JP4664701B2 - Television receiving amplifying device and television receiving system - Google Patents

Description

The present invention relates to a television receiving amplifying apparatus mainly used for receiving a television broadcast, and more specifically, an amplifying apparatus mainly used for a mobile body and receiving terrestrial digital broadcasting, and a receiving system using the same. About.

Conventionally, a television receiving amplifying device is used by being attached in the vicinity of an antenna for television broadcasting, and a television receiving amplifier is attached in the vicinity of a terminal side device such as a television or a VTR. Since the former is mounted in the vicinity of the antenna, it is impossible for one builder to perform gain adjustment, attenuator, etc. while watching TV images, and the work efficiency is extremely poor.
On the other hand, in the latter case, the input level to the amplifying device is lowered and C / N may be deteriorated due to transmission loss of the coaxial cable interposed between the antenna and the amplifying device. Therefore, in order to solve such a problem, a device in which an amplification device is divided into a first amplification unit installed in the vicinity of the antenna and a second amplification unit installed in the vicinity of the terminal side device has been proposed. The signal received by the television antenna is input to the first amplifying unit via the coaxial cable. The input signal is output from the first amplifying unit after passing through the power source separation filter after the first amplifier or attenuator is selected by the relay as the switching means. This selection is performed by turning on and off the switch provided in the second amplifying unit, so that the power supply separation filter of the second amplifying unit, the coaxial cable, and the power supply separation of the first amplifying unit are separated from the power supply provided in the second amplifying unit. The power is turned on and off to the relay through the filter, and the relay is switched by this.
Furthermore, an optimum power source is also supplied from the power source provided in the second amplifying unit to the first amplifier and the second amplifier provided in the second amplifying unit. The reception signal amplified in the first amplifying unit in this way is input to the second amplifying unit via a coaxial cable. This input signal passes through the power supply separation filter, is appropriately gain-adjusted by the variable attenuator, is amplified by the second amplifier, is output from the second amplifier, and is supplied to the television receiver 23.
Therefore, in this embodiment, not only can the gain be adjusted while watching the television receiver, but also the dynamic range of the amplifying device can be expanded by operating the switch. An amplifying device is provided.
(For example, see Patent Document 1)

JP-A-6-326534

However, according to the conventional TV receiving amplifying apparatus, for example, considering receiving terrestrial digital broadcasting started in the UHF band, until the digital broadcasting in 2011 is completely digitalized, Will be the simulcast. For this reason, the transmission power of terrestrial digital broadcast waves is gradually increased in order to prevent the number of UHF band channels from increasing and the influence of analog reception and digital reception from affecting each other. The reception status changes. As a result, a multi-channel signal is input to the TV receiving amplifying device or the input level becomes higher than before, and an excessive level input signal is input to the amplifying device. Will be distorted and disturb the video.

By the way, terrestrial digital broadcasting can receive services such as data broadcasting as well as high-quality and high-quality broadcasting. As one of its usage methods, for example, in a mobile vehicle such as a private car or taxi, You can enjoy broadcasting. In such a case, a digital terrestrial antenna is installed on the roof of the car, and a terminal device such as a terrestrial digital broadcast tuner is installed in the car or in the trunk room. A receiving system such as that seen on an installed LCD TV is conceivable. In this system, the coaxial cable from the antenna needs to be drawn into the car, so the transmission line interposed between the TV antenna and the terminal side device must be flexible so that it can be routed in line with the body line. A small-diameter coaxial cable is suitable so that it can be easily pulled into the vehicle. However, a thin coaxial cable generally has a larger transmission loss than a coaxial cable equivalent to 5C used in a home joint reception system, and its value increases as the frequency band used increases. The signal level input to the digital terrestrial broadcasting tuner (for example, a terrestrial digital broadcast tuner) is lowered, thereby deteriorating the C / N characteristics of reception.

In view of this, a method for stably receiving television by interposing an amplifying device for TV reception between the antenna and the terminal side device is conceivable. To maintain a good C / N, the amplifying device is connected to the antenna. It is necessary to install it in the power feeding section or install it in the vicinity of the antenna. However, if an amplifier with high amplification is arranged near the antenna, there is a problem that oscillation may occur, or even if the problem of transmission is improved, the configuration of the amplifier circuit is required to increase the amplification. Increasing the number of parts and the structure of the case to improve shielding performance, resulting in an increase in the outer shape of the amplifying device, resulting in increased costs, as well as vehicle roofs, etc. There was a problem that it would be difficult to install.

Further, as in the conventional example, the amplifying device is configured by a first amplifying unit and a second amplifying unit, and the first amplifying unit and the first amplifying unit are connected by a coaxial cable. For example, a TV reception amplifying device with little deterioration of C / N can be made. However, in the circuit configuration as shown in the conventional example, the transmission power of the terrestrial digital broadcast wave is not full power or stable. Even if it is installed in an optimal state so that it can be used in an area that is not released, the full-digitalization after 2011 in terrestrial broadcasting will increase the number of channels and increase the transmission power. It is conceivable that an excessive input is input and the input of the amplifier is over. In addition, considering that the electric field strength may change greatly in a short time when used in a mobile object such as a car, the second amplifying unit is used to cope with these input changes. Corresponding to changes in the input level by operating the provided switch has a problem that it is impossible to respond instantaneously when moving (ie during operation). Further, in order to enable operation, there is a problem that the installation location of the second amplification unit is extremely limited in order to make the switch operation cheap.
Therefore, the present invention has been made to solve such problems,
The purpose is to provide an amplifying apparatus for television reception.
Another object of the present invention is to provide a television receiving amplifying apparatus having a wide input level dynamic range.
Another object is to provide an amplifying apparatus for television reception including a first amplifying section, a second amplifying section, and a terminal side apparatus.
Another object is to provide an amplifying apparatus for television reception suitable for in-vehicle use.
Another object is to provide an amplifying apparatus for receiving television for enjoying terrestrial digital broadcasting on a mobile object.

In order to solve the above problems, the invention of claim 1 amplifies television signals received by a plurality of antennas for receiving television broadcast waves, and selectively switches the received signals to provide one signal on the terminal side. Diversity television receiver amplifier for transmission via transmission line,
The television reception amplifying device demodulates reception signals amplified to a predetermined level in each of the first amplification units and the same number of first amplification units as the antennas in order to amplify signals from a plurality of antennas. A receiving unit that outputs a detection signal, a switching determination unit that sends a switching control signal to the antenna switching unit according to the signal strength of the received signal, and the received signal is switched based on the switching determination unit and output as an output signal an antenna switching unit consisting of an antenna switching means for comprises an output signal output from the antenna switching unit from the second amplification section you amplified to a predetermined level, the first amplifying unit, first First signal attenuating means for attenuating a TV signal input from the input terminal, first amplifying means for amplifying the TV signal attenuated by the first signal attenuating means, and a transmission line The first power supply superimposing means for taking in the first amplifying unit control voltage from the first output terminal and outputting the television signal amplified to the predetermined level in the first amplifying means to the first output terminal side. And a first power supply generating means for generating a first power supply voltage from the first amplifier control voltage taken in by the first power supply superimposing means, wherein the second amplifier is Second signal attenuating means for attenuating the television signal input from the two input terminals, second amplifying means for amplifying the television signal attenuated by the second signal attenuating means, and the second amplification The TV signal amplified by the means is output to the second output terminal side, and the output branching means for branching a part of the amplified TV signal, and the second supplied from the terminal side via the transmission line The power supply voltage of the second output And a second power supply superimposing means for outputting the television signal output from the output branching means to the second output terminal side, and the television signal amplified by the second amplifying means is at a predetermined level. A second automatic gain adjusting means for generating a control voltage for controlling the attenuation amount of the second signal attenuating means based on the television signal branched by the output branching means; the in response to a control voltage generated in the automatic gain control means, for generating a first amplification section control voltage variable within a range of a voltage lower than said second power supply voltage to a voltage higher than the control voltage 1 amplifying unit control voltage generating means, and the first amplifying unit control voltage generated in the first amplifying unit control voltage generating unit is output to the second input terminal side, and the second input terminal Enter from And a first amplifying unit control voltage superimposing unit for outputting the input television signal to the second signal attenuating unit, and the second amplifying unit is supplied from the terminal side via a transmission line. The first amplifying unit is generated from the first amplifying unit control voltage supplied via the transmission line via the first power generating unit. The first signal attenuating means 12 is operated by the first amplifying part control voltage generated by the first amplifying part control voltage generating means provided in the second amplifying part. Configured to be controlled.

A second aspect of the present invention, a television signal receiving amplifier according to claim 1, at least the terminal-side power generation means for generating the second power supply voltage, between the second amplifying unit with receiving an output signal from the transmission line is interposed, and a terminal-side apparatus comprising a terminal-side superimposing means for delivering a second power supply voltage via the transmission line to the second amplifying portion Configured to be

A third aspect of the present invention, a television signal receiving amplifier according to any one of claims 1 to 2, an antenna for television reception, at least the first amplifying portion and the second amplifier And a transmission line having a predetermined length interposed between the first and second sections.

According to a fourth aspect of the present invention, there is provided the television receiving amplifying device according to any one of the first to third aspects, at least between the first amplifying unit and the second amplifying unit, and The transmission line interposed between the second amplifying unit and the terminal side is configured to use a coaxial cable having an outer dimension equal to or smaller than 5 mm.

According to a fifth aspect of the present invention, in the television reception amplifying device according to any one of the first to fourth aspects, at least a television reception antenna and the first amplification unit are mounted outside the vehicle body. It was constructed so as to be built in the indicator light or advertising tower.

According to a sixth aspect of the present invention, in the television reception amplifying device according to any one of the first to fifth aspects, the antenna is constituted by a film antenna.

According to a seventh aspect of the present invention, in the television reception amplifying device according to any one of the first to sixth aspects, the television reception amplifying device is configured to receive terrestrial digital broadcasting.

According to an eighth aspect of the present invention, there is provided an amplifier for receiving a television set comprising at least an antenna for receiving a television broadcast wave and an amplifying unit for amplifying a television signal received by the antenna and transmitting the signal to a terminal side by a single transmission line. in television receiving system having a device, the television receiving amplifying device, a television receiver for amplifying apparatus according to any one of claims 1 to 7, at least, than the first amplifying unit The antenna side was configured to be installed outside the building or vehicle.

According to the first aspect of the present invention, the television signals received by the plurality of antennas 1, 1... For receiving the television broadcast waves are amplified, and the received signals are selectively switched so that one terminal is connected to the terminal side. Diversity television receiver amplifier for transmission via transmission line,
The television reception amplifying device includes the same number of first amplifying units 10, 10... As the antennas 1, 1. Of the first amplifying units 10, 10... That demodulate the reception signals amplified to a predetermined level and output detection signals, and antennas according to the signal strength of the received signals. An antenna switching section 9 comprising a switching determination means 45 for sending a switching control signal to the switching means 46, the antenna switching means 46 for switching the received signal based on the switching determination means 45 and outputting it as an output signal; a second amplification section 20 that amplifying the output signal output from the switching means 9 to a predetermined level, made, the first amplifying unit 10 attenuates the television signal input from the first input terminal In1 First to let The signal attenuating means 12, the first amplifying means 13 for amplifying the television signal attenuated by the first signal attenuating means 12, and the first amplifying unit control voltage supplied via the transmission line 2 A first power supply superimposing means 15 for taking in the first output terminal Out1 and outputting the television signal amplified to a predetermined level by the first amplifying means 13 to the first output terminal Out1 side, A first power generation unit 16 for generating a first power supply voltage from the first amplification unit control voltage taken in by the power supply superimposing unit 15, and the second amplification unit 20 has a second input. Second signal attenuating means 22 for attenuating the television signal input from the terminal In2, second amplifying means 23 for amplifying the television signal attenuated by the second signal attenuating means 22, and the second amplification The television signal amplified in the stage 23 is output to the second output terminal Out2 side, and an output branching unit 24 for branching a part of the amplified television signal is supplied from the terminal side via the transmission line 4. A second power supply superimposing means 25 for taking in the second power supply voltage to be output from the second output terminal Out2 and outputting the television signal output from the output branching means 24 to the second output terminal Out2 side. The amount of attenuation of the second signal attenuating means 22 is controlled based on the television signal branched by the output branching means 24 so that the television signal amplified by the second amplifying means 23 has a predetermined level. a second automatic gain control unit 27 for generating a control voltage for, corresponding to a control voltage generated in the automatic gain control unit 27 of the second, before a voltage higher than the control voltage The first amplifying unit control voltage generating unit 28 that generates a first amplifying unit control voltage that is variable within a voltage range lower than the second power supply voltage, and the first amplifying unit control voltage generating unit 28 generates the first amplifying unit control voltage. The first amplifying unit control voltage thus outputted is outputted to the second input terminal side In2, and the television signal inputted from the second input terminal In2 is outputted to the second signal attenuating means 22. Amplifying unit control voltage superimposing means 21, wherein the second amplifying unit 20 is configured to operate with a second power supply voltage supplied from the terminal side via the transmission line 4. The amplifying unit 10 is operated by a first power supply voltage generated via the first power supply generating unit 16 from a first amplifying unit control voltage supplied via the transmission lines 3 and 2, and The first signal attenuation means 12 is the front Since it is configured to be controlled by the first amplifying unit control voltage generated in the first amplifying unit control voltage generating means 28 provided in the second amplifying unit 20, the strongest radio wave is always received. Thus, it is possible to provide a TV reception amplifying apparatus with an automatic gain adjustment circuit having a wide dynamic range that can switch the reception output of the antenna and can perform stable reception.

According to the second aspect of the invention, a television signal receiving amplifier according to claim 1, at least, a terminal-side power generation means 31 for generating the second power supply voltage, the second amplifying section 20 And a terminal-side superimposing means 32 for receiving an output signal from the transmission line 4 interposed between the first amplifier 20 and the second amplifying unit 20 for transmitting a second power supply voltage via the transmission line 4. a terminal-side apparatus 30 comprising, since it is configured in so that comprises a,
For example, it is possible to provide a television reception amplifying device with an automatic gain adjustment circuit suitable for a system that supplies power from a terminal-side device, such as a television receiver or a terrestrial digital broadcast reception tuner that receives terrestrial digital broadcasts.

According to a third aspect of the present invention, the television reception amplification device according to any one of the first to second aspects , the television reception antenna 1, at least the first amplification unit 10 and the second amplification unit. Since the transmission line 3 having a predetermined length interposed between the amplifying unit 20 and the amplifying unit 20 is provided in advance,
Thus, it is possible to provide a television receiving amplifying device with a simple wiring automatic gain adjustment function.

According to a fourth aspect of the present invention, in the television receiver amplifying device according to any one of the first to third aspects, at least the first amplifying unit 10 and the second amplifying unit 20 And the transmission lines 3 and 4 interposed between the second amplifying unit 20 and the terminal side are configured to use a coaxial cable having an outer dimension equal to or smaller than 5 mm.
For example, it is possible to provide an amplifying apparatus for TV joint reception with an automatic gain adjustment circuit that can be easily pulled into a building such as a building or a condominium or a taxi or a bus.

According to a fifth aspect of the present invention, in the television reception amplifying device according to any one of the first to fourth aspects, at least the television reception antenna 1 and the first amplification unit 10 are connected to a vehicle body. Since it is configured to be built in an externally installed indicator light or advertising tower,
In taxis and buses, it is possible to install a TV joint reception amplifying device with an automatic gain adjustment circuit that can stably receive TV broadcasts without significantly changing the appearance.

According to the invention of claim 6 , in the television receiver amplifying device according to any one of claims 1 to 5 , the antenna 1 is constituted by a film antenna.
This makes it possible to provide an amplifying apparatus for TV reception with an automatic gain adjustment circuit that can be manufactured at low cost and is easy to install.

According to a seventh aspect of the present invention, in the television reception amplifying device according to any one of the first to sixth aspects, the television reception amplifying device is configured to receive terrestrial digital broadcasting. ,
It is possible to provide an amplifying apparatus for receiving television with an automatic gain adjustment circuit that does not deteriorate in C / N even in an area where the reception level is weak and can stably receive in an area where the reception level is strong.
In addition, in the current situation where simultaneous broadcasting of analog terrestrial broadcasting and digital terrestrial broadcasting is being performed, even if reception is optimal, for example, terrestrial television broadcasting is completely digitized and only terrestrial digital broadcasting is achieved. and a to come, or multichannel is made increasingly channel of the UHF band, by or is energizing of, even when the input level to the amplifier is increased, without particular the switching operation, the optimal Therefore, a gain adjustment apparatus for television reception having a wide dynamic range, which is said to be capable of stable reception by automatically adjusting the gain so as to obtain a stable output level, can be provided.

According to the invention of claim 8 , a television receiver comprising at least an antenna for receiving a television broadcast wave and an amplifying unit for amplifying a television signal received by the antenna and transmitting it to the terminal side by a single transmission line. in television receiving system having a use amplifier, the television receiving amplifying device, a television receiver for amplifying apparatus according to any one of claims 1 to 7, at least, the first amplification Because the antenna side is installed outside the building or vehicle from the unit, for example, a building for a building or a condominium, or a TV joint reception amplifying device that can be easily pulled into a car such as a taxi or a bus. A television receiving system can be provided.

Hereinafter, an example of an embodiment embodying the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic block diagram showing a first embodiment of a television receiving amplifier according to the present application, and FIG. 2 shows a different embodiment. FIG. 3 shows an example in which a plurality of antennas are provided. FIG. 4 is a schematic block diagram showing a second embodiment of the present application. FIG. 5 is a schematic view when the television receiving amplification device of the present application is attached to the vehicle body. The embodiment shown in FIGS. 1 to 3 is a reference example including the content (a part of the configuration of the invention) which is the basis of the present invention, and the embodiment shown in FIG. 4 is applied with the present invention. It is an example.

A first embodiment of the present application will be described with reference to FIG. In this figure, reference numeral 1 denotes an antenna for receiving a television broadcast, and according to an embodiment of the present application, an embodiment is shown which is a terrestrial digital UHF antenna.
Reference numeral 10 denotes a first amplifying unit which is built in the power feeding unit of the antenna or is connected to the antenna via a coaxial cable in the vicinity of the power feeding unit. The first amplifying unit 10 is a preamplifier composed of a low-noise transistor, IC, or the like, for example, a printed wiring comprising a high-frequency circuit in a case formed of a synthetic resin or a metal material not shown. It is comprised so that a board may be accommodated.
A reception signal received by the antenna 1 is input to the printed wiring board housed inside the amplifying unit via an input terminal In1 attached so as to protrude from the case. An input received signal is generally composed of a capacitor and a coil not shown in the figure, and a band pass filter, a high pass filter, etc. configured to pass a UHF band signal with a VHF band signal as a stop band. Then, the signal is input to the first amplifying means 13-1.

The first amplifying means 13-1 is a high frequency amplifier circuit composed of, for example, a transistor or an IC as an amplifying element, and the amplifying element is selected and a bias design is made so as to reduce noise. After being amplified to a predetermined level by the amplifying unit 13-1, the output signal from the amplifying unit 13-1 is input to the first signal attenuating unit 12 that attenuates the signal within a predetermined range.
The first signal attenuating means 12 is a so-called π-type attenuator composed of a PIN diode, and obtains an amount of attenuation corresponding to a first amplifying unit control voltage supplied via a transmission line described in detail later. It is configured.

Next, the signal passing through the first signal attenuating means 12 is further amplified to a predetermined level by the first amplifying means 13-2. This amplifying means is also a high-frequency amplifying circuit composed of, for example, a transistor or an IC as an amplifying element.
Further, the amplifying unit 13-2 outputs the high frequency signal to the output terminal Out1 through a capacitor connected to the amplifying unit 13-2 and passing the high frequency signal amplified to a predetermined level. A first power supply superimposing means 15 for connecting the first amplifying unit control voltage from the output terminal Out1 into the first amplifying unit 10 is connected via a choke coil that passes the power supply voltage and cuts off the high frequency signal. ing.

16 generates a DC constant voltage for operating at least the amplifying units 13-1 and 13-2 from the first amplifying unit control voltage taken in via the first power supply superimposing unit 15 from the output terminal Out1. For example, a first power source generating means composed of, for example, a series regulator, a three-terminal regulator, etc., and the DC constant voltage generated in the first power source generating means 16 is the first power source described in the claim hole. Voltage.

Reference numeral 20 denotes a second amplifying unit, which is formed on a printed wiring board by a high-frequency amplifying circuit made up of a transistor, IC, etc. as an amplifying element that is provided on the terminal side via a coaxial cable having a predetermined length. The amplifying unit is housed in a case made of, for example, a synthetic resin material or a metal material not shown in the drawing.
The output signal transmitted from the first amplifying unit 10 via the coaxial cable 3 is input to the amplifying unit 20 from the input terminal In2. The input output signal is composed of capacitors, coils, etc. formed on a printed wiring board not shown in the figure, for example, through a filter means of a high-pass filter having a VHF band as a stop band and a UHF band as a pass band. To the second signal attenuation means 22 for attenuating the output signal within a predetermined range.

The second signal attenuating means 22 is a so-called π-type attenuator composed of, for example, a PIN diode, and is configured to obtain an attenuation amount corresponding to the control voltage.
Next, the signal that has passed through the second signal attenuating means 22 is amplified to a predetermined level by the second amplifying means 23. The second amplifying means 23 is a high-frequency amplifier circuit composed of, for example, a transistor or an IC as an amplifying element. In particular, the selection and bias design of the high-frequency element is performed so as to be a high output type having a margin in output level. The signal is amplified to a predetermined level by the amplifying means 23 and then input to the branch output means 24.

In the embodiment of the present application, the output branching means 24 is a branch circuit comprising a branch coil formed by winding a polyurethane wire around a ferrite core, for example, and outputs the output signal of the second amplifying means 23 to the second output terminal Out2 side. In addition, a part of the amplified television signal is output to the branch terminal 24a.
Further, the output of the output branching means 24 is a TV signal output from the output branching means 24 to the second output terminal Out2 via a capacitor and supplied from the terminal side via the transmission line 4. A second power superimposing means 25 is connected to allow the second power supply voltage to pass through and to be taken into the second amplifying unit 20 via a choke coil that blocks the television signal.

Further, the branching terminal 24a of the output branching means 24 is connected to the branching terminal 24a through a filter means 29 (for example, a bandpass filter) which is not shown in the drawing and which passes a signal of a predetermined band, for example, comprising a capacitor and a coil. The television signal output from the branch terminal 24a of the output branch means 24 through the filter means 29 is detected so that the television signal amplified by the second amplification means 23 has a predetermined level, and this detection voltage is detected. Is connected to a second automatic gain adjusting means 27 for generating a control voltage for controlling the amount of attenuation of the second signal attenuating means 22, and the second signal attenuating means 22 is connected to the second signal attenuating means 22. The second amplifying unit 20 operates as an amplifier with automatic gain adjustment, and is controlled by the control voltage generated by the automatic gain adjusting means 27. .

The second automatic gain adjusting means of the present application takes in a television signal from the branch terminal 29a via the filter means 29 having a predetermined pass band and detects the intensity of the output level in the second amplifying unit 20. For example, a detection unit composed of a detection circuit using a diode for signal detection and a smoothing circuit composed of a capacitor, a resistor, and the like, and a detection voltage output from the detection unit according to the intensity of the output level are taken in, and a reference value It is made up of an arithmetic unit having an arithmetic circuit composed of, for example, an operational amplifier and a resistor, for determining whether or not the output level exceeds the reference value.
In other words, the intensity of the output level in the second amplifying unit is detected by the detecting unit, and the operation unit determines whether the detected voltage exceeds the reference voltage. If the detected voltage is higher than the reference voltage, A signal corresponding to the detected voltage is output as a control signal from the arithmetic unit, and the second amplifying unit 22 performs automatic gain adjustment by controlling the second signal attenuating means 22 by this control signal. It amplifies.
When the detection voltage is lower than the reference voltage, the signal output from the calculation unit is almost zero, the control voltage is not applied to the second signal attenuation means 22, and the second signal attenuation means 22 Therefore, the automatic gain adjustment circuit operates as a normal amplifying unit 20 that does not operate.

Furthermore wherein the second automatic gain control unit 27, corresponding to a control voltage generated in the automatic gain control unit 27 of the second, lower voltage than the second power supply voltage to a voltage higher than the control voltage The first amplifying unit control voltage generating means 28 is connected to generate a first amplifying unit control voltage that varies within the range of, for example, an arithmetic circuit composed of an operational amplifier and a resistor.
Further, between the input terminal In2 and the second signal attenuating means 22, the first amplifying part control voltage generated in the first amplifying part control voltage generating means 28 is passed and the high frequency signal is cut off. The first amplifying unit control voltage is output to the second input terminal In2 via the choke coil, and the television signal input from the second input terminal In2 is passed through the first amplification unit. First amplifying unit control voltage superimposing means 21 for outputting a high frequency signal to the second signal attenuating means 22 through a capacitor for blocking the unit control voltage is provided.
According to the embodiment of the present application, the second amplifying means 23 constituting the second amplifying unit 20 is not limited to the example shown in the embodiment of the present application, but like the first amplifying unit 10. However, the present invention is not limited to the embodiment.

Further, in the embodiment of the present application, the first amplifying unit 10 drives the first amplifying unit 13 and controls the first signal attenuating unit 12 by the first amplifying unit control voltage from the second amplifying unit 20. For example, as shown in FIG. 2, the second amplifying unit 20 is provided with a current passing circuit that passes the second power supply voltage from the output terminal Out2 to the input terminal In2. The second amplifying unit 20 operates with the second power supply voltage and supplies the second power supply voltage to the first amplifying unit 10 via the transmission line 3 to drive the first amplifying unit 10. . Furthermore, the first amplification unit control voltage output from the automatic gain adjustment means 27 provided in the second amplification unit 20 is separated from the first amplification unit by a control line provided separately from the transmission line 3. The first signal attenuating means 12 provided in the first amplifying unit 10 may be connected to be controlled. In this case, the first amplifier control voltage generating means 28 is not necessary.
Needless to say, this embodiment can be applied to the following embodiments.

Reference numeral 30 denotes a terminal-side device, and at least high-frequency from the transmission line 4 interposed between the terminal-side power generation means 31 that generates the second power supply voltage and the second amplifying unit 20. The television signal from the amplifying unit is received through a capacitor that passes the signal and blocks the second power supply voltage, and passes through the choke coil that passes the second power supply voltage and blocks the high-frequency signal. Terminal side superimposing means 32 for sending the first amplifier control voltage toward the second amplifier 20 is provided.
Generally, the terminal device 30 may be a digital home appliance such as a television receiver or an HDD recorder, or a tuner for terrestrial digital broadcasting. Further, the amplifier unit 20 is configured to be inserted into a coaxial cable interposed between the terminal-side device 30 and the amplifier unit 20 and to take power from, for example, a socket of a car cigarette lighter. The configuration is not particularly limited, such as a power supply inserter for supply.

FIG. 3 shows a different example of the first embodiment of the present application. In addition, what shows the same structure as the said Example attaches | subjects the same code | symbol, and abbreviate | omits detailed description. In this embodiment, a plurality of antennas 1 for receiving television are provided, and the same number of first amplifying units 10, 10... Are provided for the antennas 1, 1,. , 10... Are mixed in the mixer 8 and sent to the second amplifying unit using a single coaxial transmission line 3, and the mixer 8 has an output terminal. Thus, the automatic gain adjustment circuits of the first amplification unit and the second amplification unit operate on the signal from the antenna having the largest received signal.

Next, a second embodiment of the present invention will be described with reference to FIG. In the following description, the same components as those of the television joint reception amplifying device of the first embodiment are given the same reference numerals, and detailed description thereof is omitted.

In this embodiment, a plurality of antennas 1 are provided, and the reception signals of the respective antennas are input to the antenna switching unit 9 via the first amplifying units 10 prepared in the same number as the antennas.
The antenna switching unit 9 includes a receiving unit 41, 41... That detects a part of the reception signal output from each of the first amplification units 10, 10,. A switching determination means 45 for sending a switching control signal to the antenna switching means 46 according to the signal strength of the signal, and an antenna switching means 46 for switching the received signal based on the switching determination means 45 and outputting it as an output signal. In the switching determination means 45, a comparison is made with a threshold value with respect to the signal strength of the received signal, which is a criterion for switching the antenna switching means 46, and the antenna switching means 46 is switched based on this comparison. Has been. As a result, not only the reception signal from the optimum receiving antenna can be obtained, but also the first amplifying unit connected to the non-receiving antenna can be separated from the receiving system, and this amplifying unit is prevented from becoming a noise source. It can be done.
In the embodiment of the present application, an example was shown in which a high-frequency switch composed of, for example, a relay was used as the antenna switching means. However, instead of this relay, an attenuator was provided on the signal line from the antenna and selected. The switching determination means 45 sets the attenuation amount of the attenuator so that the attenuation amount of the attenuator interposed in the signal line of the receiving antenna becomes zero and the attenuation amount interposed in the signal line of the unselected receiving antenna becomes maximum. If it is configured to be switchable, the same effect as the high-frequency switch can be obtained.
The antenna switching unit 9 is provided with a current passing circuit so that the first amplifying unit control voltage supplied from the second amplifying unit 20 passes from the output terminal side to the input terminal side.

Next, a specific wiring system example using the television receiving amplifier of the present application will be described with reference to FIG. In this embodiment, a configuration example is shown in which at least the antenna 1 and the first amplifying unit 10 are arranged inside an indicator lamp 101 installed on the roof of a car 100 such as a taxi.
In this figure, an antenna 1 is an omnidirectional UHF digital broadcast antenna. The antenna shown in the embodiment is written to indicate the state of installation, and is not particularly limited to this shape. For example, a conductive material is used on the surface of a thin transparent insulator. An antenna element may be formed.
The first amplifying unit 10 in the embodiment of the present application is composed of a low noise amplifying circuit having a noise figure of 2.5 dB and a gain of 20 dB composed of a transistor, an IC or the like as an amplifying element. The first amplifying unit 10 is connected to the output of the antenna, for example, by a coaxial cable in the indicator lamp 101 and in the vicinity of the antenna. The first amplifying unit 10 is connected to the antenna. 1 may be built in a power feeding unit, or the terminal structure may be configured as a male (male) or a female (female) so that the output terminal of the antenna 1 and the input terminal of the first amplifying unit 10 can be directly connected. In addition, it is preferable that the connection is made as short as possible to reduce the C / N degradation of the received signal.
In this embodiment, since the antenna 1 and the first amplifying unit 10 are built in the indicator lamp, the antenna 1 and the first amplifying unit 10 are housed in a case of a complicated structure having a waterproof structure. There is no need to do this, and it can be configured at low cost.

The received signal amplified to a predetermined level in the first amplifying unit 10 is connected to the second amplifying unit 20 via the coaxial cable 3. The coaxial cable 3 is preferably a coaxial cable having a bendability of 2C or smaller diameter, for example, which facilitates installation according to the line of the vehicle body and facilitates drawing into the vehicle body. . Note that the coaxial cable interposed between the first amplifying unit 10 and the second amplifying unit may have a predetermined length and may be connected in advance or prepared separately. It may be configured to be connected with a connector.

Next, the second amplifying unit 20 will be described. The second amplifying unit is installed in the trunk space of the car, the gap under the seat, or the like via the coaxial cable 3.
The second amplifying unit 20 is a high-output type high-frequency circuit having an amplification degree of about 30 dB and composed of a transistor, an IC, or the like as an amplifying element. It is connected to the terminal side device of the tuner.

As described above, the television reception amplifying apparatus of the present application is built in the power feeding section of the antenna, or is installed in the vicinity of the antenna, and includes a first signal attenuating means 12 and a first amplifying means 13. And a second amplifying unit 20 comprising at least a second signal attenuating means 22 and a second amplifying means 23 installed in the vicinity of the terminal-side device 30 which is a tuner for receiving digital terrestrial broadcasting. Consist
The second amplifying unit 20 is configured to operate with a second power supply voltage supplied from the terminal side via the transmission line 4;
The first amplifying unit 10 operates from the second power supply voltage supplied via the transmission line 8 by the first power supply voltage generated via the first power supply generation means 16, and Since the first signal attenuating means 12 is configured to be controlled by the second power supply voltage generated in the second power supply generating means 28 provided in the second amplifying unit 20,
The dynamic range with respect to changes in input level is wide, and even if the received signal is small, it can be received without C / N degradation. Also, it is optimal for use in areas where the transmission power of terrestrial digital broadcast waves is not at full power at present, or where it is not stably output, such as an amplifier for receiving terrestrial digital broadcasts. The TV broadcast is completely digitized after 2011 in a state of being installed so as to be in a reception state, and multi-channel radio waves are input or transmission power is increased from the current reception state. Even if a signal with a higher level is input to the amplifying device, the optimum output level is automatically obtained.
In addition, when considering use in a moving body such as a car, the electric field strength may change greatly during a short period of movement as well as the fluctuation in the reception level as described above. Compared with an amplifying device that switches the setting of the attenuator by operating the switch during movement (ie during operation), the switch is not operated to improve the safety. It is.
In addition, since no switch operation is performed, the installation location of the second amplifying unit is not limited, and an extremely convenient television receiving amplifying device can be provided.

The present invention is not limited to the above-described embodiment, and can be implemented by appropriately changing the configuration of each part without departing from the spirit of the present invention, as exemplified below.

1 is a schematic block diagram illustrating a first embodiment of a television reception amplification device according to the present invention. It is a schematic block diagram which shows the Example from which 1st Embodiment differs. It is a schematic block diagram which shows the Example provided with two or more antennas. It is a schematic block diagram which shows 2nd Embodiment which concerns on this application. It is the schematic when the amplification apparatus for television reception of this application is built in the indicator lamp attached to the vehicle body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 * 3 * 4 Transmission line, 8 ... Mixer, 9 ... Antenna switching part, 10 ... 1st amplification part, 12 ... 1st signal attenuation means, 13 ... 1st amplification means, 15 ... 1st power supply superimposing means, 16 ... 1st power supply generation means, 20 ... 2nd amplification part, 21 ... 1st amplification part control voltage superimposition means, 22 ... 2nd signal attenuation means, 23 ... 2nd Amplifying means, 24 ... output branching means, 24a ... branch terminal, 25 ... second power supply superimposing means, 27 ... second automatic gain adjusting means, 28 ... first amplifier control voltage generating means, 29 ... filter means , 30... Terminal side device, 31... Second power generation means, 32... Second power superimposing means, 41... Receiving unit, 45.

Claims (8)

The television signals received by a plurality of TV antenna for receiving broadcast waves and respectively amplified, the television receiving amplifier of diversity system for transmitting selectively switched to the terminal side by a single transmission line the received signal ,
The television reception amplifying device demodulates reception signals amplified to a predetermined level in each of the first amplification units and the same number of first amplification units as the antennas in order to amplify signals from a plurality of antennas. A receiving unit that outputs a detection signal, a switching determination unit that sends a switching control signal to the antenna switching unit according to the signal strength of the received signal, and the received signal is switched based on the switching determination unit and output as an output signal the antenna switching means consisting of an antenna switching unit comprises an output signal output from the antenna switching unit from the second amplification section you amplified to a predetermined level,
The first amplifying unit amplifies the television signal attenuated by the first signal attenuating means and the first signal attenuating means for attenuating the television signal input from the first input terminal. Amplifying means and a first amplifying unit control voltage supplied via a transmission line are taken in from the first output terminal, and a television signal amplified to a predetermined level by the first amplifying means is connected to the first output terminal side. First power superimposing means for outputting to the first power supply generating means for generating a first power supply voltage from the first amplifier control voltage taken in by the first power superimposing means. Consist
The second amplifying unit includes a second signal attenuating unit for attenuating the television signal input from the second input terminal, and a second signal amplifying the television signal attenuated by the second signal attenuating unit. Amplifying means, output branch means for outputting the television signal amplified by the second amplifying means to the second output terminal side, and branching a part of the amplified television signal, and transmission from the terminal side Second power superimposing means for taking in the second power supply voltage supplied via the line from the second output terminal and outputting the television signal output from the output branching means to the second output terminal side And the amount of attenuation of the second signal attenuating means based on the television signal branched by the output branching means so that the television signal amplified by the second amplifying means becomes a predetermined level. Generate control voltage A second automatic gain control means, corresponding to a control voltage generated in the automatic gain control means of the second, in the range of lower voltage than the second power supply voltage to a voltage higher than the control voltage signal A first amplifying unit control voltage generating unit configured to generate a variable first amplifying unit control voltage; and a first amplifying unit control voltage generated in the first amplifying unit control voltage generating unit as the second input. A first amplifying unit control voltage superimposing means for outputting to the second signal attenuating means and outputting the television signal inputted from the second input terminal to the terminal side,
The second amplification unit is configured to operate with a second power supply voltage supplied from the terminal side via a transmission line,
The first amplifying unit is operated by a first power supply voltage generated via the first power supply generating means from a first amplifying unit control voltage supplied via a transmission line, and the first amplifying unit operates. diver signal attenuation means is characterized by being configured to be controlled by the first amplification section control voltage generated in the first amplification section control voltage generating means provided in said second amplifying section A city-type television receiver amplifier. The television receiving amplifying device according to claim 1,
At least an output signal from a transmission line interposed between the terminal-side power generation means for generating the second power supply voltage and the second amplification unit is received and transmitted to the second amplification unit A terminal-side device comprising terminal-side superimposing means for sending a second power supply voltage via a line;
A television receiver amplifying device characterized by comprising: A television receiving amplifying device according to any one of claims 1 to 2,
A television reception amplifying apparatus, comprising: a television reception antenna; and a transmission line having a predetermined length interposed between at least the first amplification unit and the second amplification unit. At least the transmission line interposed between the first amplifying unit and the second amplifying unit and between the second amplifying unit and the terminal side has an outer dimension equal to or smaller than 5 mm. 4. The television receiving amplifying device according to claim 1, wherein a coaxial cable having a diameter is used . 5. The apparatus according to claim 1, wherein at least a television receiving antenna and the first amplifying unit are built in an indicator lamp or an advertising tower mounted outside a vehicle body. An amplifying apparatus for television reception as described in the paragraph . The antenna television receiving amplifying device according to any one of claims 1 to 5 characterized by comprising a film antenna. The television receiving amplifying device according to any one of claims 1 to 6 characterized in that the receiving amplifier is for terrestrial digital broadcasting receiver. Television receiving system comprising a television receiving amplifying device comprising at least an antenna for receiving a television broadcast wave and an amplifying unit for amplifying a television signal received by the antenna and transmitting it to a terminal side by a single transmission line In
  The television receiving amplifying device according to any one of claims 1 to 7, wherein the television receiving amplifying device is
  A television receiving system, wherein at least the antenna side of the first amplifying unit is installed outside a building or a vehicle.

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