What is PLC Splitter?
The Planar Waveguide Circuit splitter (PLC Splitter) divides one or two beams of light evenly into multiple beams or combines multiple beams of light into one or two beams. Its high splitting ratio of 1×64 provides a low-cost, high-stability, and reliable light distribution solution.
It is suitable for connecting the central office and terminal equipment in passive optical networks (EPON, BPON, GPON, etc.) and FTTx networks and realizing the splitting of optical signals.
PLC Splitter is one of the most important passive optical components in a fiber optic link, with one or more inputs and multiple outputs. Its three most important components are the input end, output end, and chip of the fiber optic array. The design and assembly of these three components play an essential role in whether the PLC splitter can work stably and typically.
The chip is one of the key components of the PLC splitter. It offers 1xN (N=2, 4, 8, 16, 32, 64) and 2xN (N=2, 4, 8, 16, 32, 64) splitting ratios. The figure below is a typical design of a 1×8 PLC splitter chip.
- The loss is not sensitive to optical wavelength, which can meet the transmission needs of different wavelengths;
- Uniform light splitting, which can evenly distribute signals to users;
- Compact structure and small size, it can be directly installed in various existing transfer boxes without leaving a large installation space;
- Multiple shunt channels for a single device;
- Low cost, the more branches, the more obvious the cost advantage.
Depending on the network structure, the distribution of PLC splitters in the network is also different. Usually divided into two types: centralized distribution and cascade distribution.
Centralized Distribution of PLC Splitters
The centralized distribution of PLC optical splitters means that the splitters are centrally installed at a certain position between the optical line terminal (OLT) and the optical network unit (ONT). It is more suitable for network applications with more concentrated users.
The splitting ratio of the PLC splitter used here is usually 1:32 and 1:64. As shown in the figure below, a PLC splitter with a splitting ratio of 1:32 can be used to deliver network services at the central office to 32 home users:
PLC splitters used in fiber optic distribution hubs include tray type, plug-in Cassette type, and ABS box type; PLC optical splitters used in optical fiber terminal boxes include bare fiber type, etc.
Cascade Distribution of PLC Splitter
The biggest difference between them is that the cascade distribution has two levels of light splitting (the concentrated distribution has only one level of light splitting).
The following figure is an example diagram of delivering network services to 32 home users through the cascading distribution of PLC splitters. From the figure, we can see that each splitter is distributed, the light splitter ratio is 1:4, and the splitting ratio of the secondary beam splitter is 1:8.
This distribution method is more complex than centralized distribution, but it can maximize the use of fiber optic resources, and the wiring is flexible, which is more suitable for network applications where users are scattered. PLC splitters suitable for this application include bare fiber type, mini-tube type, ABS box type, etc.
How does the Fiber Optic Splitter Work?
Generally speaking, when a fiber optic signal is transmitted in a single mode, all the light energy can’t be concentrated in the fiber core. A small amount of energy will propagate through the fiber’s cladding. If the two fibers are close enough, light traveling in one fiber can enter the other. Therefore, the redistribution technology of light signals can be realized in multiple fiber optics, and the optical fiber splitter emerges as the times require.
Specifically, a passive beam splitter can split or separate an incident beam into several beams according to a certain ratio. The 1×4 split configuration described below is the basic structure: an incoming beam from a single input cable is split into four beams and transmitted through four separate output cables. For example, if the incoming fiber optic cable carries 1000 Mbps of bandwidth, each user at the end of the outgoing fiber optic cable can use the network at 250 Mbps of bandwidth.
PLC Splitter Application
According to different types, optical splitters are usually mainly used in:
Bare fiber type: The bare PLC splitter is directly led out by fiber optic (generally ribbon optical fiber), and there is no end at both end. It is mainly suitable for occasions where disassembly is infrequent, inside the pigtail box or in the test gauge.
Mini-Tube Type: Mini-tube PLC refers to a small splitter component packaged in a steel tube and uses a 0.9mm loose tube for fiber output. It is mainly suitable for tight installation spaces. It does not need to be welded or cold spliced, such as optical cable splicing boxes and fiber optic splitting boxes, and can also be installed in plug-in and rack-mounted optical splitter combination boxes.
ABS box type: This is packaged in an ABS plastic box, and the port is led out by a pigtail. It is mainly used in the rack and installed in the optical cable transfer box when the optical fiber branch enters the home.
Plug-in Cassette type: The plug-in Cassette PLC is packaged in an ABS plastic box, and the port is end-type. The user access point needs to be split in the FTTX system. Its primary function is to terminate the optical cable entering the community or building. It has the functions of fixing, stripping, welding, jumping, and splitting optical fiber. Form into the end user.
Tray type: It is packaged in ODF integrated splicing tray, which can be installed in the ODF distribution frame.
Rack type: The rack PLC is packaged in a metal box and can be installed in a 19-inch 1U cabinet.
With the rapid growth of FTTx worldwide, the need for larger split configurations in the network to serve many users is also increasing. The PLC splitter allows a single PON network interface to be used by multiple users, maximizes the user capacity of the fiber optic network, and provides the best solution for network builders.