Why we need Bend insensitive fiber patch cord?

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Fiber patch cord is seeing broad adoption
in applications spanning telecommunication and data communication. With
numerous business and enterprise reaping great benefits from it, fiber patch
cord represents by far the most sufficient and prevalent bandwidth feeder. As
those gigabit-capable networks proliferate, the fueling capacity and speed
quest further drive fiber patch cord deployment. When facing various fiber
patch cord types on the market, how can we make a valid choice? Some basic
understanding of the fiber patch cord would be helpful.

 

What Is Fiber Patch Cord?

Fiber
patch cord, often called fiber
patch cable, fiber jumper, or fiber patch lead, is a length of fiber cable that
terminated with fiber optic connectors (LC, SC, MTRJ, ST and etc.) at each end.
The connectors allow fiber optic patch cord to be rapidly connected to an
optical switch or other telecommunications/computer device. Fiber jumper is a
key player for indoor use, like in server rooms or in data centers. Featuring
excellent reliability, superior adaptability, and improved security, fiber
patch cord has ranked the best choice for applications where conventional
copper cables fail to reach.

 

What Are Fiber Patch Cord Types and How
to Choose?

Fiber optic patch cords in the market
now have various types. We mainly divide them into common fiber patch cord
types and special patch cord types in this explanation.

 

Common Types of Fiber Patch Cords

Based on different specifications and
standards, the common fiber patch cords can be categorified from the
perspective of fiber cable mode, transmission mode, jacket type, connector
type, and polishing type.

 

Fiber Cable Mode: Single Mode or
Multimode

 

The mode of fiber patch cables
indicates how light beams travel within the fiber. There are two fiber cable
modes: single mode and multimode.

 

Single mode fiber patch lead only
allows one mode of light to pass along its length with a very thin diameter of
8-10 microns, thus it can carry signals at much higher speeds with lower
attenuation. Single mode fiber has two varieties: OS1 and OS2, which are
different in construction and application. In Comparison Between OS1 and OS2
SMF Cables, the differences between OS1 and OS2 are illustrated. In general,
OS1 and OS2 are both applicable for long-haul transmission but OS2 is more
suitable for long-haul transmission by offering better performance with fewer
losses.

 

The core of the multimode fiber patch
cord is bigger, typically 50 or 62.5 microns, which enables multiple light
modes to be transmitted. It comes in five varieties supporting different
transmission rates or distances: 62.5-micron OM1, 50-micron OM2, 50-micron OM3,
50-micron OM4, and 50-micron OM5, which can be differentiated by standard
jacket colors. Since multiple light paths travel down the cable, the distance
which multimode fiber jumpers can reach is usually short. For short-distance
transmission within a building or campus, multimode fiber patch cords are the
best-suited type. You can get more information about multimode patch cables in
Multimode Fiber Types: OM1 vs OM2 vs OM3 vs OM4 vs OM5.

 

Number of Fiber Strands: Simplex or
Duplex

 

According to the number of fiber
strands, there are simplex and duplex fiber patch cord. As shown in Figure 2,
simplex fiber patch cord contains one single strand of fiber with one simplex
connector on each end. It can be linked with a pair of BiDi transceiver modules
featuring with one port. Whereas duplex fiber patch cord consists of two
strands of glass or plastic with one duplex connector (or considered as two
simplex connectors). It is often linked with common transceivers or dual fiber
BiDi transceivers.

 

Jacket Type: PVC or LSZH

 

PVC and LSZH are used to describe the
common jacket material of fiber patch cord. Fiber patch cables covered with PVC
jacket are flexible at normal installation temperatures. Compared with PVC
patch cords, LSZH patch cords are more rigid and less flexible but they contain
the flame retardant compound that doesn’t emit toxic fumes if it burns. PVC
fiber optic patch cord is usually used for indoor applications such as
horizontal runs from the wiring center. While LSZH cable is used in
unventilated areas exposed to public, such as subways and tunnels and also used
for rooms that are not easy to get out quickly.

 

Connector Type: LC, SC, ST or Others

 

There are many connector types used in
fiber patch cables such as LC, SC, ST, MTP or MPO listed in this article How
Many Fiber Connector Types Do You Know? Aside from these connectors, there is a
latest connector design called MDC connector, which enables the highest
achievable connector density by delivering a 3X advantage over a standard LC
connector. The different connector types are to plug into different interfaces,
so you’d better affirm the interface type of the devices you are using the
first time.

 

If divided by the criteria whether the
connector on each side is the same, they can be divided into same-connector
type fiber patch cord and hybrid fiber patch cord. Fiber patch cords that have
the same type of connector on both ends includes LC to LC fiber patch cord, SC
to SC fiber patch cord and etc. While hybrid fiber patch cord has different
connectors on each end, like fiber patch cord LC to SC. If the port type of
devices on both sides are the same, you can choose the same-connector type
fiber patch cord, or you need choose the hybrid one.

 

Polishing Type: PC, UPC or APC

 

Fiber optic connectors are designed and
polished to different shapes to minimize back reflection, which is particularly
important in single mode applications. According to this connector polish
types, there are PC, UPC, and APC fiber patch cords. This post PC vs UPC vs APC
Connector: Selecting the Right Fiber Connector Type presents the difference of
PC, UPC, and APC. Nowadays PC polish type has been replaced by UPC type.
Whether you choose UPC or APC depends on your actual application. Since APC
provides less insertion loss than UPC, the APC fiber patch cables are more
applicable for high bandwidth applications and long-distance links, such as
FTTx, passive optical network (PON) and wavelength division multiplex (WDM).
Whereas UPC fiber patch cords apply to optical systems that are less sensitive
to insertion loss such as digital TV and telephony.

 

Special Types of Fiber Patch Cords

Fiber patch cord is evolving to keep
pace with the ever-increasing bandwidth needs. Some specially designed fiber
patch cables emerge to fit different application needs. Knowing the available
options would save us significant time and money. Here are some special fiber
optic patch cords for use in certain circumstances.

 

Armored Fiber Patch Cord

 

Armored fiber patch cord retains all
the features of the common fiber patch cord. The main difference between
armored fiber patch cable and common fiber patch cord is that armored fiber
jumpers are designed with a stainless armored tube inside the jacket and
outside the optical fiber as you can see in figure 4. This design enables
armored fiber patch cords strong enough to be anti-rodent and resist the steps
by an adult. Strong as it is, the armored fiber patch cord is actually as
flexible as standard fiber optic patch cord and can be bent randomly.

 

Bend Insensitive Fiber Patch Cord

 

Bend insensitive fiber patch cable is
highly resistant to bend related damage and loss. It has a small cable bending
radius and prevents additional bend losses by innovative core design and
enhanced low macro-bending sensitivity. Bend insensitive fiber patch cord is
made to support data center and FTTH applications, and high-density cabling
that has to wrap and take tight corners. Click to see why you need bend
insensitive fiber patch cables.

 

Mode Conditioning Fiber Patch Cord

 

This special fiber patch cord is a
duplex multimode patch cable that has a small length of single mode fiber at
the start of the transmission length. It is designed to solve the technical
issue involved in using single mode equipment on the existing multimode cable
plant. Mode conditioning fiber patch cord aims to drive the distance of
installed fiber plant beyond its original intended applications, as well as to
improve data signal quality. For more information about using tips of mode
conditioning patch cord in typical cases, please refer to Mode Conditioning
Patch Cord Utilized in 1/10 Gigabit Ethernet Applications.

 

Low Insertion Loss Fiber Patch Cord

 

The low insertion loss fiber patch
cords adopting LL technology feature lower connector insertion loss compared
with the common fiber patch cords, though it bears many similarities with
common patch cable judged only by appearance. For example, the
industry-standard insertion loss of common fiber connector is 0.75dB, but for
low loss fiber patch cord, it can be 0.2dB or lower. This type of fiber patch
cords is often used for applications where the amount of attenuation loss is a
crucial element. With reduced attenuation, they are able to expand the network’s
reach for long-haul applications.

 

Uniboot Fiber Patch Cord

 

Terminated with specially designed LC
uniboot connectors, uniboot fiber patch cable integrates two fibers in a single
cable, thus delivering significantly more advantages in high-density cabling
environments. It cuts down the cable count up to 50% compared with the standard
LC cables and represents the best fit for places where space is a concern,
which is the main advantage of it.

 

Conclusion

Fiber patch cord has helped many people
to achieve larger bandwidths and greater speeds, and the benefit of which is
stretching across a wide range of constructions. From the introduction of the
fiber patch cable types and their applications above, you may get some
illustration on which fiber jumpers to be chosen. The parameters of common
fiber patch cables such as fiber cable mode and connector types are the key
elements that matter a lot. If your cabling environment is rather demanding,
the special fiber patch cord mentioned above will fit your needs. Seeking help
from a professional is always the best choice to avoid losses when you find it
hard to make a decision.