KR102185201B1 - System for compositely transmitting power and control signal using image signal line in CCTV(Closed Circuit Television) - Google Patents

Abstract

The present invention relates to a power and control signal superimposed transmission system using a video signal line in CCTV. The power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention includes a PoC camera module, transmits the video signal according to the driving of the camera module to the PoC receiver, and the PoC receiver detects the PoC transmitter. A PoC transmitter for outputting a clock signal to the PoC receiver; And a PoC receiver that applies power on the video signal line to superimpose transmission to the PoC transmitter, receives and processes the video signal transmitted from the PoC transmitter, and transmits a signal to control the camera module of the PoC transmitter to the PoC transmitter. In addition, the PoC receiving unit applies power on the video signal line and transmits a relatively low voltage as a voltage supplied to operate only the circuit that detects the PoC transmitting unit in superimposed transmission to the PoC transmitting unit, and from the PoC transmitting unit After detecting the clock signal of for a certain period of time, a relatively high voltage is transmitted.

Description

System for compositely transmitting power and control signal using image signal line in CCTV (Closed Circuit Television)}

The present invention relates to a power and control signal superimposed transmission system using video signal lines in CCTV, and more particularly, superimposing power and control signals using only video signal lines without installing separate power lines or control signal lines. By transmitting, it relates to a power and control signal superimposed transmission system using a video signal line in CCTV that can reduce the difficulty and cost associated with CCTV installation and camera setup.

In CCTV (Closed Circuit Television), PoC (Power over Coax) technology refers to a technology that transmits power, video and camera control signals to remote cameras and storage devices with one cable.

In an environment that does not support PoC, a video line and a power line are required to operate a remote camera. In addition, depending on the environment in which the camera is installed, there may be many difficulties in extending the power line, and in some cases, control such as setting change and position adjustment (PTZ) is required for the installed camera.

Due to the carelessness or error of users and installers at the CCTV installation site, there are cases in which a general camera that does not support PoC is installed or connected in an environment composed of PoC, or a general camera that has been installed (a camera that does not support PoC) is sometimes connected. In this case, the camera or built-in parts may be damaged by the PoC voltage, or even a fire may occur.

Due to the above-described risk factors, when using a product that normally uses PoC transmitter/receiver, be sure to install and use the same set of transmitter/receiver. Otherwise, PoC video transmitter (PoC A method of determining whether to apply power to the video transmission line is used by detecting and determining the connection of the power separation unit).

On the other hand, Korean Patent Publication No. 10-0950741 (Patent Document 1) discloses a "power superimposed image transmission system capable of stable power supply". Accordingly, a power superimposed image transmission system capable of stable power supply A coaxial cable that superimposes a signal, a video signal, and a control signal and transmits it through a single transmission line; A power transmitter for controlling an operation of a remote camera through the coaxial cable, receiving a photographed image signal, and transmitting a power signal through the coaxial cable; In a superimposed image transmission system including; a signal transmission unit for receiving a power signal and providing it to the camera and transmitting the image signal photographed from the camera to the power transmission unit through the coaxial cable, wherein the power transmission unit is periodically It transmits the spare power and drives the camera by transmitting the main power signal only when the ECHO signal by the transmitted spare power is returned, and transmits the video signal of the driven camera by superimposing it with the main power signal through the coaxial cable. The signal transmission unit is characterized in that it returns the promised ECHO signal to the power transmission unit through the coaxial cable when the spare power is input.

In the case of such patent document 1, I do not know if there is an advantage of detecting the line condition so that it can effectively respond to various causes of failure in a VP (power superimposed image transmission) system that can occur on a transmission line. There is a problem that is difficult to apply when a PoC-supported camera or a non-PoC-supported camera is used in a CCTV system, as no countermeasures for using supported cameras or non-PoC supported cameras are provided.

Korean Patent Publication No. 10-0950741 (announced on April 5, 2010)

The present invention was created in consideration of the above matters comprehensively, and by superimposing and transmitting power and control signals using only a video signal line without installing a separate power line or control signal line, CCTV installation and camera setting, etc. An object thereof is to provide a power and control signal superimposed transmission system using video signal lines in CCTV that can reduce the accompanying difficulties and costs.

Another object of the present invention is in a CCTV that can prevent damage or fire to the camera or built-in parts by continuing the operation while maintaining the low voltage mode when connecting a camera that does not support PoC in an environment composed of PoC. It is to provide a power and control signal superimposed transmission system using a video signal line.

In order to achieve the above object, a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention,

Equipped with a PoC camera module, it separates the power signal from the power overlap signal transmitted from the PoC receiver, generates power for driving the camera from the separated power signal, and transmits the video signal according to the drive of the camera module to the PoC receiver. And a PoC transmitter for outputting a clock signal to the PoC receiver to enable the PoC receiver to detect the PoC transmitter; And

A signal for processing the externally supplied power, applying power on the video signal line, superimposing transmission to the PoC transmitter, receiving and processing the video signal transmitted from the PoC transmitter, and controlling the camera module of the PoC transmitter A PoC receiving unit for transmitting to the PoC transmitting unit,

When the PoC receiver applies power to the video signal line and superimposes transmission to the PoC transmitter, first, a primary voltage as a relatively low voltage is applied to operate only the circuit detecting the PoC transmitter. It is characterized in that it transmits a secondary voltage as a high voltage relatively high compared to the primary voltage as a voltage supplied after detecting the clock signal from the PoC transmitter for a predetermined time.

Here, the PoC transmitter comprises: a TR superimposing circuit unit for separating the power signal from the power superimposed signal by minimizing distortion or damage to the image signal; A DC-DC conversion circuit for generating power (eg, +12VDC) for driving the camera from the separated power signal; An oscillation circuit unit for outputting a clock signal to the PoC receiving unit to enable the PoC receiving unit to detect the PoC transmitting unit; And a selection circuit unit for outputting an enable signal for allowing the oscillation circuit unit to output a clock signal to the oscillator circuit unit.

In addition, the PoC receiving unit includes a power output unit that superimposes power on the video signal line and transmits it to the PoC transmitting unit; A video signal processing unit for processing the video signal received from the PoC transmission unit and transmitting it to a recording device (DVR); A video detector for detecting a state of a video signal on the video signal line; The power output unit, the video signal processing unit, and the video detection unit as a whole manage and control, receive a transmission signal from the PoC transmission unit to determine the type of signal, and a control unit for performing a corresponding control operation according to the type of signal. It can be configured.

In addition, the PoC receiver may include a low voltage output unit that outputs a relatively low voltage according to the control operation of the control unit; A high voltage output unit for outputting a relatively high voltage compared to the voltage output from the low voltage output unit may be further included.

In this case, the relatively low voltage may be a voltage of DC 6 to 7V, and the relatively high voltage may be a voltage of DC 36 to 48V.

In addition, when the video detector determines a signal input from the PoC transmitter to the PoC receiver by the control unit, the signal portion that may have actual image data that may confuse the determination is determined based on a preset voltage level. It may be configured to cut and filter a high-frequency signal using a low pass filter (LPF), and then transmit the signal to the control unit.

In addition, the type of the signal determined by the control unit by receiving the transmission signal from the PoC transmission unit may include a PoC transmission unit connection status signal, a camera direct connection status signal, a signal no input or an abnormal status signal.

At this time, if the type of the signal determined by receiving the transmission signal from the PoC transmitter is a PoC transmitter connection state signal, the controller sets the power superimposition mode from a low voltage mode to a high voltage mode. By switching, it may be configured to supply a high voltage to the PoC transmitter.

In addition, if the type of signal determined by receiving the transmission signal from the PoC transmitter and determined by the control unit is a camera direct connection state signal, the control unit maintains the operation while maintaining a low voltage mode that does not damage the camera device. Can be configured.

In addition, when the type of signal determined by the control unit receiving the transmission signal from the PoC transmission unit is no signal input or an abnormal state signal, the control unit repeatedly performs a routine for detecting the input signal while maintaining the low voltage mode. Can be configured to

In addition, in the high voltage mode in which the PoC transmitter is supplying power for the camera, the control unit continuously monitors the input signal to determine whether the video signal is continuing, and the video loss state in which the video signal disappears is determined. If so, it may be configured to switch to a low voltage mode and return to a routine for detecting an input signal to perform an operation.

In addition, when the PoC receiver determines that the PoC transmitter is directly connected to a camera other than a PoC-supported camera, the PoC receiver continues to operate while maintaining the low voltage mode to prevent damage to the camera due to overvoltage on the video signal line. In the state, it may be configured to monitor whether the video signal input to the control unit continues.

In this case, if it is determined that the video signal is lost while monitoring whether the video signal continues or not, the control unit may be configured to return to a routine for detecting an input signal to perform an operation.

In addition, when the PoC receiver uses UTC (Up The Coax) communication, the video signal input from the PoC transmitter uses a path directly transmitted to the recording device (DVR) through only a passive element, and the UTC communication is not used. In some cases, it may be configured to use a path through which the input video signal passes through an amplifier or a buffer and is transmitted to the recording device (DVR).

According to the present invention, by superimposing and transmitting power and control signals using only a video signal line without installing a separate power line or control signal line, it is possible to reduce the difficulties and costs associated with CCTV installation and camera setup. There is an advantage.

1 is a diagram schematically showing the overall configuration of a CCTV system to which a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention is applied.
2 is a diagram schematically showing the configuration of a PoC transmitter of a power and control signal superimposed transmission system using a video signal line in a CCTV according to an embodiment of the present invention.
3 is a diagram schematically showing the configuration of a PoC receiver of a power and control signal superimposed transmission system using a video signal line in a CCTV according to an embodiment of the present invention.
4 is a diagram schematically showing a mechanism for generating a signal for detecting a PoC camera in an oscillation circuit unit.
5 is a diagram showing a high voltage operation mode of a PoC receiver in a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention.
6 is a view showing a low voltage operation mode of a PoC receiver in a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention.
7 is a view showing a low voltage operation mode of a PoC receiver when a camera that does not support PoC is connected in a system for transmitting power and control signals using a video signal line in a CCTV according to the present invention.
8 is a diagram showing a UTC path and an amplifier path as a video signal flow path of a PoC receiver side.

Terms or words used in this specification and claims are limited to their usual or dictionary meanings and should not be interpreted, and that the inventor can appropriately define the concept of terms in order to describe his own invention in the best way. Based on the principle, it should be interpreted as a meaning and concept consistent with the technical idea of the present invention.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. In addition, terms such as "...unit", "...group", "module", and "device" described in the specification mean units that process at least one function or operation, which is a combination of hardware or software or hardware and software. It can be implemented as

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram schematically showing the overall configuration of a CCTV system to which a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention is applied.

Referring to FIG. 1, the CCTV system 100 may include a PoC transmitter 110, a PoC receiver 120, and a DVR (image storage device) 130. As shown in Fig. 1, a video signal, a control signal, and power are transmitted and received between the PoC transmitter 110 and the PoC receiver 120 through one channel (video signal line), and the PoC receiver 120 and the DVR (video A video signal and a control signal are transmitted and received between the storage device 130 through one channel (video signal line). Here, the PoC transmission unit 110 and the PoC receiving unit 120 will be described in detail later.

The present invention makes physical (hardware) installation and software setup of CCTV cameras easy, thereby reducing the physical and time costs that are administered to CCTV installation and setup, and increasing the convenience of use. Power superimposed transmission technology using and control signal superimposed transmission technology using UTC (Up The Coax) are introduced. In other words, without installing a separate power line or control signal line, power is transmitted using only the video signal line (PoC) and control signal is transmitted (UTC), thereby reducing the difficulty and cost of work at the CCTV installation site. I want to solve it.

Then, hereinafter, the present invention as described above will be described in detail.

2 is a diagram schematically showing the configuration of a PoC transmission unit of a power and control signal superimposition transmission system using a video signal line in a CCTV according to an embodiment of the present invention, and FIG. 3 is a CCTV according to an embodiment of the present invention. It is a diagram schematically showing the configuration of a PoC receiver of a power and control signal superimposed transmission system using a video signal line.

2 and 3, a power and control signal superimposed transmission system using a video signal line in a CCTV according to the present invention may be configured to include a PoC transmitter 110 and a PoC receiver 120.

The PoC transmitter 110 has a PoC camera module 115, separates the power signal from the power overlap signal transmitted from the PoC receiver 120, generates power for driving the camera from the separated power signal, and The video signal according to the driving of the module 115 is transmitted to the PoC receiver 120, and a clock signal that enables the PoC receiver 120 to detect the PoC transmitter 110 is output to the PoC receiver 120 do.

The PoC receiving unit 120 processes power supplied from the outside (for example, AC 110 to 220V), applies power to the video signal line, superimposes the transmission to the PoC transmitting unit 110, and transmits it from the PoC transmitting unit 110. The transmitted video signal is received and processed, and a signal for controlling the camera module 115 of the PoC transmitter 110 is transmitted to the PoC transmitter 110.

The PoC receiving unit 120 in the superimposed transmission system of power and control signals using a video signal line in a CCTV according to the present invention having the above configuration is superimposed by the PoC transmitting unit 110 by applying power on the video signal line. In the transmission, first, a primary voltage as a relatively low voltage is transmitted as a voltage supplied to operate only the circuit that detects the PoC transmitter 110, and a clock signal from the PoC transmitter 110 is constant. As a voltage supplied after detection of a time (for example, for about 3 seconds), a secondary voltage as a high voltage relatively higher than the primary voltage is transmitted. In this case, the relatively low voltage may be a voltage of DC 6 to 7V, and the relatively high voltage may be a voltage of DC 36 to 48V.

The PoC transmission unit 110, as shown in Fig. 2, minimizes distortion or damage of the image signal to separate the power signal from the power overlapping signal TR superimposed circuit 111; A DC-DC conversion (eg, converting DC 48V or 36V to DC 12V) circuit unit 112 for generating power (eg, +12V DC) for driving the camera from the separated power signal; An oscillation circuit unit 114 for outputting a clock signal for allowing the PoC receiving unit 120 to detect the PoC transmitting unit 110 to the PoC receiving unit 120; And a selection circuit unit 113 for outputting an enable signal for allowing the oscillation circuit unit 114 to output a clock signal to the oscillator circuit unit 114. Here, the oscillation circuit unit 114 may be composed of an oscillator generating a clock of 4 MHz and an output switch IC circuit. Here, a description will be added of a mechanism for generating a signal for detecting a PoC camera in the oscillation circuit unit 114 as described above.

4 is a diagram schematically showing a mechanism for generating a signal for detecting a PoC camera in an oscillation circuit unit.

Referring to FIG. 4, the PoC transmitter 110 uses two voltages transmitted from the PoC receiver 120, which can apply a high voltage of DC 36V or 48V (hereinafter, HV) to a general camera that does not support PoC. This is to prevent burnout of the city camera. When the power is turned on, a low voltage of DC 6~7V (hereinafter referred to as LV) is received from the PoC receiver 120. A circuit that detects the "PoC transmitter" part (see Fig. 2) without operating the camera module and I/F circuit It is only the operating voltage.

LV is converted to a "HIGH" signal through the "RESISTOR DIVIDE and .TR circuit" (selection circuit part) 113 (see Fig. 2), and the 4 MHz clock among the sources of the oscillation circuit part 114 is the PoC receiver 120 It is used as an enable signal that is output to. This signal is sensed by the PoC receiver 120 for about 3 seconds to determine that there is a PoC transmitter, and then the PoC transmitter 110 receives the HV. In the HV mode, the selection circuit unit 113 selects an open output from the sources of the oscillator circuit unit 114, and waits in a state that does not affect the video signal. At the same time, the HV outputs the camera operation power (DC 12V) through the DC-DC conversion circuit unit 112, and accordingly, the camera module 115 operates so that the image signal is output to the PoC receiver 120. If the camera is a camera without a PoC transmitter, since the 4MHz clock cannot be sent to the PoC receiver 120, the PoC receiver 120 does not output HV, thus protecting the camera without a PoC transmitter (none PoC camera). You can do it.

That is, by adding only inexpensive and simple oscillation parts and selection circuits to the PoC transmission unit 110, interference to the video signal and control signal is minimized, and this signal is detected and determined by the PoC receiving unit (power transmission and video reception unit), The PoC receiver 120 can determine the correct operation mode and the voltage level according to the mode, and as a result, it is possible to prevent malfunctions and damages, which are likely to occur in the use and installation of PoC.

Referring back to FIG. 3, the PoC receiving unit 120 includes a power output unit 121 that superimposes power on the video signal line and transmits the superimposed power to the PoC transmitting unit 110; A video signal processing unit 122 for processing the video signal received from the PoC transmission unit 110 and transmitting the processed video signal to a recording device (DVR); A video detection unit 123 for detecting a state of a video signal on the video signal line; The power output unit 121, the image signal processing unit 122 and the video detection unit 123 are managed and controlled as a whole, and the type of signal is determined by receiving a transmission signal from the PoC transmission unit 110, and the type of signal It may be configured to include a control unit 124 that performs a corresponding control operation according to. Here, the control unit 124 may be composed of a programmable logic device (PLD), a field programmable gate array (FPGA), a central processing unit (CPU), and the like.

Here, the PoC receiving unit 120 as described above includes: a low voltage output unit 125 outputting a relatively low voltage according to the control operation performed by the control unit 124; A high voltage output unit 126 outputting a relatively high voltage compared to the voltage output from the low voltage output unit 125 may be further included.

In this case, the relatively low voltage may be a voltage of DC 6 to 7V, and the relatively high voltage may be a voltage of DC 36 to 48V.

In addition, when the video detection unit 123 determines the signal input to the PoC receiving unit 120 from the PoC transmission unit 110 by the control unit 124, there is a possibility that there is actual image data that may confuse the determination. It may be configured to cut out a signal portion based on a preset voltage level, filter a high-frequency signal using a low pass filter (LPF), and transmit the signal to the controller 124. Here, through this process, The signal input to the control unit 124 may be classified into a 4 MHz transmission unit determination signal, an image synchronization signal (eg, a signal having a frequency characteristic of 25 KHz to 35 KHz), and a non-change or random signal.

In addition, the type of the signal that the control unit 124 determines by receiving the transmission signal from the PoC transmission unit 110 may include a PoC transmission unit connection status signal, a camera direct connection status signal, a signal no input or an abnormal status signal. have.

At this time, when the type of the signal determined by receiving the transmission signal from the PoC transmission unit 110 by the control unit 124 is a PoC transmission unit connection state signal (ie, a 4 MHz transmission unit determination signal), as shown in FIG. Likewise, the control unit 124 converts the power superimposition mode from a low voltage mode to a high voltage mode, so that the transmitted power (high voltage) passes through the PoC transmitter of the PoC transmitter 110 to the camera power ( DC 12V) can be converted to be supplied.

In addition, when the type of signal determined by receiving the transmission signal from the PoC transmission unit 110 by the control unit 124 is a camera direct connection status signal (ie, an image synchronization signal from the camera), shown in FIG. As described above, the control unit 124 may be configured to maintain operation while maintaining a low voltage mode that does not damage the camera device.

In addition, when the type of signal determined by receiving the transmission signal from the PoC transmitter 110 by the control unit 124 is no signal input or an abnormal state signal (ie, no change or random signal), the above camera is directly connected. As in the case of a status signal (image synchronization signal from a camera), the controller 124 may be configured to repeatedly perform a routine for detecting an input signal while maintaining a low voltage mode.

In addition, the control unit 124 continuously monitors the input signal in the high voltage mode (see Fig. 5) in which the PoC transmitter 110 is supplying power for the camera to determine whether the video signal is continuing, and When a signal disappears into a video loss state, it may be configured to switch to a low voltage mode (see FIG. 6) and return to a routine for detecting an input signal to perform an operation.

On the other hand, when the PoC receiver 120 determines that the PoC transmitter 110 is directly connected to a non-PoC camera, not a camera supporting PoC (that is, a video signal is detected in a low voltage mode), the video signal line In order not to cause damage to the camera due to overvoltage on the image, as shown in FIG. 7, the operation is continued while maintaining the low voltage mode, and even in this state, the image signal input to the control unit 124 as in the high voltage mode. Can be configured to monitor the continuation of At this time, if it is determined that the video signal is lost while monitoring whether the video signal continues or not, the controller 124 may be configured to return to a routine for detecting an input signal to perform an operation.

In addition, the PoC receiving unit 120, as shown in Figure 8, when using the UTC (Up The Coax) communication, the video signal input from the PoC transmitting unit 110 is a direct recording device (DVR) through only a passive element When using the path transmitted to the side and not using the UTC communication (in general), the input video signal passes through an amplifier or buffer and is configured to use a path (red path) transmitted to the recording device (DVR). I can. Here, a little more explanation will be added regarding the use of such a path.

When an analog video signal is connected over a long distance, there is a problem in that an image is distorted or deteriorated due to characteristics on a line. In this case, a method of improving characteristics by connecting a signal amplifying circuit, a buffer, and a filter circuit to the image transmission unit is generally taken. However, due to the characteristics of the analog buffer or amplifier circuit configuration, in this case, only one-way signal transmission is possible from the camera side to the image receiver. In this case, the camera control signal (UTC signal), which must be transmitted in the opposite direction (video receiver → camera), cannot be transmitted, and the camera cannot be remotely controlled and manipulated by the video receiver. In other words, by selecting a method for improving the image signal, one important function (camera control signal transmission function) has to be discarded.

In the present invention, in order to solve this problem, the image flow path on the PoC receiver side is "a path through an amplifier or buffer" and "a path through which an input video signal is directly transmitted to the output side (recording apparatus (DVR)) through only a passive element" The system was divided into two types, and the method was introduced to be used selectively as needed.

That is, in case of using camera control (UTC communication), the "path through which the input video signal is directly transmitted to the output side through only the passive element" should be used, otherwise, the "path through the amplifier or buffer" should be used. This is the way.

In general, camera control (UTC communication) is temporarily used only during camera installation and maintenance. Except in this case, it is possible to use a "path through an amplifier or buffer", so that two requirements ( That is, a method capable of satisfying the video signal reception at the PoC receiving unit side and the camera control signal transmission toward the PoC transmitting unit) is taken.

At this time, the path selection method as described above is a manual method in which the controller 124 detects a user's physical switch operation and selects a path, and the controller 124 communicates with the image receiving device to automatically select a path if necessary. There may be an automatic method of switching.

As described above, the power and control signal superimposition transmission system using video signal lines in CCTV according to the present invention superimposes power and control signals using only video signal lines without installing separate power lines or control signal lines. By transmitting, there is an advantage of reducing the difficulty and cost associated with CCTV installation and camera setup.

In addition, when a camera that does not support PoC is connected in a PoC environment, there is an advantage of preventing damage to the camera or built-in components or fire by continuing the operation while maintaining the low voltage mode.

As described above, the present invention has been described in detail through preferred embodiments, but the present invention is not limited thereto, and various modifications and applications can be made within the scope of the technical spirit of the present invention. It is self-explanatory to the technician. Therefore, the true scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

110: PoC transmitting unit 111: TR superimposed circuit unit
112: DC-DC conversion circuit unit 113: selection circuit unit
114: oscillation circuit part 115: PoC camera module
120: PoC receiver 121: power output
123: video detection unit 124: control unit
125: low voltage output unit 126: high voltage output unit
130: DVR

Claims (14)

Equipped with a PoC camera module, it separates the power signal from the power overlap signal transmitted from the PoC receiver, generates power for driving the camera from the separated power signal, and transmits the video signal according to the drive of the camera module to the PoC receiver. And a PoC transmitter for outputting a clock signal to the PoC receiver to enable the PoC receiver to detect the PoC transmitter; And
A signal for processing the externally supplied power, applying power on the video signal line, superimposing transmission to the PoC transmitter, receiving and processing the video signal transmitted from the PoC transmitter, and controlling the camera module of the PoC transmitter A PoC receiving unit for transmitting to the PoC transmitting unit,
When the PoC receiver applies power to the video signal line and superimposes transmission to the PoC transmitter, first, a primary voltage as a relatively low voltage is applied to operate only the circuit detecting the PoC transmitter. And transmits a secondary voltage as a voltage relatively high compared to the primary voltage as a voltage supplied after detecting a clock signal from the PoC transmitter for a predetermined time,
The PoC receiver,
A power output unit that superimposes power on the video signal line and transmits it to the PoC transmission unit;
A video signal processing unit processing the video signal received from the PoC transmission unit and transmitting it to a recording device (DVR);
A video detector for detecting a state of a video signal on the video signal line;
The power output unit, the video signal processing unit, and the video detection unit as a whole manage and control, receive a transmission signal from the PoC transmission unit to determine the type of signal, and a control unit for performing a corresponding control operation according to the type of signal. and,
The type of the signal that the control unit determines by receiving the transmission signal from the PoC transmission unit includes a PoC transmission unit connection status signal, a camera direct connection status signal, a signal no input or an abnormal status signal,
When the type of signal determined by the control unit receiving the transmission signal from the PoC transmitting unit is a signal no input or an abnormal state signal, the control unit is configured to repeatedly perform a routine for detecting an input signal while maintaining a low voltage mode Power and control signal superimposed transmission system using a video signal line in CCTV, characterized in that.
The method of claim 1,
The PoC transmitter,
A TR superimposition circuit unit for separating the power signal from the power superimposed signal by minimizing distortion or damage to the image signal;
A DC-DC conversion circuit for generating power for driving the camera from the separated power signal;
An oscillation circuit unit for outputting a clock signal to the PoC receiving unit to enable the PoC receiving unit to detect the PoC transmitting unit; And
And a selection circuit unit for outputting an enable signal to the oscillator circuit unit to allow the oscillation circuit unit to output a clock signal. A power and control signal superimposition transmission system using a video signal line in a CCTV.
delete The method of claim 1,
The PoC receiver,
A low voltage output unit outputting a relatively low voltage according to the control operation of the control unit;
Power and control signal superimposed transmission system using a video signal line in CCTV, characterized in that it further comprises a high voltage output unit for outputting a relatively high voltage (High Voltage) compared to the voltage output from the low voltage output unit.
The method of claim 4,
Power and control using a video signal line in CCTV, characterized in that the relatively low voltage is a voltage of DC 6 to 7V, and the relatively high voltage is a voltage of DC 36 to 48V. Signal superimposed transmission system.
The method of claim 1,
When determining by the control unit the signal input from the PoC transmitter to the PoC receiver, the video detection unit cuts out a signal portion that may have actual image data that may confuse the determination based on a preset voltage level. , Power and control signal superimposition transmission system using a video signal line in CCTV, characterized in that configured to pass the signal to the control unit after filtering a high-frequency signal using a LPF (Low Pass Filter).
delete The method of claim 1,
When the type of the signal determined by the control unit receiving the transmission signal from the PoC transmission unit is a PoC transmission unit connection state signal, the control unit switches the power superimposition mode from a low voltage mode to a high voltage mode. Power and control signal superimposition transmission system using a video signal line in CCTV, characterized in that the high voltage is configured to be supplied to the PoC transmitter.
The method of claim 1,
When the type of the signal determined by the control unit receiving the transmission signal from the PoC transmitting unit is a camera direct connection state signal, the control unit is configured to maintain operation while maintaining a low voltage mode that does not damage the camera device. Power and control signal superimposed transmission system using video signal lines in CCTV, characterized in that.
delete The method of claim 1,
In the high voltage mode in which the PoC transmitter is supplying power for the camera, the control unit continuously monitors the input signal to determine whether the video signal is continuing, and when the video signal disappears, the video loss state is reached. Power and control signal superimposition transmission system using a video signal line in CCTV, characterized in that configured to switch to a low voltage mode and return to a routine for detecting an input signal to perform an operation.
The method of claim 1,
When the PoC receiver determines that the PoC transmitter is directly connected to a camera other than a PoC-supported camera, the PoC receiver continues to operate while maintaining the low voltage mode to prevent damage to the camera due to overvoltage on the video signal line. Power and control signal superimposition transmission system using a video signal line in CCTV, characterized in that configured to monitor whether the video signal input to the control unit continues.
The method of claim 12,
When it is determined that the video signal is lost while monitoring the continuation of the video signal, the control unit is configured to return to a routine for detecting the input signal and perform an operation. Transmission system.
The method of claim 1,
When the PoC receiver uses the UTC (Up The Coax) communication, the video signal input from the PoC transmitter uses a path through which the video signal is directly transmitted to the recording device (DVR) through only a passive element, and the UTC communication is not used. Is a power and control signal superimposed transmission system using a video signal line in CCTV, characterized in that configured to use a path through which the input video signal passes through an amplifier or a buffer and is transmitted to a recording device (DVR).

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