KR0183639B1 - Two line video doorphone apparatus - Google Patents

Two line video doorphone apparatus Download PDF

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Publication number
KR0183639B1
KR0183639B1 KR1019930014458A KR930014458A KR0183639B1 KR 0183639 B1 KR0183639 B1 KR 0183639B1 KR 1019930014458 A KR1019930014458 A KR 1019930014458A KR 930014458 A KR930014458 A KR 930014458A KR 0183639 B1 KR0183639 B1 KR 0183639B1
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South Korea
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signal
voice
video
amplifying
circuit
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KR1019930014458A
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Korean (ko)
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KR950005046A (en
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서인석
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이대원
삼성항공산업주식회사
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/18—Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast
    • H04N7/183—Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast for receiving images from a single remote source
    • H04N7/186—Video door telephones
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
    • H04N5/60—Receiver circuitry for the reception of television signals according to analogue transmission standards for the sound signals

Abstract

본 발명은 2선식 비디오 도어폰장치에 관한 것으로 특히, 비디오신호는 FM변조하고, 음성신호는 무변조하여 직류전원에 다중화시켜서 송수신하는 것을 특징으로 한다. 따라서, 본 발명은 회로구성이 간단하며 깨끗한 화질을 볼 수 있다.The present invention relates to a two-wire video door phone apparatus, and more particularly to a two-wire type video door phone apparatus, in which a video signal is FM-modulated and a voice signal is non-modulated and multiplexed to a DC power source for transmission and reception. Therefore, the present invention has a simple circuit configuration and a clear image quality.

Description

2선식 비디오 도어폰장치2-wire video door phone device

제1도 내지 제3도는 종래의 2선식 비디오 도어폰장치들을 나타낸 구성도.FIG. 1 is a block diagram of a conventional two-wire video door phone apparatus. FIG.

제4도 내지 제6도는 종래의 2선식 비디오 도어폰장치들의 영상 및 음성신호의 통신방식을 설명하기 위한 도면.FIGS. 4 to 6 are diagrams for explaining a communication method of video and audio signals of conventional 2-wire video door phone devices; FIG.

제7도는 본 발명에 의한 2선식 비디오 도어폰장치를 나타낸 구성도.FIG. 7 is a configuration diagram showing a two-wire video door phone apparatus according to the present invention; FIG.

제8도는 본 발명에 의한 2선식 비디오 도어폰장치의 영상 및 음성신호의 통신방식을 설명하기 위한 도면.FIG. 8 is a diagram for explaining a communication method of video and audio signals of a two-wire video door phone apparatus according to the present invention; FIG.

본 발명은 2선식 비디오 도어폰장치에 관한 것으로, 특히 회로구성이 간단하고 화면이 양호한 2선식 비디오 도어폰장치에 관한 것이다.The present invention relates to a two-wire video door phone device, and more particularly to a two-wire video door phone device having a simple circuit configuration and a good screen.

일반적으로, 비디오 도어폰장치는 방문자와 인터페이스를 위한 아웃도어세트와, 사용자와 인터페이스를 위한 인도어세트로 구성되어 있다. 아웃도어세트와 인도어세트는 전원공급과 쌍방통화를 위해 유선으로 연결되어 있다. 유선의 선수에 따라 4선식 또는 2선식등으로 구분하고 있으며, 최근에는 2선식이 주류를 이루고 있다. 2선식 비디오 도어폰장치는 2선의 전송선을 통해 아웃도어세트와 인도어세트간에 전원공급 및 영상/음성신호전송을 다중화하여 송수신하고 있다.Generally, a video door phone device is composed of an outdoor set for interfacing with a visitor, and an indoor set for interfacing with the user. Outdoor and Indian sets are wired for power supply and bilateral calls. It is classified into 4-wire type or 2-wire type according to the player of the wire, and recently, 2-wire type is mainstream. The two-wire video door phone device transmits and receives power supply and video / audio signal transmission between the outdoor set and the indoor unit via a two-wire transmission line.

제1도 및 제4도를 참조하면, 일본 아이폰(AIPHONE)사의 2선식 방식은 교류전원과, 영상신호를 FM변조한 신호와, 음성신호를 390KHz/455KHz대로 AM변조한 신호를 다중화시켜 송수신한다. 따라서 영상 및 음성신호를 각각 변조하고 복조하므로 회로구성이 복잡하고 각 대역별로 필터를 사용하여야 하므로 사용 부품수가 증대되는 결점이 있었다.Referring to FIGS. 1 and 4, AIPHONE's 2-wire system transmits and receives an AC power, a signal obtained by FM-modulating a video signal, and a signal obtained by AM-modulating a voice signal at 390 KHz / 455 KHz . Therefore, since the image and voice signals are modulated and demodulated, respectively, the circuit configuration is complicated and the filters must be used for each band.

제2도 및 제5도를 참조하면, 일본 마쯔시다(松下)사의 2선식 방식은 직류전원과, 무변조의 영상신호와, 음성신호를 AM변조한 신호를 다중화시켜 송수신한다. 따라서, 외부노이즈에 취약한 영상신호를 무변조로 전송하므로 화면이 선명치 못하며, 접지선과 신호선이 구분되는 유극성 방식이므로 전송선의 연결시 주의를 요하는 불편함이 있었다.Referring to FIG. 2 and FIG. 5, a two-wire system of Matsushita, Japan transmits and receives a DC power source, a non-modulated video signal, and a signal obtained by AM-modulating a voice signal. Therefore, since a video signal weak in external noise is transmitted in a non-modulated manner, the screen is not clear, and a grounding line and a signal line are distinguished from each other, so there is an inconvenience in connection of a transmission line.

제3도 및 제6도를 참조하면, 일본 샤프(SHARP)사의 2선식 방식은 직류전원과, 영상신호를 FM변조한 신호와, 음성신호를 220KHz/420KHz대로 FM변조한 신호를 다중화시켜 송수신한다. 따라서, 영상 및 음성신호를 각각 FM변조하고 복조하므로 회로구성이 복잡하고, 각 주파수대별로 필터를 사용해야 하므로 사용부품수가 증대하며 음성전송효율이 떨어지는 단점이 있으며, 직류전원이 유극성이므로 전송선의 접속시 주의를 요하는 불편함이 있었다.Referring to FIGS. 3 and 6, SHARP's two-wire system transmits and receives a direct current power, a signal obtained by FM-modulating a video signal, and a signal obtained by FM-modulating a voice signal at 220 KHz / 420 KHz . Therefore, since the video and audio signals are FM-modulated and demodulated respectively, the circuit configuration is complicated and filters are used for each frequency band. Therefore, the number of used parts is increased and the voice transmission efficiency is lowered. Since the DC power source is polarized, There was a discomfort requiring attention.

본 발명의 목적은 이상과 같은 종래기술의 문제점을 해결하기 위하여 회로구성이 간단한 2선식 비디오 도어폰장치를 제공하는 데 있다.SUMMARY OF THE INVENTION It is an object of the present invention to provide a two-wire video door phone apparatus having a simple circuit structure in order to solve the problems of the related art.

본 발명의 다른 목적은 무극성의 2선식 비디오 도어폰장치를 제공하는 데 있다.Another object of the present invention is to provide a non-polarized two-wire video door phone apparatus.

상기 목적들을 달성하기 위하여 본 발명의 장치는 아웃도어세트와 인도어세트를 전송선으로 접속하고 영상, 음성 및 전원을 다중화하여 전송하는 2선식 비디오 도어폰장치에 있어서, 비디오카메라를 통해 픽업된 영상신호를 FM변조하고 FM변조된 수 MHz대의 고주파신호를 고주파필터를 통해 상기 전송선에 결합하며, 마이크로폰을 통해 픽업된 음성신호를 증폭해서 음성분리수단을 통해 직류전원에 중첩하고, 음성신호가 중첩된 직류전원을 무극성수단 및 저주파필터를 통해 상기 전송선에 결합하며, 상기 음성분리수단을 통해 분리된 음성신호를 증폭해서 스피커를 통해 음성출력하기 위한 아웃도어세트와, 상기 전송선과 결합된 고주파필터를 통해 수신된 고주파신호로부터 영상신호를 검출해서 CRT스크린상에 표시하며, 상기 전송선과 결합된 저주파필터를 통해 직류전원에 중첩된 음성신호를 분리해서 증폭하여 스피커를 통해 음성출력하고, 마이크로폰을 통해 픽업된 음성신호를 증폭해서 직류전원에 중첩시켜 전송하는 인도어세트를 구비하는 것을 특징으로 한다.In order to achieve the above-mentioned objects, the present invention provides a two-wire video door phone device for connecting an outdoor set and an indoor set by a transmission line and multiplexing video, audio and power, and transmitting the video signal picked up by the video camera, Frequency-modulated high-frequency signal of several MHz band is coupled to the transmission line through a high-frequency filter, the voice signal picked up through the microphone is amplified and superimposed on the DC power source through the voice separating means, An outdoor set coupled to the transmission line through a non-polar means and a low-pass filter, for amplifying a voice signal separated through the voice separation means and outputting voice through a speaker, A video signal is detected from a high frequency signal and displayed on a CRT screen, and a low frequency And an indoor unit set for separating and amplifying the voice signal superimposed on the DC power source through the filter and outputting the voice through the speaker and amplifying the voice signal picked up through the microphone and superimposing the amplified voice signal on the DC power source.

이하 첨부한 도면을 참조하여 본 발명을 보다 상세히 설명하고자 한다.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention.

제7도를 참조하면, 본 발명에 의한 2선식 비디오 도어폰장치는 아웃도어세트(ODS)와 인도어세트(IDS)를 2선의 전송라인(L1,L2)으로 접속한다. 아웃도어세트(ODS)는 도어카메라(C1), 영상신호변조회로(C2), 호출신호발생회로(C3), 호출신호출력수단(C4), 라인트랜스(C5), 임피던스매칭회로(C6) 및 고주파필터(C7)를 구비한 영상송신부(10)를 가진다. 영상송신부(10)는 방문자 또는 도어 바깥쪽의 영상을 도어카메라(C1)를 통해 픽업하고, 픽업된 영상신호를 영상신호변조회로(C2)를 통해 4MHz의 밴드폭을 가지는 3.5MHz대의 FM변조신호를 출력하고, 변조된 신호를 라인트랜스(C5), 임피던스매칭회로(C6) 및 고주파필터(C7)를 통해 전송라인(L1,L2)에 인가한다. 호출신호발생회로(C3)를 호출키작동에 따라 호출신호를 발생하고 발생된 호출신호는 호출신호출력수단(C4)을 통해 라인트랜스(C5)에 인가된다.Referring to FIG. 7, a two-wire video door phone apparatus according to the present invention connects an outdoor set ODS and an indoor unit IDS with two-line transmission lines L 1 and L 2 . The outdoor set ODS includes a door camera C 1 , a video signal modulation circuit C 2 , a call signal generation circuit C 3 , a call signal output means C 4 , a line transformer C 5 , And a video transmitter 10 including a circuit C 6 and a high-frequency filter C 7 . The image transmitter 10 picks up an image of a visitor or a door outside through the door camera C 1 and outputs the picked up image signal to a 3.5 MHz band FM having a bandwidth of 4 MHz through a video signal modulation circuit C 2 And applies the modulated signal to the transmission lines L 1 and L 2 through the line transformer C 5 , the impedance matching circuit C 6 , and the high-frequency filter C 7 . The call signal generating circuit C 3 generates a call signal according to the call key operation and the generated call signal is applied to the line transformer C 5 via the call signal output means C 4 .

아웃도어세트(ODS)는 저주파필터(C8), 무극성회로(C8), 음성신호분리회로(C10), 음성신호반전회로(C11), 증폭회로(C12), 스피커(C13), 마이크로폰(C1 4) 및 증폭회로(C15)를 구비한 음성송수신부(20)를 가진다. 음성송수신부(20)는 음성수신시에는, 전송선(L1,L2)에 접속된 저주파필터(C8)를 통해서 FM변조된 영상고주파신호는 차단하고 20KHz이하의 음성신호와 직류전원을 통과하고, 무극성회로(C8)를 통해 직류전원을 극성화시키고, 극성화된 직류전원에 중첩된 음성신호를 음성신호분리회로(C10)를 통해 분리해내고 분리된 음성신호는 음성신호반전회로(C11)를 통해 증폭회로(C12)에 공급하고, 증폭된 음성신호는 스피커(C13)를 통해 음성출력한다.The outdoor set ODS includes a low frequency filter C 8 , a non-polar circuit C 8 , a voice signal separation circuit C 10 , a voice signal inversion circuit C 11 , an amplification circuit C 12 , a speaker C 13 ), and has a microphone (C 1 4) and an amplifying circuit (voice transmitting and receiving section 20 with the C 15). The voice transmission / reception unit 20 blocks the FM-modulated image high-frequency signal through the low-frequency filter C 8 connected to the transmission lines L 1 and L 2 and transmits the audio signal of 20 KHz or less and the DC power source The polarity of the DC power source is made via the non-polar circuit C 8 , the voice signal superimposed on the polarized DC power source is separated through the voice signal separation circuit C 10 , the audio signal supplied to the amplifier circuit (12 C) through (C 11), amplifies and outputs audio through a speaker (C 13).

또한, 음성송신시에는, 마이크로폰(C14)을 통해 픽업된 음성신호를 증폭회로(C15)로 증폭하고, 증폭된 음성신호는 음성분리회로(C10)를 통해 직류전원에 중첩되어 무극성회로(C9) 및 저주파필터(C8)를 거쳐서 전송선(L1,L2)에 제공된다. 이때, 송신되는 음성신호는 음성신호반전회로(C11)에 의해 차단되므로 스피커(C13)로 출력되는 것이 방지된다.At the time of voice transmission, it is amplified by the microphone (C 14) of the audio signal amplifier circuit (C 15) picked up through the, and the amplified audio signal is superimposed on the direct-current power supply via the audio separation circuit (C 10) non-polar circuit Is provided to the transmission lines (L 1 , L 2 ) via a low-pass filter (C 9 ) and a low-frequency filter (C 8 ). At this time, the audio signal to be transmitted is prevented because it is blocked by the speech signal inversion circuit (C 11) is output to the speaker (C 13).

전원변환회로(C16)는 무극성회로(C8)를 통해 극성화된 직류전원을 입력해서 아웃도어세트(ODS)의 각 회로부에 필요한 직류구동전압을 발생하여 공급한다.Power converter circuit (C 16) are supplied to the input DC power source through the polarized non-polar circuit (C 8) generates a direct current driving voltage required for each circuit of the set outdoor (ODS).

따라서, 아웃도어세트(ODS)는 전송선(L1,L2)의 접속시에 L1과 L2가 바뀌어 접속되더라도 무극성회로(C9)에 의해 극성을 주의할 필요가 없다.Accordingly, the outdoor set (ODS) is a transmission line (L 1, L 2) during connection, even if the L 1 and L 2 connected to a change in it is not necessary to note the polarity by the polarity-circuit (C 9).

인도어세트(IDS)는 CRT(M1), CRT제어회로(M2), 영상신호복조회로(M3), RF신호결합수단(M4), 라인트랜스(M5), 임피던스매칭회로(M6) 및 고주파필터(M7)를 구비한 영상수신부(30)를 가진다. 영상수신부(30)는 전송선(L1,L2)에 접속된 고주파필터(M7)를 통해 직류 및 저주파신호는 차단하고 FM변조된 영상고주파신호만을 통과시키고, 임피던스매칭회로(M6), 라인트랜스(M5) 및 RF신호결합수단(M4)를 통해 수신된 영상고주파신호를 영상신호복조회로(M3)를 통해 복조 및 검파해서 영상신호를 검출하고, 검출된 영상신호를 CRT제어회로(M2)를 통해 CRT(M1) 스크린상에 영상표시한다.The IDS includes a CRT (M 1 ), a CRT control circuit M 2 , an image signal inquiry path M 3 , an RF signal coupling means M 4 , a line transformer M 5 , an impedance matching circuit M 6) and has an image receiving unit 30 is equipped with a high-frequency filter (7 M). The image receiving unit 30 cuts off the direct current and the low frequency signals through the high frequency filter M 7 connected to the transmission lines L 1 and L 2 and allows only the image modulated high frequency signal to pass therethrough and the impedance matching circuits M 6 , The image high frequency signal received through the line transformer M 5 and the RF signal combining means M 4 is demodulated and detected through the image signal correlation inquiry M 3 to detect the image signal, the image displayed on the screen CRT (M 1) via a circuit (M 2).

인도어세트(IDS)는 저주파필터(M8), 음성신호결합수단(M8), 증폭회로(M10), 스피커(M11), 축음용수단(M12), 증폭회로(M13), 및 마이크로폰(M14)을 구비한 음성송수신부(40)를 가진다. 음성송수신부(40)는, 음성수신시에는, 저주파필터(M8)를 통해 통과된 음성신호를 음성신호결합수단(M9)를 통해 증폭회로(M10)에 입력하고 증폭회로(M10)에서 증폭된 음성신호를 스피커(M11)를 통해 음성출력한다. 송신시에는, 마이크로폰(M14)을 통해 픽업된 음성신호를 증폭회로(M13)로 증폭해서 축음용수단(M12), 음성신호결합수단(M8) 및 저주파필터(M8)를 거쳐서 전송선(L2)에 제공한다.Indian set (IDS) is a low pass filter (M 8), audio signal combining means (M 8), an amplifier circuit (M 10), the speaker (M 11), the axis drinking means (M 12), an amplifier circuit (M 13), and it has a microphone speech transmitting and receiving unit (40) having a (M 14). When the voice transmission and reception unit 40, a voice is received, the voice signals pass through the low pass filter (M 8) from the audio signal combining means (M 9) input to the amplifier circuit (M 10) and an amplifier circuit (M 10 ) for the amplified sound signal to the sound output through the speaker (11 M) at. At the time of transmission, it is amplified by the microphone (M 14) the amplifier circuit (M 13) a pick-up audio signal through via a shaft drinking means (M 12), a voice signal combining means (M 8) and a low pass filter (M 8) To the transmission line L 2 .

인도어세트(IDS)는 음성신호저지회로(M15) 및 전원변환회로(M16)를 가지는 전원부(50)를 가진다. 전원부(50)는 직류전원을 입력해서 소정직류전원으로 변환하고 변환된 직류전원을 음성신호저지회로(M15) 및 저주파필터(M8)를 거쳐서 전송선(L1,L2)에 인가한다. 여기서, 음성신호저지회로(M16)는 송수신되는 음성신호가 전원부(50)쪽으로 인가되는 것을 차단한다.Indian set (IDS) has a power unit 50 having an audio signal blocking circuit (15 M) and the power converter circuit (M 16). The power supply unit 50 receives DC power and converts the DC power into a predetermined DC power and applies the converted DC power to the transmission lines L 1 and L 2 via the voice signal blocking circuit M 15 and the low frequency filter M 8 . Here, the audio signal blocking circuit (16 M) will block the audio signals transmitted and received to be applied into the power source 50. The

이상과 같이 구성한 본 발명에서는 제8도에 도시한 바와 같이, 음성신호는 무변조로 송수신하고, 노이즈에 취약한 영상신호는 FM변조해서 송신함으로써 깨끗한 화면을 볼 수 있을 뿐만 아니라 영상신호만 변조하므로 회로구성을 간략화할 수 있다. 또한, 아웃도어세트는 무극성회로를 채용해서 전송선(L1,L2)과 연결시 극성에 주의할 필요없이 연결하면 되므로 접속시 편리성을 도모할 수 있다.In the present invention constructed as described above, as shown in FIG. 8, the audio signal is transmitted / received unmodulated, the video signal weak in noise is FM-modulated and transmitted, The configuration can be simplified. In addition, the outdoor set employs a non-polar circuit, so that it is possible to connect the transmission lines (L 1 , L 2 ) without the need of paying attention to polarity when connecting the transmission lines (L 1 , L 2 ).

Claims (1)

아웃도어세트와 인도어세트를 2선의 전송선으로 접속하고 영상, 음성 및 전원을 다중화하여 전송하는 2선식 비디오 도어폰장치에 있어서, 비디오카메라를 통해 픽업된 영상신호를 FM변조하고 FM변조된 수 MHz대의 고주파신호를 고주파필터를 통해 상기 전송선에 결합하며, 마이크로폰을 통해 픽업된 음성신호를 증폭해서 음성분리수단을 통해 직류전원에 중첩하고, 음성신호가 중첩된 직류전원을 무극성수단 및 저주파필터를 통해 상기 전송선에 결합하며, 상기 음성분리수단을 통해 분리된 음성신호를 증폭해서 스피커를 통해 음성출력하기 위한 아웃도어세트와, 상기 전송선과 결합된 고주파필터를 통해 수신된 고주파신호로부터 영상신호를 검출해서 CRT스크린상에 표시하며, 상기 전송선과 결합된 저주파필터를 통해 직류전원에 중첩된 음성신호를 분리해서 증폭하여 스피커를 통해 음성출력하고, 마이크로폰을 통해 픽업된 음성신호를 증폭해서 직류전원에 중첩시켜 전송하는 인도어세트를 구비하는 것을 특징으로 하는 2선식 비디오 도어폰장치.A two-wire video door phone device for connecting an outdoor set and an indoor set with a two-wire transmission line and multiplexing and transmitting video, audio and power, characterized in that the video signal picked up by the video camera is FM- A microphone for amplifying a voice signal picked up through a microphone, superimposing the voice signal on a DC power source through a voice separating means, and a DC power source for superimposing a voice signal on the signal through a non-polarizing means and a low- An outdoor unit coupled to a transmission line for amplifying a voice signal separated through the voice separation unit and outputting voice through a speaker; and a control unit for detecting a video signal from a high frequency signal received through a high frequency filter coupled to the transmission line, And displays a voice signal superimposed on the DC power through a low-pass filter coupled with the transmission line And an indoor set for amplifying the audio signal output from the speaker, amplifying the audio signal output from the speaker, amplifying the audio signal picked up through the microphone, and superimposing and amplifying the amplified audio signal on the DC power source.
KR1019930014458A 1993-07-28 1993-07-28 Two line video doorphone apparatus KR0183639B1 (en)

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KR100433656B1 (en) * 2002-05-31 2004-05-31 (주) 코콤 videophone
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