Device for long-distance transmission of CCTV signal by using optical fiber

Abstract

The invention discloses a device for long-distance transmission of a CCTV signal by using an optical fiber, and relates to the technical field of outdoor long-distance signal transmission, the device comprises a front-end acquisition end, an optical fiber transmission section, a rear-end receiving end and an auxiliary protection structure, and a signal connection port of the front-end acquisition end is fixedly connected with one end of the optical fiber transmission section in an insertion manner; the other end of the optical fiber transmission section is fixedly connected with the connecting port of the rear-end receiving end in an inserted mode, and the front-end collecting end and the rear-end receiving end are each provided with an auxiliary protection structure. According to the device for long-distance transmission of the CCTV signal by using the optical fiber, the optical fiber transmission section is arranged, so that the device has no loss in a long distance, supports no-relay transmission within 20 kilometers, no fuzzy image quality and no smear, and is far beyond a coaxial cable (partially only supports transmission within 100 meters), and an auxiliary protection structure is arranged; the optical fiber does not conduct electromagnetic signals, can resist industrial interference and lightning interference, and is suitable for strong interference scenes such as ships, transformer substations, oil fields, railways and the like.

Description

Technical Field

[0001] This invention relates to the field of outdoor long-distance signal transmission technology, specifically to a device for long-distance transmission of CCTV signals using optical fiber. Background Technology

[0002] The core of long-distance outdoor signal transmission is to select an appropriate solution based on the signal type (wired or wireless, analog or digital), transmission distance, bandwidth requirements, and environmental conditions. The core solution is to address three major issues: signal attenuation, interference, and link stability. The mainstream solutions are divided into two categories: wireless transmission and wired transmission. Wireless transmission is the preferred choice for outdoor use due to its flexible deployment, while wired transmission is suitable for scenarios with extremely high requirements for stability and bandwidth. In order to improve the stability of CCTV signal transmission, wired transmission is often chosen for long-distance signal transmission. Existing wired CCTV signal transmission mostly uses coaxial cables, but when transmitting signals over long distances, they suffer from signal attenuation, blurred image quality, and susceptibility to electromagnetic interference due to the influence of surrounding power cables and other factors. Summary of the Invention

[0003] The purpose of this invention is to provide a device for long-distance transmission of CCTV signals using optical fiber, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a device for long-distance transmission of CCTV signals using optical fiber, the CCTV signal transmission device comprising a front-end acquisition end, an optical fiber transmission section, a back-end receiving end, and an auxiliary protection structure, wherein the signal connection port of the front-end acquisition end is fixedly connected to one end of the optical fiber transmission section, and the other end of the optical fiber transmission section is fixedly connected to the connection port of the back-end receiving end, and both the front-end acquisition end and the back-end receiving end are equipped with auxiliary protection structures, wherein the optical fiber transmission section is composed of armored single-mode optical fiber, and its outer protection is reinforced by an armor layer and an anti-corrosion layer.

[0005] Furthermore, the front-end acquisition terminal includes: High-definition CCTV camera: It supports switching between 1080P (1920×1080, 30 frames / second) and 4K (3840×2160, 60 frames / second) resolutions, with a pixel density of ≥2 million pixels / inch. It adopts the 3A algorithm (autofocus, auto exposure, auto white balance) and can optimize the signal-to-noise ratio to ≥50dB in low-light environments at night (illuminance ≤0.01lux), suppressing image noise and ghosting. The audio acquisition unit integrates an omnidirectional electret microphone with a pickup range of 5-10 meters and a frequency response range of 20Hz-20kHz. It supports echo cancellation to ensure audio and video synchronous transmission latency ≤50ms. At the same time, the module shell is made of aluminum alloy with an IP67 waterproof and dustproof rating, making it suitable for outdoor installation scenarios. Electro-optical conversion unit: Located inside the high-definition CCTV camera, it uses an integrated laser emitting component, compatible with both analog CVBS signals (1Vpp, 75Ω impedance) and digital HDMI signals output from the front end. It converts electrical signals into optical signals through direct modulation, using a single-mode fiber-optic dedicated DFB laser with a wavelength of 1310nm (transmission distance ≤20km) or 1550nm (transmission distance ≤40km, optional). The output optical power range is -5~0dBm, and the extinction ratio is ≥10dB, ensuring signal stability for long-distance transmission. The module conversion efficiency is ≥98%, the response speed is ≤1ns, and it has a built-in temperature compensation circuit (operating temperature -40°C~85°C) to automatically calibrate the laser power and avoid signal attenuation caused by changes in ambient temperature. The module size is 120mm×80mm×30mm, and it supports DIN rail mounting.

[0006] Furthermore, the high-definition CCTV camera is equipped with a professional noise reduction chip, which is used to automatically perform noise reduction and noise removal processing on the collected audio information data to remove interference data in the audio data.

[0007] Furthermore, the armored single-mode fiber uses industrial-grade single-mode fiber as the core transmission carrier, with a core diameter precisely controlled at 9μm. It has the technical advantages of low dispersion and low transmission loss, with a transmission loss of ≤0.3dB / km. It also supports direct transmission without repeaters for up to 20 kilometers, eliminating the need for additional signal repeater equipment, thus reducing system deployment costs and maintenance difficulty. The outer layer of the fiber adopts a multi-layer armored protective layer design, which has the characteristics of tensile strength, corrosion resistance, and mechanical shock resistance. It can be directly applied to complex laying scenarios such as outdoor underground and overhead installations, and is adaptable to various harsh natural environments.

[0008] Furthermore, the back-end receiving end includes: a back-end processing and display module: which is the core of the system for audio and video processing, storage, and display. It mainly consists of an integrated high-definition video decoder, a large-capacity hard disk recorder (NVR), and a professional high-definition display. The decoder supports multi-format audio and video decoding and can quickly parse the encoded signals transmitted from the front end to achieve real-time display of the monitoring screen without lag or ghosting. The hard disk recorder (NVR) supports large-capacity storage and loop recording, and can save historical monitoring data for a long time. It has fast retrieval and historical playback functions and supports precise retrieval of recordings by time and location. The module also reserves a network interface, which can seamlessly connect to the local area network and wide area network to realize remote access, viewing, and control of the monitoring screen and meet the needs of remote monitoring.

[0009] Furthermore, the back-end receiver also includes a photoelectric conversion unit: deployed at the monitoring back-end, responsible for receiving optical signals transmitted through optical fibers and completing reverse conversion, accurately restoring the optical signals into digital electrical signals through a high-sensitivity photoelectric detector, which is fully matched with the output signal format of the front end. The module has a built-in high-performance signal amplification chip, which can intelligently compensate for minor signal loss during optical fiber transmission, effectively avoid signal attenuation and distortion problems after long-distance transmission, ensure the consistency between the output electrical signal and the front-end acquired signal, and restore the real audio and video information on site.

[0010] Furthermore, the back-end processing and display module is equipped with a signal amplification chip, which is used to automatically perform intelligent compensation and optimization to eliminate signal attenuation and distortion problems, ensuring that the restored electrical signal is completely consistent with the original signal collected by the front end, and providing a high-quality signal source for subsequent processing and display.

[0011] Furthermore, the auxiliary protection module provides all-weather protection for the entire device. The front-end signal acquisition module, the back-end processing and display module, and each conversion unit are equipped with professional lightning and electrostatic protection circuits and surge protection technology, which can effectively resist sudden power interference such as lightning strikes and static electricity, and avoid equipment damage and signal interruption.

[0012] Furthermore, the interfaces of the front-end acquisition end and the back-end receiving end both adopt SC / FC waterproof connectors, which have IP67 waterproof and dustproof characteristics, and can adapt to outdoor humid and dusty environments. At the same time, the entire device has a wide temperature operation design, and the operating temperature range can cover -40°C to 85°C. It can operate stably in extreme climate environments such as high cold and high temperature, so as to achieve year-round, 24 / 7 monitoring.

[0013] This invention provides a device for long-distance transmission of CCTV signals using optical fiber, which has the following advantages: 1. This invention enables the device to operate at long distances without loss through the optical fiber transmission segment: it supports transmission without repeaters within 20 kilometers, with no blurring or ghosting in image quality, far exceeding that of coaxial cables (some of which only support transmission within 100 meters). At the same time, the auxiliary protective structure makes the device highly resistant to interference: optical fibers do not conduct electromagnetic signals and can resist industrial interference and lightning interference, making it suitable for strong interference scenarios such as ships, substations, oil fields, and railways.

[0014] 2. This invention features high-definition transmission capability: it is compatible with 4K high-definition signals to meet the requirements of modern life for capturing details, and supports parallel transmission of multi-channel signals (a single optical fiber can transmit 8 CCTV signals). It also has high stability: the optical fiber material is corrosion-resistant and anti-aging, with a service life of up to 20 years, low maintenance costs, and is suitable for long-term use in open areas on ships and outdoors. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall operation process of a device for long-distance transmission of CCTV signals using optical fiber according to the present invention. Figure 2 This is a schematic diagram of the front-end acquisition end structure of a device for long-distance transmission of CCTV signals using optical fiber according to the present invention. Figure 3 This is a schematic diagram of the optical fiber transmission section structure of a device for long-distance transmission of CCTV signals using optical fiber according to the present invention. Figure 4 This is a schematic diagram of the back-end receiver structure of a device for long-distance transmission of CCTV signals using optical fiber according to the present invention. Detailed Implementation

[0016] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0017] like Figures 1-2 As shown, a device for long-distance transmission of CCTV signals using optical fiber includes a front-end acquisition end, an optical fiber transmission section, a back-end receiving end, and an auxiliary protection structure. The signal connection port of the front-end acquisition end is fixedly connected to one end of the optical fiber transmission section. The front-end acquisition end includes: High-definition CCTV camera: It supports switching between 1080P (1920×1080, 30 frames / second) and 4K (3840×2160, 60 frames / second) resolutions, with a pixel density of ≥2 million pixels / inch. It adopts the 3A algorithm (autofocus, auto exposure, auto white balance) and can optimize the signal-to-noise ratio to ≥50dB in low-light environments at night (illuminance ≤0.01lux), suppressing image noise and ghosting. The audio acquisition unit integrates an omnidirectional electret microphone with a pickup range of 5-10 meters and a frequency response range of 20Hz-20kHz. It supports echo cancellation to ensure that the audio and video synchronous transmission delay is ≤50ms. At the same time, the module shell is made of aluminum alloy with an IP67 waterproof and dustproof rating, making it suitable for outdoor installation scenarios. The high-definition CCTV camera is equipped with a professional noise reduction chip to automatically process the acquired audio information data for noise reduction and noise removal to remove interference data in the audio data. Electro-optical conversion unit: Located inside the high-definition CCTV camera, it employs an integrated laser emitting component, compatible with both analog CVBS signals (1Vpp, 75Ω impedance) and digital HDMI signals output from the front end. It converts electrical signals into optical signals via direct modulation, using a single-mode fiber-optic dedicated DFB laser with a wavelength of 1310nm (transmission distance ≤20km) or 1550nm (transmission distance ≤40km, optional). The output optical power range is -5~0dBm, with an extinction ratio ≥10dB, ensuring signal stability over long distances. The module conversion efficiency is ≥98%, and the response speed is ≤1ns. It features a built-in temperature compensation circuit (operating temperature -40°C~85°C) to automatically calibrate the laser power, preventing signal attenuation due to ambient temperature changes. The module dimensions are 120mm×80mm×30mm, supporting DIN rail mounting. The other end of the fiber optic transmission section is fixedly connected to the back-end receiver via a plug-in interface. Furthermore, the front-end acquisition end... Both the receiving end and the back-end are equipped with auxiliary protection structures. The fiber optic transmission section consists of armored single-mode fiber, with its outer protection reinforced by an armor layer and an anti-corrosion layer. The armored single-mode fiber uses industrial-grade single-mode fiber as the core transmission carrier, with a core diameter precisely controlled at 9μm. It has the technical advantages of low dispersion and low transmission loss, with a transmission loss of ≤0.3dB / km. It also supports direct transmission without repeaters for up to 20 kilometers, eliminating the need for additional signal repeater equipment, reducing system deployment costs and maintenance difficulty. The outer layer of the fiber adopts a multi-layer armored protective layer design, which has tensile strength, corrosion resistance, and mechanical shock resistance. It can be directly applied to complex laying scenarios such as underground and overhead installations, and is adaptable to various harsh natural environments. At the same time, the armored single-mode fiber is equipped with a signal detection unit. When the fiber is interrupted or the optical power is abnormal (<-30dBm or >0dBm), the back-end module issues an audible and visual alarm and automatically switches to the backup fiber channel (dual fiber redundancy design) to ensure uninterrupted video transmission.

[0018] like Figures 1-2As shown, the system comprises a front-end acquisition unit, an optical fiber transmission section, a back-end receiving unit, and an auxiliary protection structure. The signal connection port of the front-end acquisition unit is fixedly connected to one end of the optical fiber transmission section, and the other end of the optical fiber transmission section is fixedly connected to the connection port of the back-end receiving unit. The back-end receiving unit includes a back-end processing and display module: this is the core of the system's audio and video processing, storage, and display. It mainly consists of an integrated high-definition video decoder, a large-capacity hard disk recorder (NVR), and a professional high-definition display. The decoder supports multi-format audio and video decoding and can quickly parse the encoded signals transmitted from the front end, achieving real-time display of the monitoring screen without lag or ghosting. The hard disk recorder (NVR)... (R) Supports large-capacity storage and loop recording, enabling long-term preservation of historical monitoring data. It features fast retrieval and historical playback functions, and supports precise retrieval of recordings by time and location. The module also reserves a network interface for seamless access to LANs and WANs, enabling remote access, viewing, and control of monitoring footage to meet remote monitoring needs. The backend receiver also includes a photoelectric conversion unit: deployed at the monitoring backend, responsible for receiving optical signals transmitted through fiber optics and performing reverse conversion. A high-sensitivity photodetector accurately restores the optical signal to a digital electrical signal, perfectly matching the front-end output signal format. The module incorporates a high-performance signal amplification chip to intelligently compensate for the optical transmission process. Minimal signal loss effectively avoids signal attenuation and distortion issues after long-distance transmission, ensuring consistency between the output electrical signal and the front-end acquired signal, and restoring the true audio and video information of the scene. The back-end processing and display module is equipped with a signal amplification chip, which automatically performs intelligent compensation and optimization to eliminate signal attenuation and distortion, ensuring that the restored electrical signal is completely consistent with the original signal acquired by the front end, providing a high-quality signal source for subsequent processing and display. Furthermore, both the front-end acquisition end and the back-end receiving end are equipped with auxiliary protection structures. The fiber optic transmission section is composed of armored single-mode fiber, and its outer protection is reinforced by an armor layer and an anti-corrosion layer. The auxiliary protection module uses… To provide all-weather protection for the entire device, the front-end signal acquisition module, the back-end processing and display module, and each conversion unit are equipped with professional lightning and electrostatic protection circuits and surge protection technology, which can effectively resist sudden power interference such as lightning strikes and static electricity, and avoid equipment damage and signal interruption. The interfaces of the front-end acquisition end and the back-end receiving end all use SC / FC waterproof connectors, which have IP67 waterproof and dustproof characteristics and can adapt to outdoor humid and dusty environments. At the same time, the entire device has a wide temperature operation design, and the operating temperature range can cover -40°C to 85°C. It can operate stably in extreme climatic environments such as high cold and high temperature, so as to achieve year-round, uninterrupted, all-weather monitoring.

[0019] In summary, combining Figures 1-2As shown, the working principle of the device for long-distance transmission of CCTV signals using optical fiber is as follows: First, the high-definition CCTV camera in the front-end acquisition end acquires the audio and video electrical signals of the scene in real time. Then, the professional noise reduction chip installed inside the high-definition CCTV camera performs noise reduction processing on the acquired audio and video signal data and transmits it to the electro-optical conversion unit. Then, the electro-optical conversion unit converts the electrical signal into an optical signal, and then the signal is transmitted over a long distance through the optical fiber transmission section. Secondly, when the electrical signal is transmitted to the back-end receiver through the optical fiber transmission section, the photoelectric conversion unit automatically receives the optical signal and restores it to an electrical signal. Then, the electrical signal is amplified and optimized by the signal amplification chip. Finally, the amplified and optimized electrical signal is processed by the decoder and displayed in real time on the monitor, while being stored in the hard disk recorder for real-time backup.

[0020] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A device for long-distance transmission of CCTV signals using optical fiber, characterized in that, The CCTV signal transmission device includes a front-end acquisition end, an optical fiber transmission section, a back-end receiving end, and an auxiliary protection structure. The signal connection port of the front-end acquisition end is fixedly connected to one end of the optical fiber transmission section, and the other end of the optical fiber transmission section is fixedly connected to the connection port of the back-end receiving end. Both the front-end acquisition end and the back-end receiving end are equipped with auxiliary protection structures. The optical fiber transmission section is composed of armored single-mode optical fiber, and its outer protection is reinforced by an armor layer and an anti-corrosion layer.

2. The device for long-distance transmission of CCTV signals using optical fiber according to claim 1, characterized in that, The front-end acquisition terminal includes: High-definition CCTV camera: It supports switching between 1080P and 4K resolution acquisition, with a pixel density of ≥2 million pixels / inch. It adopts the 3A algorithm, which can optimize the signal-to-noise ratio to ≥50dB in low-light environments at night, suppressing image noise and ghosting. The audio acquisition unit integrates an omnidirectional electret microphone with a pickup range of 5-10 meters and a frequency response range of 20Hz-20kHz. It supports echo cancellation to ensure that the audio and video synchronous transmission delay is ≤50ms. At the same time, the module shell is made of aluminum alloy, with an IP67 waterproof and dustproof rating, making it suitable for outdoor installation scenarios. Electro-optical conversion unit: Located inside the high-definition CCTV camera, it uses an integrated laser emitting component, compatible with both analog CVBS and digital HDMI signals output from the front end. It converts electrical signals into optical signals through direct modulation, using a dedicated DFB laser for single-mode fiber optics with a wavelength of 1310nm or 1550nm. The output optical power range is -5~0dBm, and the extinction ratio is ≥10dB, ensuring signal stability for long-distance transmission. The module conversion efficiency is ≥98%, and the response speed is ≤1ns. It has a built-in temperature compensation circuit that can automatically calibrate the laser power to avoid signal attenuation caused by changes in ambient temperature. The module size is 120mm×80mm×30mm, and it supports DIN rail mounting.

3. The device for long-distance transmission of CCTV signals using optical fiber according to claim 2, characterized in that, The high-definition CCTV camera is equipped with a professional noise reduction chip, which is used to automatically process the collected audio information data to remove noise and interference data from the audio data.

4. The device for long-distance transmission of CCTV signals using optical fiber according to claim 3, characterized in that, The armored single-mode fiber uses industrial-grade single-mode fiber as the core transmission carrier, with a core diameter precisely controlled at 9μm. It has the technical advantages of low dispersion and low transmission loss, with a transmission loss of ≤0.3dB / km. It also supports direct transmission without repeaters for up to 20 kilometers, eliminating the need for additional signal repeater equipment, thus reducing system deployment costs and maintenance difficulty. The outer layer of the fiber adopts a multi-layer armored protective layer design, which has the characteristics of tensile resistance, corrosion resistance, and mechanical shock resistance. It can be directly applied to complex laying scenarios such as outdoor underground and overhead installations, and is adaptable to various harsh natural environments.

5. The device for long-distance transmission of CCTV signals using optical fiber according to claim 4, characterized in that, The back-end receiving end includes: a back-end processing and display module: the core of the system for audio and video processing, storage, and display. It mainly consists of an integrated high-definition video decoder, a large-capacity hard disk recorder, and a professional high-definition display. The decoder supports multi-format audio and video decoding and can quickly parse the encoded signals transmitted from the front end to achieve real-time display of the monitoring screen without lag or ghosting. The hard disk recorder supports large-capacity storage and loop recording, and can save historical monitoring data for a long time. It has fast retrieval and historical playback functions and supports precise retrieval of recordings by time and location. The module also reserves a network interface, which can seamlessly connect to local area networks and wide area networks to realize remote access, viewing, and control of the monitoring screen, meeting the needs of remote monitoring.

6. The device for long-distance transmission of CCTV signals using optical fiber according to claim 5, characterized in that, The back-end receiver also includes a photoelectric conversion unit: deployed at the monitoring back-end, it is responsible for receiving optical signals transmitted by optical fiber and completing the reverse conversion. It accurately restores the optical signals into digital electrical signals through a high-sensitivity photoelectric detector, which is fully matched with the output signal format of the front end. The module has a built-in high-performance signal amplification chip, which can intelligently compensate for the slight signal loss during optical fiber transmission, effectively avoid signal attenuation and distortion problems after long-distance transmission, ensure the consistency between the output electrical signal and the front-end acquired signal, and restore the real audio and video information on site.

7. The device for long-distance transmission of CCTV signals using optical fiber according to claim 6, characterized in that, The back-end processing and display module is equipped with a signal amplification chip, which is used to automatically perform intelligent compensation and optimization to eliminate signal attenuation and distortion problems, ensuring that the restored electrical signal is completely consistent with the original signal collected by the front end, and providing a high-quality signal source for subsequent processing and display.

8. The device for long-distance transmission of CCTV signals using optical fiber according to claim 7, characterized in that, The auxiliary protection module is used to provide all-weather protection for the entire device. The front-end signal acquisition module, the back-end processing and display module, and each conversion unit are equipped with professional lightning and electrostatic protection circuits and surge protection technology, which can effectively resist sudden power interference such as lightning strikes and static electricity, and avoid equipment damage and signal interruption.

9. The device for long-distance transmission of CCTV signals using optical fiber according to claim 8, characterized in that, Both the front-end acquisition end and the back-end receiving end use SC / FC waterproof connectors at their interfaces, which have IP67 waterproof and dustproof characteristics, and can adapt to outdoor humid and dusty environments. At the same time, the entire device has a wide temperature operation design, with an operating temperature range covering -40°C to 85°C, and can operate stably in extreme climate environments such as high cold and high temperature, so as to achieve year-round, 24 / 7 monitoring.

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