JP2782398B2 - Home bus system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a home bus system used for home use or the like.

[0002]

2. Description of the Related Art FIG. 5 shows the configuration of a conventional home bus system having a video door phone communication function. In FIG. 5, 101 is a camera intercom slave unit, 102 is a home bus controller, 103 is a telephone, 104 is a monitor TV unit, and an information outlet connected to each terminal has a control channel 105 with four twisted pair cables, Information channels 106, 107, 108;
A coaxial cable 109 is provided as an information channel for transmitting a video signal.

[0003] Next, the operation of the conventional video door phone communication function will be described. In FIG. 5, when the switch of the calling signal sending unit 110 of the camera intercom slave unit 101 is pressed and the incoming call detecting unit 111 of the home bus controller 102 is activated, the information is sent to the CPU 112, and the CPU 112 sends the information to the AMI interface circuit (I
A command is sent to the control channel 105 through the / F) 113. At the same time, the CPU 112 activates the intercom power supply circuit 114, and the camera intercom slave unit 101
The camera 115 and the modulation unit 116 are activated, and the modulation signal is input to the video signal demodulation unit 117 of the home bus controller 102. The video signal demodulated by the video signal demodulation unit 117 is transmitted to the monitor television unit 104 through the coaxial cable 109.

On the other hand, an AMI interface circuit (I / F) 118 of telephone set 103 receives a command for intercom reception from control channel 105 and causes ringing tone generation section 120 to transmit a ringing tone indicating that there is an intercom reception via CPU 119. . Also, the AMI interface circuit (I / F) 121 of the monitor television unit 104 similarly activates the video input unit 123 and the power supply unit 124 by the CPU 122 in response to a command from the home bus controller 102, and sends the signal to the cathode ray tube (CRT) 125. The video captured by the camera intercom slave unit 101 is output.

When the telephone 103 responds to the incoming call from the camera intercom slave unit 101, the CPU 1 of the telephone 103
19 allows the switching unit 126 to capture the information channel 108 and, at the same time, the AMI interface circuit 118
Sends a command to the effect that it has responded to the home bus controller 102 through the control channel 105. The CPU 112 of the home bus controller 102 thereby controls the switching unit 127 to link the communication path between the camera intercom slave unit 101 and the telephone 103 that has responded, thereby establishing a door phone call. At the same time, the video signal demodulator 117
Keeps transmitting the video signal to the coaxial cable 109 until the intercom call of the telephone 103 ends.

As described above, even in the above-described conventional home bus system having a TV door phone call function, the camera door phone slave unit 1 connected to the home bus controller 102 can be used.
01, telephone 103 and monitor television unit 104
This allows a door phone call to be made while checking the image of the visitor.

[0007]

However, in the above conventional home bus system, in addition to the wiring of the control channel and the information channel constituted by the four twisted pair cables 105 to 108, a coaxial cable is used for transmitting a video signal. There is a problem that the information channel by the cable 109 must be wired.

Further, since the home bus controller 102 includes a circuit for intercom communication, there is a problem that the wiring from the camera intercom slave unit 101 must be wired to the place where the home bus controller 102 is arranged. there were.

The present invention solves such a conventional problem. Wiring between a communication terminal device such as a home bus controller or a telephone and a transmitting / receiving terminal of a video signal can be performed only by an information channel of a twisted pair cable. The purpose is to provide an excellent home bus system.

Another object of the present invention is to provide a home bus system which does not require wiring from a camera intercom slave to a home bus controller.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a conventional voice call signal on one of information channels used for extension calls and intercom calls. A video signal from a door phone handset or the like is frequency-modulated at a frequency sufficiently higher than the frequency used for communication, and a video modulation signal is superimposed on the video signal to transmit and receive information to and from a terminal device.

[0012] The present invention also provides a camera intercom adapter capable of transmitting an image signal obtained by frequency-modulating an image signal picked up by a camera intercom slave unit on an information channel and enabling a door phone call with a call terminal via the information channel. It is provided.

[0013]

The present invention has the following functions by the above-described configuration. That is, by superimposing a voice communication signal and a frequency-modulated video signal on one information channel, a video transmitting / receiving terminal can be connected without using a coaxial cable dedicated to the video signal, and only a twisted pair cable can be used. With this wiring, a home bus system having a video transmission / reception function can be configured.

According to the present invention, since the camera door phone adapter is provided, the wiring from the camera door phone slave unit does not need to be routed to the home bus controller, and the camera door phone adapter is installed near the entrance where the camera door phone slave unit is installed. Thereby, the wiring can be shortened and the wiring cost can be reduced.

[0015]

FIG. 1 shows a system configuration of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a camera door phone handset, 2 denotes a camera door phone adapter, 3 denotes a home bus controller, 4 denotes a telephone, 5 denotes a monitor TV unit, and 6 denotes a terminator. And a control channel 7 and information channels 8, 9, and 10 using four twisted pair cables. The terminator 6 is connected to the last end of the information channel 10 of the four twisted pair cables.

FIG. 2 is a block diagram showing a circuit configuration of the camera door phone slave unit 1 and the camera door phone adapter 2.
In the camera intercom slave unit 1, 11 is a camera, 12 is a frequency modulation unit, 13 is a capacitor, and 14 is a speaker (S
P) and 15 are a hybrid circuit (HYB), 16 is a choke, 17 is a microphone (MIC), 18 is a calling signal transmitting unit, and 19 is a power receiving circuit.

In the camera door phone adapter 2, 2
0 is an incoming call detector, 25 is an AMI interface circuit (I / F), 26 is a CPU, 31 is a call interface circuit (I / F), 32 is a choke, 33 is an FM automatic gain control circuit (AGC), and 34 is a capacitor. It is.

FIG. 3 is a block diagram showing a circuit configuration of the home bus controller 3 and the telephone 4. In the home bus controller 3, 35 is an office line interface circuit (I / F), 36 is an AMI interface circuit (I / F), 37 is an extension power supply circuit, 38 is a CPU, 39
Is a power supply circuit, 40 is a switching unit, and 41 is a choke.

In the telephone 4, reference numeral 42 denotes a chalk;
Is a capacitor, 44 is a choke, 45 is a power receiving circuit, 46
Is an AMI interface circuit (I / F), 47 is a switching unit, 48 is a CPU, 49 is a ringing tone generating unit, 50 is a talking unit, 51 is a receiving unit (R), and 52 is a transmitting unit (T).

FIG. 4 is a block diagram showing a circuit configuration of the monitor television unit 5, the video demodulator 53, the video modulator 54, and the terminator 6. In the monitor television unit 5, 55 is a choke, 56 and 57 are capacitors, 58 is a power receiving circuit, and 59 is an AMI interface circuit (I /
F), 60 is a video demodulation unit, 61 is a CPU, 62 is a cathode ray tube (CRT), and 63 is a power supply circuit.

In the video demodulation device 53, 64 is a choke, 65 and 66 are capacitors, 67 is a power receiving circuit, 68 is an AMI interface circuit (I / F), and 69 is a CP.
U and 70 are a video demodulation unit, and 71 is a video output unit.

In the video modulator 54, 72 is a choke, 73 and 74 are capacitors, 75 is a power receiving circuit, 76 is an AMI interface circuit (I / F), 77 is a video modulator, 78 is a CPU, and 79 is a video input unit. It is.

In the terminator 6, reference numeral 80 denotes a capacitor;
1 is a resistor, and 82 is a capacitor.

The condenser 34 of the camera doorphone adapter 2 and the condenser 57 of the monitor television unit 5
Is a capacitor for giving a low impedance only to the video signal, and the input of the video demodulation unit 60 is terminated with an impedance higher than the characteristic impedance of the cable at the modulation signal frequency. The choke 32 of the camera door phone adapter 2, the choke 41 of the home bus controller 3, and the choke 44 of the telephone 4
It is a choke for giving only a call signal a low impedance.

In the terminator 6, the modulation signal is terminated by capacitors 80 and 82 having a low impedance only at the modulation signal frequency and a resistor 81 having a resistance equal to the characteristic impedance of the cable. When a modulation signal transmission circuit such as the camera door phone adapter 2 is connected at an intermediate point instead of the far end of the bus line,
By connecting terminators to both ends of the bus line, signal reflection can be prevented.

Next, the operation of the video door phone communication function in the above embodiment will be described. In FIG. 2, the switch of the call signal transmitting unit 18 of the camera intercom slave 1 is pressed, and the incoming call detection unit 20 of the camera intercom adapter 2 is pressed.
Is started, the information is sent to the CPU 26, and the CPU 26
26 sends a command to the control channel 7 through the AMI interface circuit 25. At the same time, the CPU 26 activates the intercom power supply circuit 23, activates the camera 11 and the frequency modulation unit 12 of the camera intercom slave unit 1, and inputs a modulation signal to the FM automatic gain control circuit 33 of the camera intercom adapter 2. FM automatic gain control circuit 3
The video modulation signal amplified to a constant amplitude level by 3 is sent to the information channel 10 through the capacitor 34.

On the other hand, in FIG. 3, the AMI interface circuit 46 of the telephone 4 receives the intercom call command from the control channel 7, and causes the ringing tone generator 49 to output a ringing sound indicating that the intercom call has been received through the CPU 48. In FIG. 4, the monitor TV unit 5
The AMI interface circuit 59 similarly activates the video demodulation unit 60 and the power receiving circuit 58 by the CPU 61 in response to a command from the camera door phone adapter 2,
The video modulation signal is input from the information channel 10 to the video signal demodulation unit 60 via the capacitor 57, and the video captured by the camera intercom slave unit 1 is output to the CRT 62.

When the telephone 4 responds to the incoming call of the camera intercom slave 1, the CPU 48 of the telephone 4 sends a command to the effect that the telephone 4 has responded to the home bus controller 3 through the control channel 7 via the AMI interface circuit 46. The CPU 38 of the home bus controller 3 links the communication path between the camera intercom adapter 2 and the telephone 4 that has responded, thereby establishing the intercom call. At the same time, the camera door phone adapter 2 FM
The automatic gain control circuit 33 continues to transmit the video signal to the information channel 10 until the telephone call of the telephone 4 ends.

In the video demodulation device 53 of FIG. 4, similarly to the monitor television unit 5, the video demodulation signal is received from the information channel 10 under the control of the home bus controller 3, and the signal demodulated by the video demodulation unit 70 is transmitted. The image is output to an image display device such as a CRT monitor connected to the outside through the image output unit 71.

In the video modulator 54, a video signal picked up by an external camera or the like is input from a video input unit 79, modulated by the video modulation unit 77, and transmitted in the same manner as the camera intercom adapter 2. The frequency-modulated signal is transmitted to the channel 10.

[0031]

According to the present invention, as is apparent from the above embodiment, a voice communication signal and a video frequency-modulated at a frequency sufficiently higher than this are provided for a pair of information channels to which a home bus controller and various terminals are connected. By superimposing the signal, it is possible to perform the wiring between the home bus controller and the camera door phone adapter, the telephone, the monitor TV unit, the video modulation device, and the video demodulation device connected as the terminal only by the twisted pair cable. Have.

The camera intercom adapter has a function of transmitting a video signal obtained by frequency-modulating a video signal picked up by a camera intercom slave unit on the information channel and having a function of performing intercom communication with a call terminal via the information channel. By doing so, it is possible to install a camera door phone adapter connected by a bus for the home bus near the entrance where the camera door phone slave is installed, without routing the wiring from the camera door phone slave to the home bus controller, There is an effect that the wiring of the camera intercom can be shortened and the wiring cost can be reduced.

The use of the video modulation device has the effect that video information input not only by the camera intercom but also by any device can be received by the video receiving terminal in the home bus system.

The use of the video demodulator has the effect that a video signal can be output not only to a monitor television unit but also to any device such as a television or a video deck having a general video input terminal.

[Brief description of the drawings]

FIG. 1 is a block diagram of an entire home bus system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a camera door phone slave and a camera door phone adapter according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a circuit configuration of a home bus controller and a telephone according to one embodiment of the present invention.

FIG. 4 is a block diagram showing a circuit configuration of a monitor television unit, a video demodulation device, a video modulation device, and a terminator according to an embodiment of the present invention.

FIG. 5 is a block diagram of the entire conventional home bus system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Camera intercom slave unit 2 Camera intercom adapter 3 Home bus controller 4 Telephone 5 Monitor television unit 6 Terminator 7 Control channel 8 Information channel 9 Information channel 10 Information channel 11 Camera 12 Frequency modulation unit 13, 22, 34, 43, 56, 57, 65, 66, 7
3, 74, 80, 82 capacitor 14 Speaker (SP) 15, 29, 30 Hybrid circuit (HYB) 16, 21, 32, 41, 42, 44, 55, 64, 7
2 Choke 17 Microphone (MIC) 18 Call signal transmitting unit 19, 24, 45, 58, 67, 75 Power receiving circuit 20 Incoming detecting unit 23 Doorphone power supply circuit 25, 36, 46, 59, 68, 76 AMI interface circuit (I / F) 26, 38, 48, 61, 69, 78 CPU 27, 28 Amplifier (AMP) 31 Communication interface circuit (I / F) 33 FM automatic gain control circuit (AGC) 35 Local line interface circuit (I / F) 37 Extension power supply circuit 39 Power supply circuit 40, 47 Switching unit 49 Ring tone generation unit 50 Talk unit 51 Receiver unit (R) 52 Transmission unit (T) 53 Video demodulator 54 Video modulator 60, 70 Video demodulator 62 Cathode ray tube ( (CRT) 63 power supply circuit 71 video output unit 77 video modulation unit 79 video input unit 81 resistance

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04Q 9/00-9/16

Claims (4)

(57) [Claims] 1. A video signal, which is frequency-modulated at a frequency sufficiently higher than a voice communication signal, on an information channel formed by a pair of twisted pair cables connecting a home bus controller and a plurality of terminal devices together with a voice communication signal. Means for superimposing and transmitting; a plurality of video signal receiving terminal means for adjusting the input impedance to an impedance higher than the characteristic impedance of the twisted pair cable at the carrier frequency of the frequency-modulated video signal; and the frequency-modulated video signal. And a terminator matched to the characteristic impedance of the twisted pair cable at the carrier frequency. 2. A camera intercom slave unit is connected to perform a voice call and a video signal with the camera intercom slave unit, and a video signal obtained by frequency-modulating a video signal captured by the camera intercom slave unit on an information channel. 2. The home bus system according to claim 1, further comprising a camera doorphone adapter for transmitting and performing a doorphone call with the call terminal via the information channel. 3. A video modulator for frequency-modulating and transmitting a video signal input from a video input terminal on an information channel formed by a pair of twisted pair cables connected to a home bus controller and a plurality of terminal devices via a bus. The home bus system according to claim 1 or 2, further comprising: 4. A video signal to which a video modulation signal transmitted over an information channel by a pair of twisted pair cables connecting a home bus controller and a plurality of terminal devices via a bus is input, and the video modulation signal is demodulated and output. The home bus system according to any one of claims 1 to 3, further comprising a demodulation device.