As an ordinary data transmission, there are many kinds of its kind; in the field of video surveillance, image and video data is particularly important, of course, its transmission is not the same. Especially when digital surveillance and analog surveillance cannot control the security market, multiple transmission media such as coaxial cables, twisted pairs, and optical fibers are also faced with a melee. Some people say that coaxial cable is still the mainstream wire for monitoring the market; it is said that optical fiber is the king of HD transmission. No matter what kind of transmission method or transmission cable is used, we should adopt different transmission methods and media in the face of different demands. Optical fiber market to force copper prices rise hardly fall First of all, let's look at the market development trend of the two. On February 8, Unicom announced that ADSL and optical fiber users can enjoy free high-speed bandwidths of 10M and 20M. Increasing the network bandwidth under the same package tariffs is also a blessing for disguised price cuts. Although the cost of optical fiber is high, when the network environment matures, optical fiber transmission can not only reduce the cost of the monitoring system, but also guarantee the transmission effect. When the optical fiber market frequently broadcasts good news, what about the coaxial cable market? According to the latest news on the 8th, copper prices continued to fluctuate at a high level, at a price of 3.9 U.S. dollars per pound. It seems that in terms of cost, the prospects for the copper market are worrying. For the monitoring transmission problem, the author also interviewed an engineering business friend. He said that at present, the transmission market is dominated by fiber optics. Since the copper line cost is too high, it is already in a semi- phase-out phase. However, according to the different needs of users and the different characteristics of layout monitoring, coaxial cable is still in use, but the project cost will be slightly increased. Is it true that the coaxial cable will not be able to recover from it? The answer is of course negative. When coaxial cables face a market crisis, products represented by HD-SDI and coaxial cable security links are born. Although HD-SDI can solve the problem of the quality of coaxial cable transmission, HD-SDI products must also be high-quality products and the product cost is high. In short, when the network environment gradually matures, the optical transmission market has a bright future. The coaxial cable is slightly obstructed due to cost issues. In fact, whether it is optical fiber or coaxial cable, there will be attenuation in the image transmission process. The above data shows that different degrees of attenuation occur depending on the bandwidth and transmission distance when transmitting different images. Especially in the past two years, copper wire clad aluminum and other products have emerged in the transmission market in the case of a significant increase in copper wire prices. The copper line is responsible for transmission, while the external aluminum line is responsible for shielding interference. In the era of high-definition digital signals, the combination of HD-SDI technology and coaxial cables solved some of the interference problems, and achieved frequency compensation and other functions, extending the transmission distance to 100m. The characteristic of optical fiber transmission lies in its dependence on optical signals, which has the advantage that it can not be ignored in long-distance transmission; secondly, the optical fiber band is 1.25G and 2.5G, and the bandwidth of 1080p image signal at 30 frames/s is 1920×1080×16×. 30=995.328M is approximately 1G, which is less than the rated frequency band of the optical fiber and can fully meet the demand for high-definition monitoring. In fact, careful people will find that the frequency of the HD-SDI interface is up to 1.48G, and the theoretical data is also fully capable of high-definition image requirements, but this requires internal transfer, which has a lot of limitations in high-speed ball and infrared cameras. Therefore, the high-definition transmission of HD-SDI and coaxial cables also encountered bottlenecks. When the coaxial cable encounters a bottleneck, twisted-pair transmission appears to be a popular product in the surveillance market when fiber transmission encounters short distances and high costs. Although it has the same drawbacks as the coaxial cable in the SD transmission, it can realize the shunt transmission due to its "two-wire combination" method, which cancels out the influence of high-frequency attenuation; in addition to its inherent anti-interference ability, Unique gimmick in network signal transmission. The story of "Observing Fisherman's Benefits" has been heard. When the coaxial cable and optical fiber are inseparable, will the appearance of twisted pair lead to the attention of "ancient people" and "come in?" When the two generations of products can not be completely replaced and replaced, the emergence of new generation products may solve the urgent need. The author believes that twisted-pair cable is a transitional product of current monitoring transmission, and its transmission medium has not changed, and a new breakthrough has been achieved in transmission mode. According to the author's investigation, the "hybrid" transmission method is more common in current monitoring systems. In the mature network environment, optical fiber communication is set up to achieve wide-range high-bandwidth communication; in the short range, the baseband transmission of the coaxial cable is realized and the cost is reduced; in addition, users with more requirements can also use the computer network protocol. Through the image compression process, the network cable is used for transmission. Monitoring transmission When the optical fiber encounters coaxial cable, we cannot distinguish who wins or loses. We only clarify the application fields and their respective characteristics. When HD-SDI becomes popular in the future, when optical fiber transmission solves short-distance transmission, when the cost of copper is reduced... When all technologies are superior, perhaps the monitoring transmission has been wirelessized. Monitoring the future is even more exciting because of the transmission. Custom Megaphone,High Power Wireless Megaphone,Wireless Portable Megaphone,Portable Magnetic Megaphone SHAOXING SUNSHINE ELECTRONIC CO.,LTD , https://www.crownlamp.com
HD monitoring transmission media determines transmission quality
When high-definition surveillance becomes more and more popular, in addition to high-definition surveillance cameras, high-definition transmission has become a key factor in determining picture quality. The quality of the output varies with different transmission media. First of all, let's look at the effect of SD to HD transmission: SD transmission uses analog signals, and the bandwidth is 6M. Using a 75-5 coaxial cable can transmit 100m without loss of picture quality. In the HD era, a 1080p image requires a bandwidth of 27M. Its bandwidth is 3.5 times that of standard definition, so theoretically the transmission distance is less than 30m. When high-definition surveillance comes, do you think that the coaxial cable can continue to shoulder heavy responsibilities? 
Release date:2012/2/10 11:39:56