signal from the control unit supplies the drive signal to the amplifier, whereby the broadcast signal is supplied to the amplifier. Retransmission is performed in a state where the signal level is amplified, but the arrival of the command signal to the drive supply means is blocked until a predetermined period elapses after the control unit is activated. As a result, the amplification function by the amplifier does not function until the above period elapses, and the signal level of the broadcast signal is not amplified. As a result, the signal of the broadcast signal that is retransmitted immediately after the gap filler device is activated. It is possible to prevent the level from becoming too large.

According to the gap filler device of the third configuration, when the device main body is activated, the drive supply means that receives the command signal from the control unit supplies the drive signal to the amplifier, whereby the broadcast signal is supplied to the amplifier. Although the signal level is amplified again, the command signal to the drive supply means is a signal that is the logical product of the command signal from the control unit and the start signal for starting the control unit. Therefore, only when both signals are input to the arithmetic circuit, retransmission of the broadcast signal whose signal level is amplified is realized.

  The start signal to be input to the arithmetic circuit is delayed in the level change (change in signal level) by a delay circuit by a predetermined period, so that the apparatus main body is started and the start signal is supplied to the control unit. Even after the start, it is not input to the arithmetic circuit until the period elapses. This is because the drive signal is not supplied to the amplifier by the drive supply means by blocking the arrival of the command signal to the drive supply means until the predetermined period elapses after the apparatus main body is activated, This means that the amplifier does not amplify the signal level of the broadcast signal. Thereby, it can prevent that the signal level of the broadcast signal retransmitted until the predetermined period passes after starting the gap filler device becomes too high.

According to the gap filler device according to the fourth configuration, when the device main body is activated, the drive supply means that receives the command signal from the control unit supplies the drive signal to the amplifier, whereby the broadcast signal is supplied to the amplifier. Retransmission is performed in a state where the signal level is amplified, but the reception path from the reception antenna to the amplifier is opened by the switch until a predetermined period elapses after the control unit is activated. As a result, the signal level of the broadcast signal input to the amplifier can be suppressed to a level according to the insulation performance of the switch until the above period elapses. As a result, the amplification effect by the amplifier can be suppressed as compared with the case where the switch is not insulated, so that it is possible to prevent the signal level of the retransmitted broadcast signal from becoming too high immediately after the gap filler device is started.

Embodiments of the present invention will be described below with reference to the drawings.
(1) Overall configuration The gap filler device 1 receives a broadcast signal transmitted from the broadcasting station side by the receiving antenna 12, amplifies the signal level of the received broadcast signal by the amplifiers 14 and 16, and then transmits the signal. This is a device for retransmitting to the dead zone of radio waves by the trusted antenna 18.

  As shown in FIG. 1, the gap filler device 1 includes, in addition to the antennas 12 and 18 and the amplifiers 14 and 16, a CPU 22, a power switch 24, a reset circuit 26, a bias circuit 32, an arithmetic circuit 34, a delay circuit 36, and a path switch. 42, an attenuator 44, a directional coupler 46, a detector 48, and the like.

  Among these, the CPU 22 is configured to be activated by receiving an external activation signal and to control the overall operation of the gap filler device 1 in accordance with a predetermined procedure.

  The power switch 24 is a switch in which one contact is connected to the power source (+ B) and the other contact is connected to each component, and the two contacts are closed or opened in response to the operation of the operator. And it is comprised so that a starting signal (Vcc) may be supplied to each component by making the state between both contacts closed.

  The reset circuit 26 is activated by receiving an activation signal supplied from the outside, and has a command to wait for the operation of the CPU 22 only during a period assumed to be necessary for the signal level of the activation signal to be stabilized at an appropriate level. The reset signal (in this embodiment, an L level signal) is output to the CPU 22.

  In addition, the bias circuit 32 is operable by receiving an activation signal supplied from the outside, and in a situation where a command signal from the CPU 22 side (in this embodiment, an H level signal) is input. , 16 is supplied with a drive signal (bias voltage). Thus, the amplifiers 14 and 16 are in a state where the signal level of the broadcast signal received by the receiving antenna 12 can be amplified by receiving the drive signal.

  The arithmetic circuit 34 inputs a command signal (in this embodiment, an H level signal) output from the CPU 22 toward the bias circuit 32 and an activation signal supplied from the outside from each input terminal. An AND circuit that generates a logical product of these signals is output, and the signal thus generated is output as a command signal to the bias circuit 32 (in this embodiment, an H level signal).

  In the delay circuit 36, a period sufficiently longer than the period in which the reset circuit 26 outputs the reset signal is set as the delay period, and the start signal supplied from the outside to the arithmetic circuit 34 (that is, only during this delay period) , A known delay circuit configured to delay a change in the signal level in the activation signal). In the present embodiment, this delay period is a period during which the reset circuit 26 outputs a reset signal, and the input / output port (I / O port) is initialized after the CPU 22 is activated (the signal level is set to L level). ) Is set to be longer than the total period.

  The path switch 42 is inserted in the path from the receiving antenna 12 to the amplifier 14 in the previous stage, and opens the path in the initial state where no command signal is input from the CPU 22, whereas the path switch 42 receives a command from the CPU 22. The path is configured to be closed when a signal is input.

  The attenuator 44 is inserted in a path from the path switch 42 to the amplifier 14 in the previous stage, receives an instruction signal from the CPU 22, and a signal level attenuation in the path from the path switch 42 to the amplifier 14 in the previous stage. By changing (gain), the signal level of the broadcast signal flowing through the path is attenuated.

  The directional coupler 46 is inserted in a path from the subsequent stage amplifier 16 to the transmitting antenna 18 and is configured to branch a part of the broadcast signal in this path.

The detector 48 is configured to detect the average level of the signal components branched by the directional coupler 46 and notify the CPU 22 of the average level.
(2) Operation of Gap Filler Device 1 Hereinafter, the operation after the gap filler device 1 is started (including restart by reset, the same applies hereinafter) will be described.

  First, when both contacts of the power switch 24 are closed (see “Power ON” in FIG. 2), the CPU 22 is activated by receiving the activation signal, but also receives the activation signal. Since the reset signal from the reset circuit 26 activated in this way is input (see “Reset signal” in FIG. 2), the system waits until this input is completed.

  At this time, the CPU 22 issues a command to the bias circuit 32 via the input / output port due to the indefinite value of each register at the start-up and the unstable internal state during the start-up transition period. In some cases, a signal (a signal having a signal level of H level) may be output (see the shaded portion of “I / O port” in FIG. 2), but this command signal passes through an arithmetic circuit 34 that is an AND circuit. Is output. Therefore, even if the command signal from the CPU 22 is input from one input terminal in the arithmetic circuit 34, if the input signal (H level signal) is not input from the other input terminal, the command signal is at the H level. A signal is not output from the arithmetic circuit 34 to the bias circuit 32.

  Here, the signal input from the other input terminal of the arithmetic circuit 34 is an activation signal supplied via the power switch 24. This activation signal has its signal level changed only during the delay period described above. Since it is delayed by the delay circuit 36 (see “delay circuit output” in FIG. 2), the start signal is not input to the arithmetic circuit 34 within this period, so that a command signal is sent to the bias circuit 32. It is not output (refer to “arithmetic circuit output” in FIG. 2). In other words, the arithmetic circuit 34 and the delay circuit 36 function to block the command signal output from the CPU 22 from reaching the bias circuit 32 until the delay period elapses.

  Further, when the gap filler device 1 is activated, the path from the receiving antenna 12 to the amplifier 14 at the previous stage is opened by the path switch 42, so that even if a broadcast signal is received by the receiving antenna 12. In response to the isolation of the path switch 42, the signal level of the broadcast signal input to the amplifier 14 is attenuated.

  Thereafter, when the reset circuit 26 finishes outputting the reset signal to the CPU 22 (see “Reset Period End” in FIG. 2), the CPU 22 starts outputting the command signal to the path switch 42 and the arithmetic circuit 34.

  Thus, as described above, even when the normal command signal from the CPU 22 is input from one input terminal, the arithmetic circuit 34 receives the activation signal delayed by the delay circuit 36 from the other input terminal. If not input, the command signal is not output to the bias circuit 32. However, when the delay period by the delay circuit 36 elapses, both the command signal and the start signal from the CPU 22 are input to the arithmetic circuit 34. As a result, the command signal from the arithmetic circuit 34 is output to the bias circuit 32 (see “bias ON” in FIG. 2).

  The bias circuit 32 that has received the command signal from the arithmetic circuit 34 supplies a drive signal to the amplifiers 14 and 16 while the command signal is being input. As a result, the signal level of the broadcast signal received by the receiving antenna 12 is amplified by the amplifiers 14 and 16.

  Further, the path switch 42 keeps the path from the receiving antenna 12 to the preceding amplifier 14 closed while the command signal from the CPU 22 is being input. As a result, the broadcast signal received by the receiving antenna 12 is input to the amplifier 14 without the signal level being attenuated by the path switch 42 (excluding the influence of resistance due to energization of the path switch 42). .

Then, after starting the output of the command signal to the arithmetic circuit 34, the CPU 22 outputs the command signal to the attenuator 44 so that the average level of the broadcast signal detected by the detector 48 does not exceed a predetermined signal level. Then, the attenuation degree is feedback-controlled.
(3) Operation and Effect According to the gap filler device 1 configured as described above, when the device main body is activated, the bias circuit 32 that receives a command signal from the CPU 22 supplies a drive signal to the amplifiers 14 and 16. As a result, the broadcast signal is retransmitted to the amplifiers 14 and 16 with the signal level amplified. The command signal to the bias circuit 32 is the command signal from the CPU 22 and the start signal. Since the signal is a logical product, retransmission of the broadcast signal whose signal level is amplified is realized only when both signals are input to the arithmetic circuit 34.

  The activation signal to be input to the arithmetic circuit 34 is delayed in the signal level by the delay circuit 36 by a delay period. Therefore, after the apparatus main body is activated and the supply of the activation signal to the CPU 22 is started. However, it is not input to the arithmetic circuit 34 until the period elapses. This is because the arrival of the command signal to the bias circuit 32 is interrupted at least until the delay period elapses after the apparatus main body is activated, so that the drive signal to the amplifiers 14 and 16 by the bias circuit 32 is blocked. This means that the signal level of the broadcast signal is not amplified by the amplifiers 14 and 16 without being supplied.

  For this reason, immediately after the device is started, the CPU 22 causes the bias circuit 32 side (that is, the arithmetic circuit) because the value of each register at the time of startup is unstable or the internal state is unstable during the startup transition period. 34) Even if the command signal is output to 34), the signal level of the broadcast signal to be retransmitted is suppressed as a result of the amplifier 14 and 16 not amplifying the signal level until the delay period by the delay circuit 36 elapses. Can do. Thereby, it is possible to prevent the signal level of the retransmitted broadcast signal from becoming too high immediately after the gap filler device 1 is started.

The path switch 42 provided in the path from the receiving antenna 12 to the attenuator 44 opens the path in the initial state where no command signal is input from the CPU 22, and after the gap filler device 1 is started, When the input of the reset signal to the CPU 22 is completed, the route is closed by receiving a command signal from the CPU 22. That is, the path is open at least after the gap filler device 1 is activated until the delay period elapses. Thus, the broadcast signal input to the amplifier 14 in the previous stage can be suppressed to a level corresponding to the insulation performance of the path switch 42 until the delay period elapses after the apparatus main body is activated.
(4) Modifications The embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment, and can take various forms as long as they belong to the technical scope of the present invention. Needless to say.

  For example, in the above embodiment, the configuration in which the arithmetic circuit 34 is composed of an AND circuit is exemplified, but the arithmetic circuit 34 is connected to the command signal output from the CPU 22 toward the bias circuit 32 and the power switch 24. A circuit configuration other than the AND circuit may be used as long as a signal that is a logical product of the supplied activation signals can be generated.

  In the above embodiment, the arithmetic circuit 34 and the delay circuit 36 are configured to block the arrival of the command signal to the bias circuit 32 until the delay period elapses after the apparatus main body is activated. did. However, the configuration for blocking the arrival of the command signal to the bias circuit 32 until the delay period elapses may be realized by another circuit configuration.

  In the above embodiment, the operation circuit 34 and the delay circuit 36 block the arrival of the command signal to the bias circuit 32, and the path is opened by the path switch 42, so that the gap filler device 1 is immediately started. 1 illustrates an example of a configuration in which the signal level of a retransmitted broadcast signal is prevented from becoming excessively high. However, such a configuration that prevents the signal level of the retransmitted broadcast signal from becoming too high can be realized only by the path switch 42. In this case, since the signal level of the broadcast signal input to the amplifier 14 can be suppressed to a level according to the insulation performance of the path switch 42 until the delay period elapses, the amplification action by the amplifiers 14 and 16 functions. Even if it is, the amplification effect by the amplifiers 14 and 16 can be suppressed as compared with the case where the path switch 42 does not insulate. As a result, the signal level of the retransmitted broadcast signal is increased immediately after the gap filler device 1 is activated. It can prevent becoming too much.

In the above embodiment, a frequency converter may be used in the path from the attenuator 44 to the transmitting antenna 18. In this case, the local oscillator signal from the frequency converter is stable until it becomes stable. The path may be opened by the switch 42, or the signal level may be attenuated by the attenuator 44.
(5) Correspondence with the Present Invention In the embodiment described above, the arithmetic circuit 34, the delay circuit 36, and the path switch 42 are amplification suppression means in the present invention, and the bias circuit 32 is a drive supply means in the present invention. is there. The delay time by the delay circuit 36 corresponds to the predetermined period in the present invention.

The block diagram which shows the structure of the gap filler apparatus 1 The figure which shows the waveform of the signal which flows through each part

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Gap filler apparatus, 12 ... Reception antenna, 14 ... Amplifier, 16 ... Amplifier, 18 ... Transmission antenna, 24 ... Power switch, 26 ... Reset circuit, 32 ... Bias circuit, 34 ... Operation circuit, 36 ... Delay circuit , 42 ... path switch, 44 ... attenuator, 46 ... directional coupler, 48 ... detector.

Claims (2)

A gap filler device that receives a broadcast signal transmitted from a broadcast station side by a receiving antenna, retransmits the received broadcast signal by an amplifier for transmission after amplifying a signal level by an amplifier,
Amplification suppression means for suppressing the amplification action by the amplifier on the broadcast signal until the predetermined period has elapsed since the gap filler device was activated ,
Drive supply means for receiving a command signal from a control unit for controlling the operation of the entire gap filler device and starting supply of the drive signal for driving the amplifier to the amplifier,
The amplification suppression unit is configured to block the arrival of a command signal from the control unit to the drive supply unit until a predetermined period elapses after the control unit is activated,
further,
The amplification suppression means is
A command signal output from the control unit to the drive supply unit and a start signal for starting the control unit are input, and a signal that is a logical product of these signals is used as a command signal to the drive supply unit. An arithmetic circuit to output,
A gap filler device comprising: a delay circuit that is inserted into a path through which the activation signal is input to the arithmetic circuit and delays a level change of the activation signal in the path by a predetermined period . The amplification suppression means has a switch inserted in a path from the receiving antenna to the amplifier, and the switch uses the switch to start the path from the start of the gap filler device until a predetermined period elapses. It is comprised so that it may open | release. The gap filler apparatus of Claim 1 characterized by the above-mentioned.

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