Numerous progress has been made in fiber optic communication technologies to keep pace with the accelerating demand for reliable optical performance. Passive optical network (PON) serves as an innovative and practical technologies that put fiber to the home into reality. Simply by using PON fiber splitters which contain no electronics nor power supplies, a single PON network interface can be shared among many subscribers. Then, how could fiber splitter achieve this? We will explain it in this article.
Fiber splitter, also named beam splitter, takes a single fiber optic signal and divides it into multiple signals. It is used to split one beam of optical fiber light into several parts at a certain ratio. For instance, when a beam of optical light transmitted from a 1X4 equal ratio splitter, it will be divided into 4 optical light, that each beam is 1/4 or 25% of the original source one. Fiber splitters are integral components and widely used in most PON. The diagram below shows how light in a single input fiber can split between four individual fibers (1×4).
Splitters can be built using various single-mode and multimode optical fibers, and with most connector types for various applications, among which FC and SC connectors are typically the most common ones. Fiber splitters are the network elements that put the passive in PON and are available in a variety of split ratios, including 1:8, 1:16, and 1:32.
The widely used type of fiber splitter splits the output evenly, with half the signal going to one leg of the output and half going to the other. However, it is still possible to get splitters that use a different split ratio, putting a larger amount of the signal to one side than the other. Splitters are identified with a number that represents the signal division, such as 50/50 if the split is even, or 80/20 if 80% of the signal goes to one side and only 20% to the other.
Some kind of fiber splitters are actually able to work in either direction. Which means that if the device is installed in one way, it acts as a splitter that divides the incoming signal into two parts, sending out two separate outputs. While it is installed in reverse, it acts as a coupler that takes two incoming signals and combines them into a single output. Whether a splitter is combining light in the upstream direction or dividing light in the downstream direction, it still introduces the same attenuation to an optical input signal (a little more than 3 dB for each 1:2 split).
An optical splitter is an essential component used in a FTTH PON where a single optical input is split into multiple output. This enables the deployment a point to multi point (P2MP) physical fiber network with a single OLT port serving multiple ONTs. The most common splitters deployed in a PON system is a uniform power splitter with a 1: N or 2: N splitting ratio, where N is the number of output ports.
The optical splitter in a PON system functions to share the cost and bandwidth of the OLT among multiple ONTs as well as reduce the fiber lines required in the OSP. Splitters can be deployed in a centralized splitting configuration or a cascaded splitting configuration depending on the customer distribution. The 1: N splitters are usually deployed in networks with a star configuration while 2: N splitters are usually deployed in networks with a ring configuration to provide physical network redundancy
Fiber splitter also can be used in the GPON network. Note that the splitter can be deployed in the Central Office (CO) alongside the OLT, or it may be deployed in an outside plant (OSP) cabinet closer to the subscribers. What is more, the fiber splitter can be deployed in the basement of a building for a multiple dwelling unit (MDU) installation.
Fiber splitter provides a reliable and feasible solution for PON system. Serving as a vital passive optical component, it enables a single network interface to be shared by multiple users. Which is proved to be cost-effective, and will do you a good return in the long run.