The Application of Optical Passive Components in WDM System

Based on the DWDM technology, the all-optical network make full use of fiber optic cables which have huge transmission capacity, it must be the next-generation high reliability, fast speed information network technology. Fiber optic attenuators are widely and important optical passive components, especially in the all-optical network.

Optical attenuator is applied into WDM system upstream and downstream node channel, power balance, EDFA gain flatness, optical communication lines, system evaluation, research and adjustments, correction and so on. It is in accordance with customers’ requirements by absorbing or reflecting off part of the optical power and then reduce the signal power as expectation. It’s position in the optical fiber network just shown in the figure.


Warm Tips:  TX – Transmitter                    RX – Receiver

                     WL – Wavelength Locker       MOD – Modem

                      FM –  Filtration Module       OXC – Optical Cross Connect

                      OADM – Optical Add Drop Multiplexer

In the WDM system, EDFA is a necessary component, it is quite important for achieving all-optical network communication. However, because of the limitation of gaining window ports for EDFA, it makes different wavelengths have different gain multiplier, it leaded to energy imbalance between the channels of a WDM sytstem. Then it will result in following three problems:

  • Received Energy imbalance will beyond the allowed dynamic range finally.
  • Accumulation of SNR imbalance can cause gain of a certain wavelength of BER, it may lower than the required BER (bit error rate).
  • Because of the shortage of the gain, the minimum signal power of the channel may be lower than the sensitivity of the receiver.

In the DWDM optical network which has multiple contact node, such as MAN, the transmission distances and the volume of the business between the different channels are different, each channel’s transmission must be balanced, including power, BER, signal to noise ratio and so on. The application of variable fibre optic attenuator is the first solution in the system.

Moreover, optical attenuators are also important for optical telecommunication link and the test for the system. Fiber optic cable link and the system need to be examined before laying them, then it can insure some performance parameters of the system or link road, so that it is easy to do some optimization test. So we need to simulate the actual situation, mainly the proper attenuation for the signal, then we will find out the actual situation after the long distance transmission.

Applications of Fiber Media Converter and some other Devices

We know, Networks usually need conversion from Multimode fiber to single-mode fiber, it supports longer distances than Multimode fiber. And multimode to singlemode media converter mode conversion is typically required when:

  • Network distance requirements exceed the limit of Multimode fiber.
  • Lower cost legacy equipment uses Multimode ports, and connectivity is required to Single mode equipment.
  • A building has Multimode equipment, while the connection to the Service Provider is Single mode.
  • Multimode equipment is in a campus building and Signle mode fiber is used between buildings

Fiber-to-fiber media converters can extend a Multimode network across Single mode fiber with distances up to 140km for Fast Ethernet (100Mbps) and 80km Gigabit Ethernet (1000Mbps). In this application, two Ethernet switches equipped with MM fiber ports are connected utilizing a pair of fiber-to-fiber converters which convert the Multimode fiber to Single mode and enable network connectivity across the distance between the switches. Fiber-Fiber Converters enable the extension of multimode to single mode or multimode to multimode fiber connections to distances up to 160km.

fiberstore fiber media converter

We can see the benefits of it. Convert Fast Ethernet or Gigabit multimode fiber to multi-mode or single mode fiber protect your investment in existing multimode fiber -based hardware. Connect different fiber types, distances and wavelengths across a variety of topologies and network architectures

Fiber to Fiber Media Converter models that are best suited for enterprise and Service Provider applications, offer an on-board processor to continuously monitor that both fiber connections are up. This functionality, generally referred to as “Link Pass-Through”, monitors the state of the link to the end devices and ensures that each end-point knows whether the entire link is up or not. Some media converter products do not have this intelligence and simply “nail up” the link even though the fiber link peer is down. With Link Pass-Through, a feature available in all Perle Fiber to Fiber Optic Converters, the network’s SNMP management system can be alerted when a fault occurs so that corrective action can take place.

Multimode to Singlemode Converters provide efficient solutions for interconnecting multimode fibre LANs over longer distances by integrating singlemode fibre optic cable into the LAN. The converter also enables Ethernet LAN and WAN connectivity, by providing a multimode interface to singlemode fibre carrier demarcation points. Models are available for singlemode to multimode conversion between Fast Ethernet devices, or for Asynchronous Transfer Mode (ATM) applications transported over a Synchronous Optical Network (SONET). Each Media Converter is enclosed in a compact, strong metal case and includes an external power supply for stand-alone applications.

Sometimes in the fiber optic network, people may need to reduce or balance the power of the light transmitted from one device to another device, fiber optic attenuators are used in such cases, they are able to control the output of the fiber light power level. Fiber optic attenuators are used for reducing the power of the light in the fiber optic network. Fiberstore supply different types fiber optic attenuators, if you want to know more, you can visit the attenuator category.

While adjustable fiber optic attenuator refer to the attenuator that can generate a adjustable Loss to the fiber optic link. Fiberstore’s fiber attenuator series include: SC, FC, LC, ST, MU,SC/APC, FC/APC, single mode fiber optic attenuator and multimode fiber optic attenuator available. Fiberstore’s variable fibre optic attenuator is manufactured according to international standard and are compatible with the fiber optic products currently available in the international market.

Fiber Attenuator

Well, excepr this, another fiber optic product is on hot sale in Fiberstore. It is optical amplifier. A fiber optic splitter is a device that splits the fiber optic light into several parts by a certain ratio. For example, when a beam of fiber optic light transmitted from a 1X4 equal ratio splitter, it will be divided into 4-fiber optic light by equal ratio that is each beam is 1/4 or 25% of the original source one. A fiber splitter (includes single mode fiber splitter and multimode fiber splitter) is different from WDM. WDM can divide the different wavelength fiber optic light into different channels. fiber optic splitter divide the light power and send it to different channels. And the splitter we divide it into different kinds, such as 1×2 fiber coupler,1×4 fiber coupler,1×8 fiber coupler, 1×16 fiber coupler,1×32 fiber coupler and so on.

Finally, yeah, you are right, as usual, there is a small tip, all the products I mentioned in this paper you can find in our Fiberstore, if you want to get it, click the link and get what you want. Thank you.