JP5617106B2 - booster - Google Patents

Description

  The present invention relates to a booster, and more particularly, to a booster provided with upstream signal amplification means for amplifying an upstream signal.

  In a bidirectional transmission system including a center station and a plurality of subscriber terminal devices and having a transmission function for downlink signals and uplink signals, a bidirectional booster is usually provided. Here, FIG. 4 shows an example of a conventional configuration of a bidirectional booster installed in an apartment house on the subscriber side.

  The conventional bidirectional booster shown in FIG. 4 is a booster capable of amplifying an upstream signal in a frequency band of 10 to 60 MHz and amplifying a downstream signal in a frequency band of 70 to 770 MHz.

  The conventional bidirectional booster shown in FIG. 4 includes a downstream signal input / upstream signal output terminal T1, a 770 MHz LPF (Low Pass Filter) 1 that passes a frequency band of 770 MHz or lower, and a 70 MHz HPF (High Pass) that passes a frequency band of 70 MHz or higher. Filter) 2, branching device 3, attenuator / equalizer unit 4 that performs gain attenuation and frequency characteristic change, branching device 5, downstream signal amplifier 6 that amplifies the downstream signal, gain control circuit 7, downstream signal amplifier 8, tilt circuit 9 for adjusting tilt characteristics, downstream signal amplifier 10, 70 MHz HPF 11, 770 MHz LPF 12, branching device 13, downstream signal output / upstream signal input terminal T2, downstream signal output monitor / upstream signal adjustment And an input terminal T3.

  The conventional bidirectional booster shown in FIG. 4 further includes a 60 MHz LPF 14 that passes a frequency band of 60 MHz or less, a 10 MHz HPF 15 that passes a frequency band of 10 MHz or more, a branching device 16, an upstream signal amplifier 17 that amplifies an upstream signal, A tilt circuit 18, a gain control circuit 19, an upstream signal amplifier 20, an attenuator 21 that performs gain attenuation, a branching device 22, a 10 MHz HPF 23, a 60 MHz LPF 24, and an upstream signal output monitor terminal T4 are provided.

  The conventional bidirectional booster shown in FIG. 4 also includes a downstream signal input monitor terminal T5, an internal monitor terminal T6, and an upstream signal input monitor terminal T7.

  The downlink signal transmitted from the center station is input to the downlink signal input / uplink signal output terminal T1, passes through the 770 MHz LPF1 and 70 MHz HPF2, passes through the branching device 3, and is changed in gain attenuation and frequency characteristics by the attenuator / equalizer unit 4. Then, the signal is amplified by the downstream signal amplifier 6 via the branching unit 5, adjusted in gain by the gain control circuit 7, amplified by the downstream signal amplifier 8, adjusted in tilt characteristics by the tilt circuit 9, and amplified by the downstream signal amplifier 10. Then, the signal passes through the 70 MHz HPF 11 and the 770 MHz LPF 12, and is output from the downlink signal output / uplink signal input terminal T2 via the branching device 13. Then, the branch output of the branching device 3 is supplied to the downstream signal input monitor terminal T5, the branch output of the branching device 5 is supplied to the internal monitor terminal T6, and the branch output of the branching device 13 is used for the downstream signal output monitoring and upstream signal adjustment. It is supplied to the input terminal T3.

  On the other hand, the upstream signal transmitted from the subscriber terminal device is input to the downstream signal output / upstream signal input terminal T2, passes through the branching device 13 and passes through the 770 MHz LPF 12, 60 MHz LPF 14, and 10 MHz HPF 15, and passes through the branching device 16. The signal is amplified by the upstream signal amplifier 17, the tilt characteristic is adjusted by the tilt circuit 18, the gain is adjusted by the gain control circuit 19, amplified by the upstream signal amplifier 20, and the gain is attenuated by the attenuator 21. Then, the signal passes through the 10 MHz HPF 23, the 60 MHz LPF 24, and the 770 MHz LPF 1 and is output from the downstream signal input / upstream signal output terminal T1. The branch output of the branching device 16 is supplied to the upstream signal input monitor terminal T7, and the branch output of the branching device 22 is supplied to the upstream signal output monitor terminal T4.

JP 2003-111043 A (paragraph 0003)

  In the conventional bidirectional booster shown in FIG. 4, a switch for turning on / off the function of the attenuator / equalizer unit 4, a volume for determining the gain adjustment amount of the gain control circuit 7, and a function of the tilt circuit 9 are turned on. A switch for turning off / off is provided, and a downstream signal is adjusted using these switches. The attenuator / equalizer unit 4 is a through circuit if the function is off. Similarly, the tilt circuit 9 becomes a through circuit if the function is off.

  In the conventional bidirectional booster shown in FIG. 4, a switch for turning on / off the function of the tilt circuit 18, a volume for determining a gain adjustment amount of the gain control circuit 19, and a function of the attenuator 21 are turned on / off. Are provided for adjusting the upstream signal. The tilt circuit 18 is a through circuit if the function is off. Similarly, the attenuator 21 becomes a through circuit if the function is off.

  In the adjustment of the upstream signal, the downstream signal input / upstream signal output terminal T1 and the downstream signal output / upstream signal input terminal T2 are connected to the downstream signal output monitor / upstream signal adjustment input terminal T3 in the state where the coaxial cable is connected. A test signal for signal adjustment (a signal having an upstream bandwidth of 10 to 60 MHz) is input, and a signal (upstream signal output monitor signal) output from the upstream signal output monitor terminal T4 is measured to measure inflow noise. During this upstream signal adjustment, the amplified test signal is output from the downstream signal input / upstream signal output terminal T1, and inflow noise flows from the downstream signal input / upstream signal output terminal T1 to the center station, affecting the center station. I gave it.

  Note that the above problem is not limited to the bidirectional booster, but may also occur in a booster that includes upstream signal amplification means that amplifies upstream signals but does not include downstream signal amplification means that amplifies downstream signals.

  Further, the booster disclosed in Patent Document 1 includes a plurality of terminals (a plurality of uplink signal input terminals) for supplying an uplink signal from each terminal to an uplink signal amplifying means for amplifying the uplink signal. This is a bidirectional booster that does not have an output monitor terminal. In turn, turn on and off the gate switches that turn on and off the upstream signals supplied from various lines to the bidirectional booster, and investigate in which line the noise that has a large effect on the inflow noise occurs. doing. For this reason, at the time of the investigation, the center station was affected during the period when the gate switch of the line where the noise that greatly affects the inflow noise was generated was on.

  In view of the above situation, an object of the present invention is to provide a booster capable of adjusting an uplink signal without affecting a center station.

  In order to achieve the above object, a booster according to the present invention comprises an upstream signal amplifying means for amplifying an upstream signal or a test signal for upstream signal adjustment, an upstream signal output terminal, the upstream signal amplifying means, and the upstream signal output terminal. A first state in which the upstream signal amplifying means and the upstream signal output terminal are electrically connected, and the upstream signal amplifying means and the upstream signal output terminal are electrically connected to each other. Switch means for switching a second state not connected to each other, a branch means provided between the upstream signal amplification means and the switch means, and an upstream signal output monitor terminal to which a branch output of the branch means is supplied It is set as the structure provided with.

  In the booster having the above-described configuration, the switch means selects the second state when adjusting the up signal, and the switch means selects the first state during normal use after adjusting the up signal. Thereby, at the time of upstream signal adjustment, transmission of the test signal amplified by the upstream signal amplification means is cut by the switch means, so that the amplified test signal is not output from the upstream signal output terminal, and the upstream signal Infusion noise does not flow from the output terminal to the center station. Therefore, the center station is not affected. In addition, as a result, during normal use after the adjustment of the upstream signal, the upstream signal amplified by the upstream signal amplifying means is output from the upstream signal output terminal without any problem via the switch means, as in the conventional case. Are transmitted from the upstream signal output terminal to the center station.

  At the time of upstream signal adjustment, even if the switch means selects the second state, the test signal amplified by the upstream signal amplification means is output from the upstream signal output monitor terminal. It is possible to measure the inflow noise by measuring the signal (upstream signal output monitor signal) output from the upstream signal output monitor terminal.

  In addition, when switching from upstream signal adjustment to normal use, the switch means is configured to reduce the forgetting to switch the selection destination of the switch means (forgetting to switch from the second state to the first state). It is preferable to provide notifying means for notifying that when the second state is selected.

  Furthermore, from the viewpoint of facilitating the distinction between the notification by the notification unit and the pilot display that generally indicates that the pilot state is displayed by lighting a light emitting diode or the like, the notification unit includes the light emission unit and the light emission unit. It is more preferable that when the switch means selects the second state, the fact that the light emission means blinks is provided.

  A first diode provided on a transmission line between the branching unit and the switch unit; a second diode having a cathode commonly connected to a cathode of the first diode; and the second diode. And when the switch means selects the first state, the anode voltage of the first diode is larger than the anode voltage of the second diode. When the first diode is on, the second diode is off, and the switch means selects the second state, the anode voltage of the first diode is the second diode. The first diode may be turned off and the second diode may be turned on by making the voltage lower than the anode voltage. . Thereby, when the switch means selects the second state, the transmission line on the branch means side is terminated by the terminator. In addition, when the switch means selects the second state, the transmission line on the upstream signal output terminal side is terminated by a terminator different from the terminator. By installing such a terminator, it is possible to maintain a good VSWR (Voltage Standing Wave Ratio) even when the switch means selects the second state.

  According to the present invention, it is possible to realize a booster capable of adjusting an uplink signal without affecting the center station.

It is a figure which shows the structure of the bidirectional | two-way booster which concerns on one Embodiment of this invention. It is a figure which shows the example of 1 structure of a cut switch part. It is a figure which shows the structure of the booster which concerns on other embodiment of this invention. It is a figure which shows the example of a conventional structure of a bidirectional | two-way booster.

  Embodiments of the present invention will be described below with reference to the drawings. The structure of the bidirectional | two-way booster which concerns on one Embodiment of this invention is shown in FIG. In FIG. 1, the same parts as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The bidirectional booster according to an embodiment of the present invention shown in FIG. 1 has a configuration in which a cut switch unit 25 is added to the conventional bidirectional booster shown in FIG. The cut switch unit 25 is provided between the branching device 22 and the 10 MHz HPF 23.

  Next, a configuration example of the cut switch unit 25 is shown in FIG. The cut switch unit 25 of the configuration example shown in FIG. 2 includes a double-pole double-throw switch SW1, capacitors C1 to C7, diodes D1 and D2, a light emitting diode D3, coils M1 to M3, NPN transistors Q1 to Q3, Resistors R1 to R14. As the double-pole double-throw switch SW1, for example, a slide switch that manually slides to selectively select two connection destinations can be used.

  One pole of the double-pole double-throw switch SW1 is connected to one end of the coil M1 and one end of a DC blocking capacitor C7. The other end of the capacitor C7 is connected to a 10 MHz HPF 23 (see FIG. 1). The other pole of double-pole double-throw switch SW1 is connected to the anode of diode D1 and one end of coil M2.

  The other end of the coil M2 is connected to one end of the resistor R1, and the other end of the resistor R1 is connected to the contact a1 and the contact a2 of the double-pole double-throw switch SW1. The contact a1 and contact a2 of the double pole double throw switch SW1 are short-circuited.

  The cathode of the diode D1 and the cathode of the diode D2 are connected in common, and are connected to one end of the resistor R14 and one end of the DC blocking capacitor C6. The other end of the resistor R14 is connected to the ground potential. The other end of the capacitor C6 is connected to the branching device 22 (see FIG. 1). The anode of the diode D2 is connected to the emitter of the NPN transistor Q1 and one end of the capacitor C1 through the resistor R2. The other end of the capacitor C1 is connected to the ground potential.

Further, a DC voltage _VDC having a predetermined value (for example, 24 V) is applied to the other end of the coil M1, one end of the resistor R3, and the collector of the NPN transistor Q1. The other end of resistor R3 is connected to the base of NPN transistor Q1 and one end of resistor R4. The other end of the resistor R4 is connected to the ground potential.

  The contact b1 of the double-pole double-throw switch SW1 is open. On the other hand, the contact b2 of the double-pole double-throw switch SW1 is connected to one end of the capacitor C2 and one end of the coil M3. The other end of the capacitor C2 is connected to one end of the resistor R5, and the other end of the resistor R5 is connected to the ground potential.

  The other end of the coil M3 is connected to one end of the capacitor C3 and one end of the resistor R6. The other end of the resistor R6 is connected to one end of the resistor R7, one end of the resistors R8 to R10, and the anode of the light emitting diode D3. The other end of the capacitor C3 and the other end of the resistor R7 are connected to the ground potential.

  The other end of resistor R8 is connected to the collector of NPN transistor Q2 and one end of capacitor C4. The cathode of the light emitting diode D3 is connected to the collector of the NPN transistor Q3 and one end of the capacitor C5 through the resistor R11.

  The other end of resistor R9 is connected to the other end of capacitor C4 and the base of NPN transistor Q3 via resistor R12. The other end of the resistor R10 is connected to the other end of the capacitor C5 and the base of the NPN transistor Q2 via the resistor R13. The emitter of NPN transistor Q2 and the emitter of NPN transistor Q3 are connected to the ground potential.

The light emitting diode blinking circuit 26 is an astable multivibrator configured by the light emitting diode D3, capacitors C3 to C5, resistors R6 to R13, and NPN transistors Q2 and Q3. The light-emitting diode blinking circuit 26 is activated when a predetermined value of the DC voltage _VDC is applied to the connection point between the resistor R6 and the capacitor C3, and the NPN transistor Q2 and the NPN transistor Q3 are alternately turned on and off. The light emitting diode D3 is turned on repeatedly when the NPN transistor Q3 is turned on, and the light emitting diode D3 is turned off when the NPN transistor Q3 is turned off.

  The cut switch unit 25 having the above configuration (configuration example shown in FIG. 2) operates as follows.

Voltage dividing by the resistance R3 and R4 of the DC voltage _{V DC} of the predetermined value is supplied to the base of constantly NPN transistor Q1, the NPN transistor Q1 is always in the ON state, the NPN transistor Q1 from the DC voltage _{V DC} of the predetermined value A DC voltage stepped down by the collector-emitter voltage is always supplied to the anode of the diode D2.

When the double-pole double-throw switch SW1 selects the contacts a1 and a2 side, the DC voltage _VDC of a predetermined value applied to the other end of the coil M1 is one pole of the double-pole double-throw switch SW1, double-pole double-throw switch The voltage is supplied to the anode of the diode D1 via the contact point a2, the resistor R1, and the coil M2, and the diode D1 is turned on. The high-frequency signal transmitted from the branching device 22 (see FIG. 1) includes the capacitor C6, the diode D1 in the on state, the other pole of the double-pole double-throw switch SW1, the contact a1 of the double-pole double-throw switch SW1, and the contact a1. Is transmitted to the 10 MHz HPF 23 (see FIG. 1) via the short-circuit line connecting the contact point a2 and the contact point a2 of the double-pole double-throw switch SW1, one pole of the double-pole double-throw switch SW1, and the capacitor C7.

  Further, when the double-pole double-throw switch SW1 selects the contacts a1 and a2 side, the cathode voltage of the diode D1 and the cathode voltage of the diode D2 are the same, and the diode D1 is on as described above, and the diode D2 Since the anode voltage is smaller than the anode voltage of the diode D1 by the collector-emitter voltage of the NPN transistor Q1, the diode D2 is turned off.

When the double-pole double-throw switch SW1 selects the contacts a1 and a2 side, the DC voltage _VDC having a predetermined value is not supplied to the contact b2 of the double-pole double-throw switch SW1, so that the LED blinking circuit 26 has a predetermined value. The direct current voltage _VDC is not supplied, and the light emitting diode blinking circuit 26 does not operate. Therefore, the light emitting diode D3 is turned off.

On the other hand, when the double-pole double-throw switch SW1 selects the contacts b1 and b2 side, since the DC voltage _VDC having a predetermined value is not supplied to the anode of the diode D1, the diode D1 is turned off. In addition, one pole and the other pole of the double pole double throw switch SW1 are electrically cut off. Therefore, the high frequency signal transmitted from the branching device 22 (see FIG. 1) is not transmitted to the 10 MHz HPF 23 (see FIG. 1).

When the double-pole double-throw switch SW1 selects the contacts b1 and b2 side, the cathode voltage of the diode D1 and the cathode voltage of the diode D2 are the same, but the diode D1 is in the OFF state as described above, and the predetermined value Since the direct-current voltage obtained by stepping down the direct-current voltage _{VDC by} the collector-emitter voltage of the NPN transistor Q1 is supplied to the anode of the diode D2, the diode D2 is turned on. Thus, the transmission line connected to the branching device 22 (see FIG. 1) is terminated by 75Ω by the capacitor C1, the NPN transistor Q1, and the resistors R2 to R4.

Further, when the double-pole double-throw switch SW1 selects the contacts b1 and b2 side, one pole of the double-pole double-throw switch SW1 and the contact b2 are connected. As a result, the transmission line connected to the 10 MHz HPF 23 (see FIG. 1) is terminated by 75Ω by the capacitor C2 and the resistor R5. This also causes a predetermined value of the DC voltage _VDC applied to the other end of the coil M1 to emit light via one pole of the double-pole double-throw switch SW1, the contact b2 of the double-pole double-throw switch SW1, and the coil M3. The light is supplied to the diode flashing circuit 26, and the light emitting diode flashing circuit 26 operates. Therefore, the light emitting diode D3 is in a blinking state.

  In consideration of the above operation, the double-pole double-throw switch SW1 selects the contacts b1 and b2 side during the up signal adjustment, and the double-pole double-throw switch SW1 selects the contacts a1 and a2 side during normal use after the up signal adjustment. To.

  Thereby, at the time of upstream signal adjustment, transmission of the amplified test signal is cut by the cut switch unit 25, so that the amplified test signal is not output from the downstream signal input / upstream signal output terminal T1, and the downstream signal input / portion is also output. Inflow noise does not flow out from the upstream signal output terminal T1 to the center station. Therefore, the center station is not affected. Further, when the upstream signal is adjusted, the light emitting diode D3 blinks, so that the user can confirm that the transmission of the signal from the branching device 22 (see FIG. 1) to the 10 MHz HPF 23 (see FIG. 1) is cut by the cut switch unit 25. Since the notification is made, it is possible to reduce forgetting to switch the selection destination of the double-pole double-throw switch SW1 when switching from upstream signal adjustment to normal use. The test signal for upstream signal adjustment is input to the downstream signal output monitor / upstream signal adjustment input terminal T3 and is adjusted by the tilt circuit 18, the gain control circuit 19, and the attenuator 21 as in the prior art. 22 is branched and output from the upstream signal output monitor terminal T4. Then, based on the measurement result of the signal output from the upstream signal output monitor terminal T4 (upstream signal output monitor signal) so that the upstream signal becomes an appropriate level, the tilt circuit 18, the gain control circuit 19, and the attenuator 21 Each setting is determined.

  In addition, as a result, during normal use after adjusting the uplink signal, the high-frequency signal transmitted from the branching device 22 (see FIG. 1) is transmitted to the 10 MHz HPF 23 (see FIG. 1) via the cut switch unit 25. Therefore, the bidirectional booster according to the embodiment of the present invention shown in FIG. 1 is equivalent to the conventional bidirectional booster shown in FIG.

  As mentioned above, although embodiment which concerns on this invention was described, the range of this invention is not limited to this, A various change can be added and implemented in the range which does not deviate from the main point of invention.

  For example, in the above-described embodiment, the user is notified that the signal transmission from the branching device 22 (see FIG. 1) to the 10 MHz HPF 23 (see FIG. 1) is cut by the cut switch unit 25 by blinking the light emitting diode D3. However, it is also possible to employ a notification method such as turning on a light emitting diode, outputting a specific sound, or the like. However, since the lighting of the light emitting diode is often used as a pilot display, when the notification using the light emitting diode is adopted, the notification by blinking the light emitting diode as in the present embodiment is performed and the pilot display can be easily performed. It is preferable to be able to distinguish.

  Further, for example, a booster that does not handle downstream signals as shown in FIG. 3 may be used. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. The booster according to another embodiment of the present invention shown in FIG. 3 includes a 770 MHz LPF1, a 70 MHz HPF2, a branching device 3, an attenuator / equalizer unit 4 from the bidirectional booster according to the embodiment of the present invention shown in FIG. The branching unit 5, the downstream signal amplifier 6, the gain control circuit 7, the downstream signal amplifier 8, the tilt circuit 9, the downstream signal amplifier 10, the 70 MHz HPF 11, and the 770 MHz LPF 12 are excluded. In addition, since the booster according to another embodiment of the present invention shown in FIG. 3 does not handle the downstream signal, the terminal T1 is not the downstream signal input / upstream signal output terminal but the upstream signal output terminal, and the terminal T2 is the downstream signal output. The upstream signal input terminal is not an upstream signal input terminal, and the terminal T3 is not a downstream signal output monitor / upstream signal adjustment input terminal but an upstream signal adjustment input terminal.

  In the above-described embodiment, the 10 MHz HPF and the 60 MHz LPF are used as filters that allow the upstream signal to pass. However, a 10 to 60 MHz BPF (Band Pass Filter) may be used instead.

  In the above-described embodiment, the downstream signal is a signal in the frequency band of 70 to 770 MHz (CATV signal), but the signal in the frequency band of 470 to 770 MHz (terrestrial digital broadcast signal in the UHF band) or 950 to 2610 MHz. A bidirectional booster that uses a frequency band signal (BS / CS-IF band satellite broadcast signal) as a downstream signal may be used.

1,12 770MHz LPF
2, 11 70 MHz HPF
3, 5, 13, 16, 22 Branch device 4 Attenuator / Equalizer section 6, 8, 10 Downstream signal amplifier 7, 19 Gain control circuit 9, 18 Tilt circuit 14, 24 60 MHz LPF
15, 23 10MHz HPF
17, 20 Up signal amplifier 21 Attenuator 25 Cut switch unit 26 Light emitting diode blinking circuit C1 to C7 Capacitor D1, D2 Diode D3 Light emitting diode M1 to M3 Coil Q1 to Q3 NPN transistor R1 to R14 Resistance SW1 Double pole double throw switch T1 Downstream signal input Upstream signal output terminal T2 Downstream signal output / upstream signal input terminal T3 Downstream signal output monitor / upstream signal adjustment input terminal T4 Upstream signal output monitor terminal T5 Downstream signal input monitor terminal T6 Internal monitor terminal T7 Upstream signal input monitor terminal

Claims (3)

An upstream signal amplifying means for amplifying an upstream signal or a test signal for upstream signal adjustment;
An upstream signal output terminal;
A first state provided on a transmission line between the upstream signal amplifying means and the upstream signal output terminal, wherein the upstream signal amplifying means and the upstream signal output terminal are electrically connected; and the upstream signal Switch means for switching a second state in which the amplification means and the upstream signal output terminal are not electrically connected;
Branching means provided between the upstream signal amplifying means and the switch means;
An upstream signal output monitor terminal to which the branch output of the branch means is supplied ;
A first diode provided on a transmission line between the branching means and the switch means;
A second diode having a cathode commonly connected to the cathode of the first diode;
A terminator connected to the anode of the second diode;
When the switch means selects the first state, the anode voltage of the first diode becomes larger than the anode voltage of the second diode, so that the first diode is turned on, and the second diode The diode of is turned off,
When the switch means selects the second state, the anode voltage of the first diode becomes smaller than the anode voltage of the second diode, so that the first diode is turned off, and the second state The booster is characterized in that the diode of is turned on .   2. The booster according to claim 1, further comprising notification means for notifying that when the switch means is selecting the second state.   The notifying means includes a light emitting means and a driving means for driving the light emitting means, and when the switch means selects the second state, the fact is notified by blinking of the light emitting means. The booster according to claim 2.

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