CN-121985100-A - Device for transmitting CCTV signals by using optical fibers in long distance

CN121985100ACN 121985100 ACN121985100 ACN 121985100ACN-121985100-A

Abstract

The invention discloses a device for transmitting CCTV signals by using optical fibers in long distance, which relates to the technical field of outdoor long-distance signal transmission and comprises a front end acquisition end, an optical fiber transmission section, a rear end receiving end and an auxiliary protection structure, wherein a signal connection port of the front end acquisition end is fixedly connected with one end of the optical fiber transmission section in a plugging manner, the other end of the optical fiber transmission section is fixedly connected with a connection port of the rear end receiving end in a plugging manner, and the front end acquisition end and the rear end receiving end are both provided with the auxiliary protection structure. The device for transmitting CCTV signals by using the optical fibers in a long distance is free from loss by the arranged optical fiber transmission section, supports no relay transmission in 20 km, has no blurring and no smear in image quality, and is far beyond a coaxial cable (part only supports transmission in hundred meters), and the arrangement of an auxiliary protection structure ensures that the device has strong anti-interference capability, wherein the optical fibers do not conduct electromagnetic signals, can resist industrial interference and lightning interference, and is suitable for strong interference scenes such as ships, substations, oil fields, railways and the like.

Inventors

QIN YONGHUI
AN XIAOLI
CHEN JIA
SHEN HAIMING
ZHANG JITAO

Assignees

江苏扬子三井造船有限公司

Dates

Publication Date: 20260505
Application Date: 20260206

Claims (9)

1. The device for transmitting CCTV signals by utilizing optical fibers in a long distance is characterized in that the CCTV signal transmission device comprises a front end acquisition end, an optical fiber transmission section, a rear end receiving end and an auxiliary protection structure, a signal connection port of the front end acquisition end is fixedly connected with one end of the optical fiber transmission section in a plugging manner, the other end of the optical fiber transmission section is fixedly connected with a connection port of the rear end receiving end in a plugging manner, the front end acquisition end and the rear end receiving end are provided with the auxiliary protection structure, the optical fiber transmission section is composed of an armored single-mode optical fiber, and the outer protection of the optical fiber transmission section is enhanced and protected by an armor layer and an anticorrosive layer.
2. The apparatus for long distance CCTV signal transmission using optical fiber according to claim 1, wherein the front-end acquisition terminal comprises: The high-definition CCTV camera supports switching acquisition of 1080P and 4K resolution, the pixel density is more than or equal to 200 ten thousand pixels/inch, a 3A algorithm is adopted, the signal to noise ratio can be optimized to be more than or equal to 50dB in a low-light environment at night, the picture noise and smear are restrained, the audio acquisition unit integrates an omnidirectional electret microphone, the pickup range is 5-10 meters, the frequency response range is 20Hz-20kHz, the echo cancellation function is supported, the synchronous transmission delay of audio and video is ensured to be less than or equal to 50ms, meanwhile, the module shell is made of an aluminum alloy material, the IP67 waterproof and dustproof grade is matched with outdoor installation scenes; the electro-optical conversion unit is arranged in the high-definition CCTV camera, adopts an integrated laser emission component, is compatible with an analog CVBS signal and a digital HDMI signal which are output by the front end, converts an electric signal into an optical signal in a direct modulation mode, selects a special DFB laser for a single-mode fiber with the wavelength of 1310nm or 1550nm, outputs the optical power in the range of-5-0 dBm, has the extinction ratio of more than or equal to 10dB, ensures the stability of the signal transmitted in a long distance, ensures the conversion efficiency of the module of more than or equal to 98 percent, has the response speed of less than or equal to 1ns, is internally provided with a temperature compensation circuit, can automatically calibrate the laser power, avoids the signal attenuation caused by environmental temperature change, has the module size of 120mm multiplied by 80mm multiplied by 30mm, and supports DIN guide rail installation.
3. The device for long-distance transmission of CCTV signals by using optical fibers according to claim 2, wherein a professional noise reduction chip is additionally installed inside the high-definition CCTV camera, and the professional noise reduction chip is used for automatically performing noise reduction and impurity removal on the collected audio information data so as to remove interference data in the audio data.
4. The device for transmitting CCTV signals over long distances by using optical fibers according to claim 3, wherein the armored single-mode optical fibers are industrial single-mode optical fibers as core transmission carriers, the diameter of the fiber cores is precisely controlled to be 9 μm, the device has the technical advantages of low dispersion and low transmission loss, the transmission loss is less than or equal to 0.3dB/km, the maximum 20 km relay-free direct transmission is supported, no signal relay equipment is required to be additionally arranged, the deployment cost and maintenance difficulty of the system are reduced, the outer layers of the optical fibers are designed by adopting multi-layer armored protection layers, the characteristics of stretching resistance, corrosion resistance and mechanical impact resistance are achieved, the device can be directly applied to complex laying scenes such as outdoor buried and overhead, and the device is suitable for various severe natural environments.
5. The device for transmitting CCTV signals over long distances by using optical fibers according to claim 4, wherein the back-end receiving and displaying module comprises a back-end processing and displaying module, which is mainly composed of an integrated high-definition video decoder, a high-capacity hard disk video recorder and a professional high-definition display, wherein the decoder supports multi-format audio and video decoding, can rapidly analyze coded signals transmitted by the front-end, realizes real-time display of monitoring pictures, has no clamping and smearing, and the hard disk video recorder supports high-capacity storage and cyclic video recording, can store monitoring history data for a long time, has rapid retrieval and history return visit functions, supports accurate video acquisition according to time and point positions, reserves a network interface at the same time, can seamlessly access a local area network and a wide area network, realizes remote access, viewing and operation of the monitoring pictures, and meets the different-place monitoring requirements.
6. The device for transmitting CCTV signals over long distances by using optical fibers according to claim 5, wherein the rear receiving end further comprises a photoelectric conversion unit which is deployed at the monitoring rear end and is responsible for receiving optical signals transmitted by the optical fibers and finishing reverse conversion, the optical signals are accurately restored to digital electric signals through the high-sensitivity photoelectric detector and are completely matched with the front end output signal system, the high-performance signal amplifying chip is built in the module, so that tiny signal loss in the optical fiber transmission process can be intelligently compensated, the problems of signal attenuation and distortion after long-distance transmission can be effectively avoided, the consistency of the output electric signals and the front end acquisition signals can be ensured, and the on-site real audio/video information can be restored.
7. The device for long-distance transmission of CCTV signals using optical fibers according to claim 6, wherein a signal amplifying chip is additionally installed in the back-end processing display module, and is used for automatically performing intelligent compensation and optimization to eliminate signal attenuation and distortion, so as to ensure that the restored electrical signals are completely consistent with the original signals collected by the front-end, and provide a high-quality signal source for subsequent processing and display.
8. The device for transmitting CCTV signals over long distances by using optical fibers according to claim 7, wherein the auxiliary protection module is used for providing all-weather protection for the whole device, and the front-end signal acquisition module, the rear-end processing display module and each conversion unit are respectively provided with professional lightning protection and antistatic protection circuits.
9. The device for transmitting CCTV signals over long distances by using optical fibers according to claim 8, wherein the interfaces of the front end acquisition end and the rear end receiving end are SC/FC waterproof connectors, the device has IP67 level waterproof and dustproof characteristics, can adapt to outdoor humid and dusty environments, and meanwhile, the whole device has a wide temperature working design, can cover-40 ℃ to 85 ℃ in a working temperature range, can stably operate in extreme climatic environments such as high and cold conditions and high temperature conditions, and can realize all-weather monitoring without rest all the year round.

Description

Device for transmitting CCTV signals by using optical fibers in long distance Technical Field The invention relates to the technical field of outdoor long-distance signal transmission, in particular to a device for transmitting CCTV signals by using optical fibers in a long distance. Background The core of outdoor long-distance signal transmission is to select an adaptation scheme according to signal types (wired or wireless, analog or digital), transmission distance, bandwidth requirements and environmental conditions, the core solves three problems of signal attenuation, interference and link stability, the main stream scheme is divided into two main types of wireless transmission and wired transmission, the wireless is flexibly deployed to be the first choice outdoors, the wired is suitable for scenes with extremely high requirements on stability and bandwidth, and the long-distance signal transmission work is mostly selected by using wires in order to improve the stability of CCTV signal transmission; However, when the CCTV signal is transmitted remotely, the signal is easily attenuated, the image quality is blurred, and the pain point is easily affected by electromagnetic interference after the influence of surrounding power cables and other factors. Disclosure of Invention The present invention is directed to an apparatus for long-distance transmission of CCTV signals using optical fibers, so as to solve the above-mentioned problems in the related art. The CCTV signal transmission device comprises a front end acquisition end, an optical fiber transmission section, a rear end receiving end and an auxiliary protection structure, wherein a signal connection port of the front end acquisition end is fixedly connected with one end of the optical fiber transmission section in a plugging manner, the other end of the optical fiber transmission section is fixedly connected with a connection port of the rear end receiving end in a plugging manner, the front end acquisition end and the rear end receiving end are both provided with the auxiliary protection structure, the optical fiber transmission section is composed of an armored single-mode optical fiber, and the external protection of the optical fiber transmission section is enhanced and protected by an armor layer and an anti-corrosion layer. Further, the front-end acquisition end includes: The high-definition CCTV camera supports switching acquisition of 1080P (1920 multiplied by 1080,30 frames/second) and 4K (3840 multiplied by 2160,60 frames/second), the pixel density is more than or equal to 200 ten thousand pixels/inch, a 3A algorithm (automatic focusing, automatic exposure and automatic white balance) is adopted, the signal to noise ratio can be optimized to be more than or equal to 50dB under a night low-light environment (illuminance less than or equal to 0.01 lux), picture noise and smear are restrained, an audio acquisition unit is integrated with an omnidirectional electret microphone, the pickup range is 5-10 m, the frequency response range is 20Hz-20kHz, an echo cancellation function is supported, the synchronous transmission delay of audio and video is less than or equal to 50ms, meanwhile, a module shell is made of an aluminum alloy material, and an IP67 waterproof dustproof grade is suitable for outdoor installation scenes; The electro-optical conversion unit is arranged in the high-definition CCTV camera, adopts an integrated laser emission component, is compatible with an analog CVBS signal (1 Vpp,75 omega impedance) and a digital HDMI signal which are output by the front end, converts an electric signal into an optical signal through a direct modulation mode, selects a special DFB laser with the wavelength of 1310nm (transmission distance of less than or equal to 20 km) or 1550nm (transmission distance of less than or equal to 40km, and is optionally matched with a single-mode fiber, outputs optical power in the range of-5 to 0dBm, has an extinction ratio of more than or equal to 10dB, ensures the stability of long-distance transmission signals, has the module conversion efficiency of more than or equal to 98 percent, has the response speed of less than or equal to 1ns, is internally provided with a temperature compensation circuit (working temperature of-40 ℃ to 85 ℃) and can automatically calibrate the laser power, avoids signal attenuation caused by environmental temperature change, has the module size of 120mm multiplied by 80mm multiplied by 30mm, and supports DIN guide rail installation. Furthermore, a professional noise reduction chip is additionally arranged in the high-definition CCTV camera and is used for automatically carrying out noise reduction and impurity removal processing on the collected audio information data so as to remove interference data in the audio data. Furthermore, the armored single-mode fiber adopts an industrial single-mode fiber as a core transmission carrier, the diameter of the fiber core is accurately con