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About:
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PLC (Planar Lightwave Circuit) splitter is an important component in PON (passive
optical network) where a single optical input is split into multiple outputs. This
makes it possible to deploy a Point to Multi Point physical fiber network with a
single OLT (optical line terminal) port serving multiple ONTs (optical network
terminal). The most common split ratios are 1:N or 2:N. N represents the output
ports, usually as 2, 4, 8, 16, etc. The optical input power is distributed uniformly
across all output ports. The <a href="https://www.ghcomms.com/plc-splitter/">PLC
Splitter</a> shares the cost and bandwidth of the OLT and reduces fiber lines. This
article will tell about how to keep a high quality PLC splitter from manufacturing to
testing sides.
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PLC splitter is composed by many miniature parts. Among them, there are three
main components: fiber array for the input and output, and the chip. These three main
components decide whether the PLC splitter is of good quality or not. Let’s see the
key manufacturing steps of a PLC splitter.
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Then how to determine the quality of a <a href="https://www.ghcomms.com/plc-
splitter/mini-plc-splitter/">Mini PLC Splitter</a>? The GR-1209 standards provides
comprehensive optical performance criteria. The following will introduce these
specifications such as optical bandpass, insertion loss, return loss, uniformity and
directivity.
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<strong>Optical Bandpass</strong>
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In a PON system, the downstream transmission uses 1490nm wavelength and 1310nm
wavelength for the upstream transmission. Besides, the requirement for RF video
overlay and network testing/maintenance should also be considered. The transmission
wavelength for RF video is 1550 nm. And the wavelengths for networking testing and
maintenance are 1550 nm and 1625 nm. So the standard opterating wavelength for a PON
splitter is determined as 1260~1650 nm which covers most of the optical bands.
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<strong>Uniformity</strong>
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Uniformity means the maximum insertion loss value between one input port and any
two output ports or between two input ports and one output port. This can ensure that
the transmission power at each <a href="https://www.ghcomms.com/plc-splitter/abs-
plc-splitter/">ABS PLC Splitter</a> output port is the same in a PON system to
simplify the network design.
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<strong>Directivity</strong>
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Directivity is the part of power transferred from one input port to another input
port or from an output port to another output port. For a 2xN optical splitter, when
light injects into one of the input ports, light doesn’t only propagate out of the
output ports. Some of the light propagates back through the second input port. And
when the light injects into one of the output ports, light propagates back through
the other output ports. In a bidirectional transmission system such as a PON,
directivity is useful to reduce signal crosstalk. A high directivity value will
increase the insertion loss due to the optical power loss.
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In FTTx and PON architectures, fiber optic splitter is an important component to
share the optic network with multiple users. The basic principle of fiber optic
splitter is to split one optic light beam into several parts at a certain ratio.
According to different manufacture technologies, fiber optic splitters can be divided
into PLC splitter and <a href="https://www.ghcomms.com/fbt-splitter/">FBT
Splitter</a>. You may wonder the differences of the two splitter types when making a
choice between them. This article aims at helping you to understand their
distinctions and make better decisions.
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<strong>What Is FBT Splitter?</strong>
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FBT, or fused biconic taper uses the traditional technology to fuse several
fibers together closely. Fibers are aligned by heating for a specific location and
length. Fusion process will not stop until the parameters of the fibers reach the
required standards. Since fused fibers are very fragile, they are protected by a
glass tube made of epoxy and silica powder. Then a stainless steel tube covers the
inner glass tube and is sealed by silicon. <a href="https://www.ghcomms.com/fbt-
splitter/abs-fbt-splitter/">ABS FBT Splitter</a> is also widely used for different
applications.
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