JP2664299B2 - TV door phone equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television door phone used in an apartment house or the like.

[0002]

2. Description of the Related Art Hitherto, a TV door phone device capable of monitoring a video and communicating with a collective terminal with a TV camera has been used in an apartment house or the like. FIG.
FIG. 1 is a block diagram of a conventional TV door phone device. 6, a television camera, a video signal output unit of the set entrance door station 101 disposed in the set entrance near is connected to an input of video signal processor 102 via the coaxial cable 607 _1. Audio signal output portion of the aggregate entrance door station 101, parallel cables 609 _1, the audio signal processor 103
And via a parallel cable 609 ₂ are connected to the adapter 604 _1. The output of video signal processor 102 is connected to the adapter 604 ₁ via the coaxial cable 607 _2. Adapter 604 ₁ is connected to the room 608 ₁ disposed in the room through the coaxial cable 607 _3. The living room unit 608 ₁ includes a monitor TV 104 ₁ and an intercom 105 ₁ . The video signal output portion of the adapter 604 ₁ with is connected to the adapter 604 ₂ via the coaxial cable 607 _4, the audio signal output section of the adapter 604 ₁ via a parallel cable 609 ₄ Adapter 6
04 ₂ is connected. Adapter 604 ₂ of the video signal output section with through the coaxial cable 607 ₅ are connected to the room 608 ₂ disposed in another room, the room unit is the audio signal output section via the parallel cable 609 ₅ 608 ₂
It is connected to the. Similarly, the adapter 604 _n is connected to the living room 608 _n via a coaxial cable 607 _k and a parallel cable 609 _k .

The adapters 604 _{1 to} 604 _n have the same configuration, and differ in that their own station numbers are different. In addition, all of the room units 608 _{1 to} 608 _n have the same configuration. Figure 7 is a detailed circuit diagram of the adapter 604 ₁ are denoted by the same reference numerals as in FIG. 6.

In FIG. 7, a video signal from a video signal processor 102 is transmitted to a living room unit 6 via a changeover switch 701.
To 08 ₁ or adapter 604 ₂ are selectively connected. Monitor power signal from the audio signal processor 103 is selectively connected to the room 608 ₁ or adapter 604 ₂ via the changeover switch 702. Audio signal from the audio signal processor 103 is selectively connected via the switch 703 to the room 608 ₁ or adapter 604 _2. Data signal representing the room unit number corresponding to the own number of the adapter from the audio signal processor 103 is connected to the adapter 604 ₂ via a data identification circuit 704.

[0005] The operation of the conventional TV intercom apparatus configured as described above will be described with reference to Figs.
The video signal output is captured by a set entrance door station 101 includes a video signal processor 1 via the coaxial cable 607 ₁
02 is output. Wherein after the image signal which amplification processing or the like is performed by the video processor 102, room unit via the coaxial cable 607 _2, the adapter 604 ₁ and the coaxial cable 607 ₃ 6
08 ₁ is output. Thereby, the monitor TV 104 ₁
Then, a video display corresponding to the video signal from the collective entrance slave unit 101 is performed.

On the other hand, (in this case, a signal representing the room 608 ₁₎ data signals from the set entrance door station 101 and the audio signal is output to the audio signal processor 103 via a parallel cable 609 _1. The audio signal after processing such as amplification is performed by the audio signal processor 103, is output to the adapter 604 ₁ via a parallel cable 609 _2. In the adapter 604 _1, memory device compared by comparing the stored (not shown) and own number the data signal circuit (not shown), if they match, the local station side changeover switch 701 to 703 That is, it is controlled to connect to the room unit 608 _1, and if they do not match, the adapter 604 ₂
Control to connect to the side. Thereafter, the adapter 60
.. Perform the same operation as that of 8 ₂ ,..., And the room units 608 ₁ , 608 ₂ ,. .

As described above, the living room unit 608 in each living room is provided.
_1, 608 _2, by ..., together with the video can be monitored set entrance door station 101, set the entrance door station 101 and the room 608 _1, 608 _2, a call between the ... performed.

[0008]

In the above-mentioned television intercom apparatus, since the coaxial cable is used to prevent the deterioration of the video signal, there is a problem that the cost becomes extremely high and the wiring process becomes extremely complicated. Was. In addition, since the baseband signal of the NTSC signal is used as the video signal, there is a problem that when the transmission distance is increased, the image quality is deteriorated such as the image contrast is reduced.

Further, since the specific bandwidth is wide (several tens of Hz to 4 MHz) and the attenuation characteristic is f ^-1 characteristic in a low frequency range, the f ^-1/2 characteristic is obtained as the frequency is increased. There is a problem that it is difficult to correct. In addition, since the coaxial cable is an unbalanced line,
There is a problem that it is weak to radio wave interference below MHz.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a television intercom apparatus capable of preventing deterioration in image quality and facilitating wiring processing.

[0011]

In order to achieve this object, a television intercom apparatus according to the present invention comprises a collective entrance unit having a television camera and a plurality of living rooms connected to the collective entrance unit via respective adapters. A video doorphone device for performing a call between the collective entrance unit and the selected living room unit and monitoring on a monitor television of the indoor unit based on a video signal transmitted from the collective entrance unit, Modulating means for modulating the video signal from the device and outputting to the adapter via the parallel cable, demodulating means for demodulating the modulated video signal received from the adapter via the parallel cable and outputting to the living room unit, A distributor for distributing the modulated video signal to the next-stage adapter, and high-frequency compensation means for compensating for the high frequency range of the modulated video signal and outputting to the next-stage adapter. The distributor is distributed to the next-stage adapter via a balanced input section to which the video signal is input, a first balanced output section for distributing the video signal input to the balanced input section to the demodulation means, and the high-frequency compensation means. And a second balanced output section.

[0012]

In this television intercom apparatus, the video signal from the main entrance unit is modulated by the modulation means, transmitted through a parallel cable, demodulated by the demodulation means from the adapter, and displayed on the living room. . on the other hand,
The video signal is distributed by the distributor of the adapter and sent to the next-stage adapter via the high-frequency compensation means, and the video signal is subjected to high-frequency compensation, thereby preventing deterioration in image quality.

[0013]

FIG. 1 is a block diagram showing an embodiment of the present invention, and the same parts as those in FIG. 6 are denoted by the same reference numerals. In Figure 1, a video signal output unit of the set entrance door station 101 disposed in the set entrance near a television camera, a parallel cable 109 _1, which is a kind of FM modulation circuit 110 and the telephone communication line as a modulation means The input is connected to an input section of a video signal processor 102 that performs amplification processing of a video signal and the like. Voice input and output portion of the aggregate entrance door station 101, via a parallel cable 108 _1, is connected to the audio signal processor 107 for performing amplification processing and the like of the audio signal. Output unit of the output unit and the audio signal processor 107 of the video signal processor 102, respectively, are connected to the adapter 103 ₁ via a parallel cable 109 _2, 108 _2. Adapter 103 ₁
It is connected to the room 106 ₁ disposed in the room via a parallel cable 109 _3, 108 _3. Room device 106
₁ comprises an FM demodulation circuit 111 _1, TV monitor 104 ₁ and interphone 105 ₁ as demodulation means. Further, the video signal output of the adapter 103 ₁ is connected to the adapter 103 ₂ via a parallel cable 109 _4,
Audio signal output section is connected to the adapter 103 ₂ via a parallel cable 108 _4. Adapter 103 ₂ has the same structure as the adapter 103 _1, only own number stored in the channel selection number storage device (not shown) inside is different.
Adapter 103 ₂ of the video signal output section parallel cable 10
9 ₅ and the FM demodulation circuit 111 ₂ are connected to the room unit 106 ₂ arranged in another room, and the audio signal output unit is connected to the room unit 106 ₂ via the parallel cable 108 _5. I have. The room unit 106 ₂ is configured the same as the room unit 106 ₁ .

Hereinafter, similarly, the adapter 103 _n , the parallel cables 108 _n and 109 _n , the FM demodulation circuit 111 _n and the living room 106 _n are connected. The adapter 103 _n has a configuration similar to that of the adapter 103 _1, and differs only in the own station number stored in a channel selection number storage device (not shown). The living room unit 106 _n is configured the same as the living room unit 106 ₁ .

[0015] Figure 2 is a detailed circuit diagram of the adapter 103 ₁ are denoted by the same reference numerals as in FIG. 1. FIG.
, The video signal from the video signal processor 102 is output to the distribution circuit 201. One output of the distribution circuit 201 is connected to the monitor TV 10 via the FM demodulation circuit 111 _1.
4 is connected to _one addition, distribution circuit other output portion compensation circuit 202 as there high frequency compensating means in the amplifier circuit to compensate for the high frequency response of 201, a limiter amplifier for equalizing the signal level at a constant value 203 It is connected to the adapter 103 ₂ via the.

[0016] On the other hand, the data signal which is the output signal of the audio signal processor 107 is output to the data decision circuit 204 is outputted to the adapter 103 _2. The data identification circuit 204 compares the own station number set in a channel selection number storage device (not shown) provided therein with the room number, and switches according to whether or not the comparison result matches. Switches 205 and 206 are switched. One output terminal of the switch 205 is connected to a monitor television 104 _1, the other output terminal is connected to the adapter 103 _2. Monitor power signal as a power source is switched connected to a monitor television 104 ₁ or adapter 103 ₂ via the changeover switch 205.

The audio signal is supplied to a changeover switch 206.
Via the interphone 105 ₁ or the adapter 103 ₂
It is connected to the. The operation of the TV intercom apparatus configured as described above will be described below. In FIG. 1 and FIG. 2, first, a room number is set in a key matrix (not shown) of the collective entrance unit 101. , The specific room units 106 _{1 to} 106 _n are called. A data signal, a sound signal, a monitor power supply signal, and a video signal representing the room number of the room unit to be the communication partner are output from the collective entrance terminal 101.

The video signal from the collective entrance terminal 101 is F
After being FM modulated by M modulation circuit 110, is output to the video signal processor 102 via a parallel cable 109 _1. The FM-modulated video signal is supplied to a video signal processor 1
02 is subjected to processing such as amplification by the adapter 10
3 is output to _1. The audio signal, the data signal, and the monitor power signal from the collective entrance terminal 101 are output to the audio signal processor 107 via the parallel cable 108 ₁ in parallel. The audio signal processor 107 subjects the audio signal to amplification processing and the like, and the data signal and the monitor power supply signal are subjected to the parallel cable 108 ₂ without any processing.
Through, it is outputted to the adapter 103 ₁ in parallel.

The data identification circuit 20 in the adapter 103 ₁
4 compares the living room unit number represented by the data signal with the own station number, and when they match, the changeover switches 205 and 20
6 is connected to the state shown in FIG. Thus, the audio signal of the audio signal processor 107 is connected to the intercom 105 ₁ through the changeover switch 206, a set entrance door station 1
01 and the intercom 105 ₁ can communicate with each other. Further, since the monitor power signal is supplied to the monitor television 104 ₁ through the changeover switch 205, a monitor TV 1
04 ₁ will be capable of displaying active state. Thus, after demodulating a video signal supplied through the distribution circuit 201 by the FM demodulation circuit 111 _1, the image display on the monitor television 104 ₁ is made.

On the other hand, if the room unit number and the own station number do not match, the changeover switches 205 and 206 are connected to the data identification circuit 204 in a state opposite to that shown in FIG. Therefore, the collective entrance slave unit 10
Since 1 is not connected to the room unit 106 ₁ , no voice call is made. Moreover, the room 106 _first distributing circuit 201
Although the video signal is supplied via the, the monitor power signal is not supplied, so that the video is not displayed.

In this case, the video signal is distributed to the distribution circuit 201, the compensation circuit 202, the limiter circuit 203 and the parallel cable 1
09 ₄ via an output to the next stage of the adapter 103 _2. The audio signal is supplied to the changeover switch 206 and the parallel cable 108
₄ through the output to the adapter 103 _2. The data signal is directly passed through the parallel cable 108 ₄ to the adapter 103 _2.
Is output to The monitor power signal is supplied to the adapter 10 via the changeover switch 205 and the parallel cable 108 _4.
3 is output _2.

[0022] In the adapter 103 _2, compared with the channel selection number and own number data signal represents, performs the same operation according to whether a match. Similarly, when the channel selection number and the own station number do not match, the same operation is performed up to the adapter 103 _n , and the room units 106 _{1 to} 106 _n selected by the intercom 101 and the collective entrance slave unit 101 A call is made and a monitor is made between them.

FIG. 3 is a circuit diagram showing one embodiment of the distribution circuit 201. In FIG. 3, a distribution circuit 201 includes a balanced input section 304 to which a video signal is input, a first balanced output section 305 that distributes the video signal input to the balanced input section to demodulation means, and a high frequency compensation means. And a second balanced output section 306 that distributes the video signal to the next stage adapter.
An output 1 and an output 2 which are supplied to and distributed to 303 are obtained.

FIG. 4 is a circuit diagram showing another embodiment of the distribution circuit 201. In FIG. 4, a distribution circuit 201 includes a balanced input unit 404 to which a video signal is input, a first balanced output unit 405 that distributes the video signal input to the balanced input unit to a demodulation unit, and a high frequency compensation unit. And a second balanced output unit 406 for distributing the video signal to the next-stage adapter. The video signal is output to the transformers 401 and 402, and the branched output 1 and output 2 are obtained.

In this embodiment, since the distribution circuit 201 shown in FIGS. 3 and 4 is used, insulation between the input side and the output side can be achieved, and one of the outputs becomes open or short-circuited. Even if a failure or the like occurs, there is an effect that the other output is not affected. FIG. 5 shows the compensation circuit 2
A diagram for explaining the operation of the 02 is a spectrum waveform diagram depicting a video signal about the carrier frequency F _c.

A transmission line using a parallel cable has a characteristic that is proportional to f- ^{1 / 2 due} to a skin effect when transmitting a high-frequency signal.
As shown in FIG. 5A, the high frequencies are attenuated. In order to compensate for this, by providing a compensation circuit having an amplification characteristic that raises the high-frequency characteristic, the high-frequency characteristic is compensated as shown in FIG. ing.

The limiter amplifier circuit 203 is provided for transmitting a video signal at an appropriate level. Even if the level of the video signal fluctuates, the limiter amplifying circuit 203 maintains the video signal at a constant level so that an appropriate video signal can be obtained. A signal can be transmitted. Further, it is possible to remove the AM component generated due to the characteristics of the transmission path, and it is possible to use an IF amplifier circuit or the like used in FM radio or the like.

In the embodiment described above, all the adapters 1
03 ₁ to compensation circuit 202 to 103 _n and the limiter amplifier circuit 203 is provided, but for example, such as provided for each 200 meters, it can be changed depending on the characteristics of the parallel cable. Further, the audio signal and the video signal are transmitted through different parallel cables, however, the video signal and the audio signal may be multiplex-transmitted to the same parallel cable by using the baseband transmission of the audio. .

Although the distribution circuit shown in FIGS. 3 and 4 has been described as a distribution circuit, balanced input / output is possible, and insulation between output 1 and output 2 and insulation between output 1 and output 2 and input are possible. Can be used in other circuits as well. Further, although the parallel cable is used as the telephone communication line, a balanced line such as a twisted pair cable other than an unbalanced line (such as a coaxial cable) can be used.

As described above, according to this embodiment, the video is transmitted using the FM-modulated video signal despite the use of a parallel cable other than the coaxial cable or a cable such as a twisted pair cable. As a result, the image quality is not degraded, and the wiring processing can be easily performed. In addition, since the video signal is supplied from the distributor to the next-stage adapter circuit via the amplifier circuit for high-frequency compensation, high-frequency characteristics are compensated, and long-distance transmission is possible without deteriorating image quality. And the like.

[0031]

According to the present invention, since the video signal is modulated and transmitted, the image quality is not degraded even when transmitted by the parallel cable, and the wiring processing can be easily performed. . Further, since the video signal is supplied from the distributor to the next-stage adapter via the compensating means, there is an effect that the image quality is not deteriorated even if the transmission distance becomes long.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram of an adapter used in the present invention.

FIG. 3 is a block diagram of a distribution circuit used in the present invention.

FIG. 4 is a block diagram of a distribution circuit used in the present invention.

FIG. 5 is a waveform chart for explaining the operation of the present invention.

FIG. 6 is a block diagram of a conventional TV door phone apparatus.

FIG. 7 is a block diagram of an adapter used for a conventional TV door phone device.

[Explanation of symbols]

 101: collective entrance terminal 103: adapter 104: monitor television 105: intercom 106: living room 109: parallel cable 110: modulation circuit 111 as modulation means 111: Demodulation circuit 201 as demodulation means 201 Divider 202 High-frequency compensation circuit as high-frequency compensation means 304, 404 Balanced input section 305, 405 First balanced output section 306, 406 ... Second balanced output section

Claims (1)

(57) [Claims] 1. A collective entrance terminal (10) having a television camera.
1) and an adapter (103) for each of the collective entrance slaves
A plurality of room units (106) connected via
In a television door phone apparatus, a telephone call is made between the collective entrance unit and the selected living room unit, and a monitor TV (104) of the indoor unit monitors the video signal transmitted from the collective entrance unit. A modulating means (110) for modulating a video signal from the collective entrance slave unit and outputting the modulated video signal to the adapter via a parallel cable (109); and the modulated video signal received from the adapter via the parallel cable. Demodulation means (111) for demodulating the video signal and outputting the demodulated video signal to the living room unit; a distributor (201) for distributing the modulated video signal from the modulation means to a next-stage adapter; High-frequency compensating means (20) for compensating and outputting to the next-stage adapter
2) wherein the distributor comprises a balanced input section (304, 404) to which the video signal is input, and a first balanced output for distributing the video signal input to the balanced input section to the demodulation means. Department (3
05, 405) and a second balanced output section (306, 40) distributed to the next-stage adapter via the high-frequency compensation means.
6) A television intercom apparatus comprising: