JPH0583611A - Video camera system - Google Patents

Abstract

PURPOSE:To transmit sound information at a remote place and that on plural channels with one cable by amplifying a radio frequency signal by receiving with an antenna, synthesizing it with a video signal, and transmitting it to a demodulation unit via the cable. CONSTITUTION:An audio signal from an FM wireless mike, etc., installed at a place separated from a video camera 1 is received with the antenna 20, and after it is amplified by an amplifier 21, the video signal can be synthesized by a synthesis circuit 7. Thence, it is transmitted to the demodulation unit 10 via the cable 9, and is outputted from output terminals 13, 14 as the audio signal or the video signal. Also, the signal can be transmitted with an image signal with one cable without generating a trouble by setting frequencies differently from each other even when plural wireless mikes are installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal multiplex type video camera system in which an antenna is attached to a video camera to receive and transmit an electric field in the air.

[0002]

2. Description of the Related Art FIG. 7 shows an example of a conventional video system, in which an audio signal from a microphone section 3 is superimposed on a video signal. That is, the video camera 1 includes a lens unit 2, an image pickup tube or CCD 4 for converting light into an electric signal,
Also, the microphone unit 3 is integrated, the video signal obtained by converting the optical signal is amplified by the video amplifier 5, the audio output from the microphone unit 3 is amplified and modulated by the modulation circuit 6, and the audio signal is converted into the audio signal by the synthesis circuit 7. The video signals are combined.

When synthesizing, assuming that the signal band of the video signal is 0 to 5 MHz, the audio signal is 20 to 50 MHz.
It is sufficient to modulate to. The combined signal is input from a terminal 8 to a demodulation unit 10 such as a monitor TV via a cable 9, and is input to a video amplifier 11 and a demodulation circuit 12, respectively, and an audio output is obtained from an output terminal 13 of the demodulation circuit 12 to obtain a video amplifier. A video output is obtained from the output terminal 14 of 11.

[0004]

In the above-mentioned prior art, although it is convenient that the video signal and the audio signal can be combined and transmitted by one cable 9, the video camera 1 and the microphone section 3 are provided. Had to be attached together or connected via a cable, it was not possible to obtain audio information from a distant position, and it was not possible to use a microphone of several channels at a time. Further, there is a problem that the outputs of various sensors cannot be superimposed on the video cable and bidirectional communication of audio signals cannot be performed.

The present invention has been made to solve the above problems, and it is possible to transmit audio information of distant positions and audio information of a plurality of channels together with image information through a single cable, Another object of the present invention is to obtain a video camera system capable of radiating audio information inputted through a cable to the surroundings and transmitting outputs of various sensors through the cable.

[0006]

A video camera system according to the present invention includes an antenna for receiving an electric field in the air, that is, a modulated radio frequency signal, a first amplifier for amplifying a band of the received electric field, and this amplification. A synthesizing means for synthesizing the signal and the video signal is provided, and the output of the synthesizing means is supplied to the demodulation unit via a cable.

In the video camera system according to the present invention, a second amplifier for amplifying a modulated radio frequency signal input via a cable is provided in antiparallel with the first amplifier.

Further, the video camera system according to the present invention is provided with means for receiving the outputs of a plurality of sensors and converting them into a serial signal, and means for FM-modulating the serial signal. It is designed to be received by an antenna.

[0009]

In the present invention, the electric field in the air emitted from the FM wireless microphone or the like is received by the antenna, amplified, and transmitted by the cable together with the video signal.

Further, according to the present invention, the modulated radio frequency signal inputted through the cable is amplified by the second amplifier and radiated from the antenna to the surroundings.

Further, in the present invention, the outputs of the plurality of sensors are converted into a serial signal, and the serial signal is FM-modulated and received by the antenna.

[0012]

EXAMPLES Example 1. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of a video system according to the first embodiment, and an antenna 20 is built in or connected to the video camera 1. The relationship between the frequency band and the gain of the amplifier 21 connected to the antenna 20 is shown in FIG.
It has a certain amount of gain for frequencies greater than the video signal band 0-5 MHz. In FIG. 2, the frequency is 30 MHz or higher, but there is no limitation on the frequency and a narrow band as shown by the dotted line may be used.

In the above configuration, for example, when a commercially available FM wireless microphone is installed at a position distant from the video camera 1, the audio signal from this wireless microphone is received by the antenna 20, amplified by the amplifier 21, and then synthesized circuit 7. Is combined with the video signal at the cable 9
Is transmitted to the demodulation unit 10 via the output terminal 13,
It is output from 14 as an audio signal and a video signal.

Further, even if a plurality of wireless microphones are installed, they can be used without any trouble by making their frequencies different from each other, and a commercially available FM radio can be used instead of the demodulation circuit 12 in the demodulation unit 10. Can be received. Furthermore, the outputs of various sensors such as a sensor that reacts when a person approaches the periphery of the video camera 1 and a sensor that responds when a door is opened are FM-modulated to perform FM modulation.
To the demodulation unit 10.

Example 2. FIG. 3 shows a configuration of a video system according to a second embodiment of the present invention. An amplifier 2 is provided between the antenna 20 and the synthesizing circuit 7 so that bidirectional amplification can be performed.
1, 22 are provided in anti-parallel, and the demodulation unit 10 has an audio input terminal 27, a modulation circuit 23, and an antenna 2
4, and amplifiers 25 and 26 are provided.

In the above structure, in addition to the function of the first embodiment, the audio signal input from the input terminal 27 is modulated by the modulation circuit 23, superposed on the cable 9 and transmitted to the video camera 1, and amplified by the amplifier 22. It is radiated from the antenna 20 to the vicinity of the video camera 1.
Therefore, if there is an antenna and a demodulation circuit near the video camera 1, that is, if there is a receiver (radio, transceiver), reception is possible. Thus, in the second embodiment, bidirectional communication is possible.

Further, by providing the demodulation unit 10 with the antenna 24 and the amplifiers 25 and 26, it becomes possible to transmit and receive a wireless telephone or the like between the vicinity of the video camera 1 and the vicinity of the demodulation unit 10. This is possible even at a distance where the wireless telephone cannot transmit / receive, or even in a place where radio waves do not reach, such as in a building. That is, communication becomes possible by superimposing radio waves on the video cable 9.

Example 3. FIG. 4 shows the structure of a sensor output transmitter of a video camera system according to a third embodiment of the present invention, and 30 is a human sensor for detecting a human by infrared rays or the like.
Reference numeral 1 is a door sensor that detects opening and closing of a door, and 32 is an optical sensor that detects light. The outputs of the sensors 30 to 32 are converted from parallel information to serial information by a processing circuit 40 including a microcomputer or a logic circuit. The FM modulation circuit 41 performs FM modulation, the amplifier 42 amplifies the signal, and the antenna 4
Radiated from 3 into the air.

FIG. 5 shows an example in which the processing circuit 40 is composed of a parallel input serial output shift register.
68 are parallel inputs, 69 are serial inputs, 70 is a clock input, and 71 is a serial output.

FIG. 6 shows a configuration of a video system corresponding to FIG. 4, 50 is a serial input / parallel output serial / parallel conversion circuit, 51 to 53 are output terminals, and the signal radiated from the antenna 43 of FIG. Received by the antenna 20 and input to the demodulation circuit 12 via the cable 9,
The output is converted into parallel output by the serial / parallel conversion circuit 50, and output from the output terminals 51 to 53 to the sensors 30 to 32.
Is output.

When the processing circuit 40 is composed of a microcomputer, it is possible to convert analog information such as temperature and humidity into digital information for serialization, and FIG.
It is also possible to convert the audio output from the output terminal 13 of the above into the original analog information for processing by connecting it to the microcomputer.

[0022]

As described above, according to the present invention, the electric field in the air emitted from the FM wireless microphone or the like is received by the antenna and transmitted by the cable together with the video signal. The audio information of the channel can be transmitted together with the image information on a single cable. Further, since the voice information can be transmitted bidirectionally, the voice information input via the cable can be transmitted to the surroundings. Furthermore, the outputs of various sensors can also be transmitted via a cable.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a video system according to a first embodiment of the present invention.

FIG. 2 is a frequency-gain characteristic diagram of the amplifier according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram of a video system according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a sensor output transmission unit of a video camera system according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a processing circuit according to a third embodiment of the present invention.

FIG. 6 is a block diagram of a video system according to a third embodiment of the present invention.

FIG. 7 is a block diagram of a conventional video system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 video camera 2 lens part 4 image pick-up tube 7 synthetic | combination circuit 9 cable 10 demodulation unit 20,43 antenna 21,22 amplifier 30-32 sensor 40 processing circuit 41 FM modulation circuit

Claims (3)

[Claims] 1. A means for converting an optical video signal into a video signal, an antenna for receiving an electric field in the air, that is, a modulated radio frequency signal, a first amplifier for amplifying a band of the received electric field, and this amplifier. A video camera system comprising: a synthesizing unit for synthesizing the generated signal and a video signal, and supplying the output of the synthesizing unit to a demodulation unit via a cable. 2. The video camera system according to claim 1, further comprising a second amplifier provided in antiparallel with the first amplifier for amplifying a modulated radio frequency signal input via a cable. 3. An output of a plurality of sensors is inputted, a means for converting parallel information of these to serial information, and a means for FM modulating this serial information are provided, and the FM modulated signal is received by the antenna. The video camera system according to claim 1, wherein the video camera system is configured as described above.