Many enterprises of storage area network (SAN) use short jumper cables, distribution frame, and covered in a computer center floor level 100 meters distance of the combination of fiber optic repeater, wall or ceiling insulation layer air pipe or seat at the top of the pipe.Enterprise center date may be connected to related fiber distribution frame 25000.In order to reduce costs and reduce the interference on the network, the cable is typical of repeated use as long as possible, spanning several generations of servers and storage devices;Very easy to move distribution frame and use a long jumper cable, rather than change the trunk cable installed.In fact, assuming that installed in the same as the old fiber, its purpose is to support FDDI and ESCON.This is a proof of fiber optic cable, is still used today, most of the infrastructure of high reliability.Therefore, it has become a significant and practical problems, to determine how long the installed multimode optical fiber infrastucture can continue to be recycled.
Demand a higher data rate, and combined with a reuse installed fiber desire, caused the OM3 optical fiber used in combined with traditional multimode cable growing interest.Most manufacturing dalai is not recommended in the same mixture of different types of multimode optical fiber link.This may at first saw not intuitive;If in 50 micron fiber to improve the bandwidth compared with 62.5 micron fiber, may be in addition to replace at least some of the installation of the benefits of the fiber will provide at least one partical.This is not the case;In fact, the mixing of different types of fiber may cause because when the optical fiber type of coupling one to another in the process of technical problems, to the instability of the link.This problem has been widely described in the technical literature, and does not support any recent industrial standard.When optical fiber type of coupling one to another, there are few;Larger fiber ACTS as a bucket to capture the entire optical signals.However, all of the data communication link is a two-way street, so since the childhood of the diameter of the fiber optic each transition.This causes two fiber corresponding transition from big to small diameter.This leads to two significant role.First, because people with the possible exception, some of the light signal is converted to a smaller core in the process of the fiber loss.Second, and more importantly, not all the large core optical fiber transmission mode will support in smaller core fiber.This leads to the effects of modal noise, which depends on the type of laser source, laser ring flux, modal distribution and spot size, and the bandwidth of the fiber and numerical aperture.Simulation and measurement for tens of thousands of links made to characterize the impulse response of the fiber;These calculations suggest that mixed mode, can cause the link failure in his life, in some cases high statistical probability.
If we limit their combined with different bandwidth of fiber into a single link, however, we can estimate, can by assuming a gaussian shaped the transfer function of optical fiber segments to achieve a good approximation of the effective distance.This simplified method should plan as a guide only, because it does not consider the statistical performance of specific fiber changes.For example, consider a previously installed 50 microns multimode fiber with low bandwidth, B1 - km (500 MHZ).The original cable is 75 meters long;It now needs to achieve a new device is 100 meters, so a new part of the cable connection.In an effort to achieve the best performance, the new cable used recently used fiber has higher bandwidth, B2 - km (2000 MHZ).We were asked to determine whether this combination can be support 10- GHz signal transmission.
Fiberstore is the largest Manufacturer Supplier of Fiber Cables in China. We can provide almost all the special fibers for optical communication systems including those introduced in this article and correspondingly we also have various kind of fiber optic patch cables in our store.
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