#16 channels DWDM MUX/DEMUX

[qing-chloe-blog]

How to Realize 16 Channels Transmission in DWDM Network?

DWDM MUX/DEMUX plays a critical in WDM network building. 16 channels transmission is very common in DWDM networks. How to realize it in a simple way? This article intends to introduce two solutions to achieve 16 channels with different types of components. Which one is more cost-effective and competitive? The comparison between the them also will be explored. Hope it will help you when choosing fiber mux for your DWDM networks.

Solutions to Achieve 16 Channels Transmission in DWDM Network

In order to illustrate the solution more clearly, I take two types of DWDM MUX/DEMUX as an example. One is the traditional 16 channels dual fiber DWDM MUX/DEMUX. Another is two FMU 8 channels dual fiber DWDM MUX/DEMUX. The latter has an expansion port.

Solution One: Using Traditional 16 Channels DWDM MUX/DEMUX

The 16 channel DWDM MUX/DEMUX is a passive optical multiplexer designed for metro access applications. It’s built fiber mux and demux in one unit and can multiplex 16 channels on a fiber pair. In addition, this type of fiber mux also can be added some functional ports like expansion port, monitor port and 1310nm port, which make it possible to increase network capacity easily. The following is a simple graph showing the 16 channels transmission with this traditional DWDM MUX/DEMUX.

Solution Two: Using Two FMU 8 Channels DWDM MUX/DEMUX Modules

The FMU 8 channels DWDM MUX/DEMUX provide 8 bidirectional channels on a dual strand of fiber. Usually they are used together. Unlike the 16 channels DWDM MUX/DEMUX, this FMU 8 channels one has a more compact size, for it only occupies half space in a 1U rack. Put two FMU 8 channels DWDM MUX/DEMUX modules into one 1U two-slot rack mount chassis. two 8 channels DWDM MUX/DEMUX with different wavelengths are connected through the expansion port to realize 16 channels transmission in a DWDM network. Here is a graph showing how to achieve 16 channels DWDM transmission with these two 8m channels fiber muxes. As shown in the figure, two 8 channels DWDM MUX/DEMUX with different wavelengths are connected through the expansion port to realize 16 channels transmission in a DWDM network.

16CH DWDM MUX and Two FMU 8CH DWDM MUX: What’s the Difference When Deployed?

From the content above, we can see both solutions can realize the 16 channels transmission in a DWDM network. Then, are there differences between them? Or which is more competitive? Here is a simple analysis of the two solutions.

Firstly, comparing the two graphs above, the FMU 8 channels DWDM MUX/DEMUX are connected together by an expansion port, that’s why it can deliver 16 channels services like the traditional one. Except for connecting 8 channels DWDM MUX/DEMUX, the FMU fiber mux with expansion port also can be combined with other channels fiber mux like 2 channels, 4 channels or other channels, which offer more flexibility for optical network deployment and upgrade. And you can add DWDM into CWDM networks at some specific wavelengths with FS.COM FMU fiber mux.

Secondly, DWDM MUX/DEMUX price is always an important point that many network operators pay attention to. Therefore, when buying a fiber mux, the cost is a critical point to consider. If you search on Google, you will find the lowest price is $1100 in FS.COM. And the cost of using two 8 channels MUX/DEMUX is the same as the deployment of one 16 channels MUX/DEMUX. However, compared with the 16 channels DWDM MUX/DEMUX, the FMU 8 channels fiber mux provides a competitive solution for small networks which needn’t to buy a full-channel fiber mux that supports all 16 channels or more channels.

Conclusion

From the comparison above, the FMU 8 channels DWDM MUX/DEMUX is more flexible and cost-effective when deployed in WDM networks. How to choose is based on the requirements of your networks. FS.COM supplies two different types of these WDM MUX/DEMUX. Here is a simple datasheet of them. If you have more requirements for additional wavelengths, welcome to visit www.fs.com for more detailed information.

 Sources:http://www.fiber-optic-tutorial.com/16-channels-dwdm-mux-demux-in-dwdm-network.html

[optical-sintai]

DWDM Mux Demux

https://www.optical-sintai.com/products/dwdm-mux-demux/

01- 4CH DWDM Mux Demux

DWDM Mux Demux is usually used for long-haul transmission where wavelengths are packed tightly together over the C-band, up to 48 wavelengths in 100GHz grid(0.8nm) and 96 wavelengths in 50GHz grid(0.4nm).

 02- 8CH DWDM Mux Demux

The 8-Channel DWDM MUX-DEMUX module provides multiplexing and demultiplexing for up to 8 DWDM wavelengths in a single-wide module. All wavelengths fall within the pass-band of a C band channel, allowing the module to be used in DWDM applications to increase the number of wavelength circuits.

 03- 16CH DWDM Mux Demux

16 Channels Double Fiber Passive 100 GHz DWDM Mux/Demux is a member of the sentai Optics DWDM Series product line. We designed Sintai Optics DWDM Series products to allow easy, gradual, logical, and cost-efficient expansion of network bandwidth using industry-leading passive WDM technology.

 04- 18CH DWDM Mux Demux

The DWDM multiplexer/demultiplexer launched by Guangzhou Sintai Communication Co., Ltd. is designed for multi-wavelength DWDM network applications. It works on an ITU grid with 100 GHz channel spacing based on thin-film filter (TFF) technology.

[yourmellyguostuff-blog]

How to Realize 100KM DWDM Network With FMT 4000E

Nowadays, DWDM technology has been one of the most commonly used technology in optical transport network (OTN) applications due to the increasing bandwidth need of telecommunication providers. Faced with unpredictable traffic requirements and increasing bandwidth demands, FS has developed a new standardized optical transport solution, which called FMT WDM transport platform. And this FMT WDM transport platform  is divided into four specific series according to different transmission distance, including CWDM solution FMT 1800, DWDM solution FMT 1600E, 4000E, 9600E. In this post, we will take FMT 4000E optical transport platform as an example to illustrate how does this transport platform realizes 100km network connections and its advantages.

What Is FMT 4000E DWDM Network Transport Platform?

As mentioned above, FMT 4000E DWDM network transport platform is one type of the FMT WDM transport platform series. This optical transport platform is a 4U managed chassis. It is equipped with 16 full-size slots and optical layer modules and a wide range of intelligent services modules can be installed in these slots. Equipped optical devices in FMT 4000E will be illustrated in detail in the following part.

Currently, FS has developed two versions FMT 4000E, but these two versions has different transmission. One version can support 160km transmission, while another can support 100km transmission. And this post will focus on FMT 4000E for 100km. This platform can achieve 100km end-to-end dual fiber bidirectional transport and support up to 40 wavelengths from C21-C60 at 100GHz. In addition, this optical transport platform can be applied in metro/regional networks, such as CATV, FTTH/PON, xDSL triple play services, GSM/3G mobile services, business customers storage services and so on.

How Does the DWDM Network Work By Using FMT 4000E

From the above topology, we can find that the optical signal from the switch will be sent to 40CH DWDM MUX DEMUX at Site A for wavelength division multiplexing. And then the optical power will be lowered by using optical attenuator. And the dispersion will be compensated by DCM. When this process is finished, the booster amplifier (BA) will improve the optical power and extend the transmission distance. After 100km fiber transmission, we need to amplify the signal by using pre-amplifier (PA) and then the optical signal will be compensated by DCM again. At this time, the optical signal will be sent to 40CH DWDM MUX DEMUX at Site B for demultiplexing again. Finally, the optical signal will be sent to the switch.

Why Choose This FMT 4000E DWDM Transport Platform？

This FMT 4000E DWDM transport platform has flexible networking because it is equipped with intelligent DWDM MUX/DEMUX, integrated with DWDM EDFA and DCF-based DCM system management. This platform has high channel density because it has up to 40 DWDM channels. And this platform can achieve 100km end-to-end dual fiber bidirectional transport when the fiber link loss is 0.25dB/km and the fiber type is G.652D. In addition, this platform has monitor online management software, which can allow operators and administrators to monitor the performance of the whole network. When the urgent accident occurs, this network management system can notify the user so as to ensure the safety of the network. This system can also provide real-time management for local and remote network. Besides, it will send email to inform you of the performance of the network.

Conclusion

This FMT 4000E optical transport platform will be a cost-effective option for l00km transmission due to its better network performance and centralized network management. And FS is always striving for meeting your specific needs and this product is customized for each customer. If you are interested in this product, please contact us via sales@fs.com.

[shinenewsposts-blog]

FS.COM 2017 – A Year Full of Gratitude and Appreciation

2018 is coming. At the end of 2017, Cable Gland with Strain Relief  FS.COM has reviewed the whole year and concluded a keyword “innovation and development”. In 2017, we continuously improve product quality and perfect service system to ensure products meet and exceed customer requirements. For instance, FS.COM FMT (multi-service transport) system is engineered to support low-cost 100G DWDM solutions for high-capacity optical links and conducive to save cabinet space. And on the basis of FHD (high-density) cable managing system, we self-developed the FHX system for ultra high-density cabling with easy management of MAC of connections in data centers as simple as plug & play.

In addition, FS.COM has completed the other product system like network switches, 25G transceivers & DAC/AOC, etc. With one year’s hard work, we got many positive comments from industry participants. Here just presents parts of the comments.There is a risk of buying network switches from vendor you haven’t used before or without feedback or recommendations from other people. However, you bought, and FS.COM didn’t let you down. FS.COM offers multiple types of optical transceivers ranging from SFP, SFP+, QSFP+ to 100G QSFP28 optics.

And every transceiver optics is individually tested on corresponding equipment to ensure its full compatibility on your devices. Moreover, we have different types of fiber cables and copper cables to meet various network demands.Last year, we built our USA warehouse to reduce the delivery time and this year, we have built the Germany warehouse and are expanding the European market. The following picture is one of our customers showing the transceiver optics and patch cables on Twitter. CWDM and DWDM Mux/Demux are used to increase the bandwidth of an optical fiber by multiplexing several wavelengths onto it, thus saving valuable optical fibers. We have CWDM Mux/Demux with 4 channels, 8 channels and 18 channels, and DWDM Mux/Demux with 8 channels, 16 channels, 40 channels and 96 channels, which can meet most network demands.

[gigalightoptics-blog]

CWDM and DWDM Comparison: What’s the Difference?

DWDM (Dense Wavelength Division Multiplexing) is undoubtedly the popular technology in today's optical fiber applications. However, because of its expensive price, many operators without enough money are quite hesitated to use it. Can we use wavelength division multiplexing at a lower cost? Faced with this demand, CWDM (Coarse Wavelength Division Multiplexing) came into being. And in the post, we will take an introduction on the main difference between CWDM and DWDM and which one is your better choice.

CWDM, as the name suggests, is a DWDM close relative. When comparing CWDM vs. DWDM, their differences are mainly two points as follows:

1. CWDM carrier channel spacing is wide, so the same fiber can only reuse 5 to 6 or so wavelength. This is why we call “Dense” and “Coarse”.

2. CWDM modulates laser by using non-cooling laser, but DWDM is used to cooling laser. The cooled laser is thermally tuned and the non-cooled laser is electronically tuned. Since the temperature distribution is very uneven in a wide wavelength range, the temperature tuning is difficult and costly to achieve. CWDM avoids this difficulty, therefore the cost is significantly reduced, the entire cost of CWDM system is only 30% of DWDM.

CWDM provides very high access bandwidth for low cost, and is suitable for popular network structures such as point-to-point, Ethernet, SONET ring, especially for short distance, high bandwidth, and point-intensive communication applications. Building communication between buildings or buildings. In particular, it is worth mentioning that CWDM and PON (passive optical network) with the use. PON is an inexpensive, point-to-multipoint optical fiber communication method. By combining with CWDM, each individual wavelength channel can be used as the virtual optical link of PON to realize the broadband data transmission between the central node and multiple distributed nodes.

At present, several companies are introducing CWDM-related products. Here we mainly introduce CWDM Mux/Demux and DWDM Mux/Demux.

(1). CWDM Mux/Demux Module:

CWDM Mux and CWDM Demux are designed to multiplex multiple CWDM channels into one or two fibers. The core of CWDM Module application is the passive MUX DEMUX unit. The common configuration is 1×4, 1×8, 1×16 channels. Available in 19″ Rack Mount or LGX module package, optional wide band port is available to multiplex with CWDM Channels wavelength.

(2). DWDM Mux/Demux Module:

DWDM Mux and DWDM DeMux are designed to multiplex multiple DWDM channels into one or two fibers. The common configuration is 4, 8, 16 and 40 channels. These modules passively multiplex the optical signal outputs from 4 or more electronic devices, send them over a single optical fiber and then de-multiplex the signals into separate, distinct signals for input into electronic devices at the other end of the fiber optic link.

However, CWDM is the product of cost and performance compromise; inevitably there are some limitations on performance. Industry experts pointed out that CWDM currently exist below the following four points: First, CWDM in a single fiber to support the number of multiplex wavelengths less, resulting in higher cost of expansion in the future; second, multiplexers, multiplexers, etc. The cost of the equipment should be further reduced, these devices can not only DWDM corresponding equipment, a simple modification; Third, CWDM does not apply to metropolitan area networks, metro nodes between the shorter distance, operators in the CWDM equipment expansion on the money can Used to lay more fiber optic cable, get better results; Fourth, CWDM has not yet formed a standard.

From the CWDM and DWDM comparison above, we can know both the benefits and drawbacks of CWDM and DWDM.  If the transmission distance is short and cost is low, then CWDM may be your first choice. On the contrary, you can consider DWDM. For more information about CWDM and DWDM, you can visit: Gigalight.

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Comparison Between CWDM & DWDM Technology

by Fiber-MART.COM

For a better signal transmission in fiber-optic communication, different kinds of technologies are applied to the industry. Wavelength-division multiplexing (WDM) is one of the commonly used technologies which multiplexes a number of optical carrier signals onto a single optic fiber by using different wavelengths of laser light. That is to say, WDM enables two or more than two wavelength signals to transmit through different optical channels in the same optical fiber at the same time.

In the WDM system, there are two types of divisions –

CWDM

(coarse wavelength division multiplexing) and DWDM (dense wavelength division multiplexing). They are both using multiple wavelengths of laser light for signal transmission on a single fiber. However, from the aspects of channel spacing, transmission reach, modulation laser and cost, CWDM and DWDM still have a lot of differences. This article will focus on these distinctions and hope you can have a general understanding about CWDM and

DWDM

technology. Channel SpacingAs their names suggest, the words “coarse” and “dense” reveal the difference in channel spacing. CWDM has a wider spacing than DWDM. It is able to transport up to 16 wavelengths with a channel spacing of 20 nm in the spectrum grid from 1270 nm to 1610 nm. But DWDM can carry 40, 80 or up to 160 wavelengths with a narrower spacing of 0.8 nm, 0.4 nm or 0.2 nm from the wavelengths of 1525 nm to 1565 nm (C band) or 1570 nm to 1610 nm (L band). It is no doubt that DWDM has a higher performance for transmitting a greater number of multiple wavelengths on a single fiber. Transmission ReachSince the wavelengths are highly integrated in the fiber during light transmission, DWDM is able to reach a longer distance than CWDM. The amplified wavelengths provide DWDM with the ability of suffering less interference over long-haul cables. Unlike DWDM system, CWDM is unable to travel unlimited distance. The maximum reach of CWDM is about 160 kilometers but an amplified DWDM system can go much further as the signal strength is boosted periodically throughout the run. Modulation LaserCWDM system uses the uncooled laser while DWDM system uses the cooling laser. Laser cooling refers to a number of techniques in which atomic and molecular samples are cooled down to near absolute zero through the interaction with one or more laser fields. Cooling laser adopts temperature tuning which ensures better performance, higher safety and longer life span of DWDM system. But it also consumes more power than the electronic tuning uncooled laser used by CWDM system. CostBecause the range of temperature distribution is nonuniform in a very wide wavelength, so the temperature tuning is very difficult to realize, thus using the cooling laser technique increases the cost of DWDM system. Typically, DWDM equipment is four or five times more expensive than CWDM equipment. ConclusionCWDM and DWDM are both coming from the WDM technology that is capable of conveying multiple wavelengths in a single fiber. But with different characteristics, people should think twice before choosing the CWDM or DWDM system. CWDM usually costs less but its performance is far behind DWDM. Both your requirements and budget need to be taken into consideration. Moreover, the WDM products including CWDM mux/demux module, DWDM mux/demux module and

optical splitter

are highly welcome in the market.

[dkphotonics]

WDM And The Modules Based On It: The Need Of The Hour

In fiber-optic world of communication, wavelength-division multiplexing or WDM is an innovation which multiplexes various optical transporter signals onto a solitary optical fiber by utilizing distinctive wavelengths, that is the shades of the laser light. This system empowers bidirectional interchanges in more than one strand of fiber, and also increases the limits and domains of it. The term wavelength-division multiplexing is generally connected to an optical transporter, which is normally depicted by its wavelength, though recurrence division multiplexing is commonly applied to a radio bearer which is all the more of a frequently portrayer by recurrence. This is a simple convention since wavelength and recurrence convey a similar data.

How a WDM system works:

A WDM framework utilizes a multiplexer at the transmitter to combine the few signs and a demultiplexer at the collector to part them separated. Hence, WDM Mux and DeMux Modules are made to be used with the correct kind of fiber as it is conceivable to have a gadget that does both all the while, and can work as an optical add-drop multiplexer. The optical filtering gadgets utilized have ordinarily been etalons or to say, stable solid-state single-frequency Fabry–Pérot interferometers in the form of a thin-film-covered optical glass.

Need of WDM Multiplexing:

Since the physical fiber optic cabling is costly to actualize for every single company independently, its ability development by utilizing a Wave Division Multiplexing (WDM) is the need of the hour. WDM innovation was created to extend limits of single fiber systems can give. A WDM framework utilizes a Multiplexer at the transmitter to join a few wavelengths together; thus each one conveys diverse flag and signals via a demultiplexer at the recipient to make them separated. Both Mux and Demux are latent parts of the circuit, as their requirement of power is nil.

Types of WDM available:

These days there are a few sorts of institutionalized WDM in availibility:

General WDM, for example, 980/1550 WDM, 1310/1550 WDM.

CWDM incorporates CWDM mux/demux module and CWDM OADM module. The normal setup of CWDM mux/demux module is 2CH, 4CH, 8CH, 16CH, 18CH CWDM mux/demux module. Single fiber or double fiber association for CWDM Mux/demux are accessible.

DWDM incorporates 50GHz, 100GHz, 200GHz DWDM mux/demux module and DWDM OADM module. The normal arrangement is 2CH, 4CH, 8CH, 16 CH, 32CH, 40CH channels.

They are accessible as Plastic ABS module tape, 19'' rack mountable box or standard LGX box. What's more, regardless of what sort of connectors, as FC, ST, SC, LC and so on, all is available on DK Photonics, and they additionally can blend connector on one gadget. DK Photonics Technology Limited is one of the main organizations in outlining and assembling of fantastic optical inactive parts primarily for media transmission, fiber sensor and fiber laser applications. Headquarter and manufacturing plant is situated in Shenzhen of China. Savvy, best quality and best administration are forever their objective. So if you have any requirement regarding the WDM or any of the devises based on it, DK Photonics is the reliable and trusted brand!

[qing-chloe-blog]

How to Calculate Power Budget and Link Distance in CWDM Network

By multiplexing separated wavelengths from multiple ports onto a single fiber in the network, coarse wavelength division multiplexing (CWDM) network increases fiber capacity at a low cost. And all the CWDM components are passive and do not need power, which requires lower investment than DWDM networks and make it popular. This article intends to explore how to calculate the power budget and link distance in CWDM network, offering more conveniences for your CWDM network deployment.

Understand Optical Power Budget in CWDM system

One important factor of network design, including various optical networks like DWDM and PON, is the optical power budget. Optical power budget is the amount of light available to make a fiber optic connection. The difference between the output power of the transmitter and the input power requirements of the receiver is referred to as the power budget. The power budget with various losses in an optical fiber, as shown in the picture below, is obtained by first determining the optical power emitted by the source, usually expressed in dBm, and subtracting the power (expressed in same units, e.g., dBm) required by the detector to achieve the design quality of performance (Receiver Sensitivity). Here is a common equation that can be used to calculate the power budget in a decided length fiber link.

Link Power Budget = Min Transmit Power - Min Receiver Sensitivity

Calculate Power Budget in CWDM Network

When designing a CWDM network, power budget is often used to determine the maximum distance that a link can support. The transmission power budget is the difference between the optical transmitter output power and the receiver sensitivity. In order to explain the calculation process clearly, all the equations will be given an example for illustrating.

Power Budget = Tx Power - Rx Sensitivity.

Example one. A -2 dBm optical transmitter and a -25 dBm receiver provide a total transmission power budget of 23 dB.

Power Budget = Tx Power - Rx Sensitivity = -2 dBm - (-25 dBm) = 23 dB

As we all know, in a CWDM system, CWDM Mux/Demux, CWDM OADM and other components are common. And each one of them will introduce loss once added into the CWDM system. For example, when using a CWDM OADM in CWDM network, the point where a channel is dropped, added, or passed will cause a loss of signal strength. Therefore, when calculating power budget for a CWDM link, all losses must be added together. As shown in the following equation.

Power Budget = Tx Power - Rx Sensitivity - Losses

Example two. Here is a link A shown as below. There are four CWDM Mux/Demuxes and two CWDM SFP transceivers in this link. The Mux/Demux #1 and Mux/Demux #4 are 8-channel CWDM Mux/Demux. The left two is 4-channel CWDM Mux/Demux. Link A is the distance from CWDM SFP #1 and CWDM SFP#4. Each CWDM Mux/Demux has a low insertion loss. For instance, the insertion loss of the 8-channel CWDM Mux/Demux is less than 3.1dB (including connectors and adapters).

Here is the calculating process.

Power Budget = Tx Power - Rx Sensitivity - Losses

Tx Power = 2 dBm

Rx Sensitivity = -23 dBm

Losses = (8-channel Mux/Demux #1 loss) + (4-channel Mux/Demux #2 loss) + (4-channel Mux/Demux #3 loss) + (8-channel Mux/Demux #4 loss)

= 2.5 dB + 2.0 dB + 2.0 dB + 2.5 dB = 9.0 dB

Power Budget = Tx Power - Rx Sensitivity - Losses = 2 dBm - (-23 dBm) - 9.0 dB = 16 dB

Calculate Maximum Link Distance in CWDM Network

After determining the power budget for a fiber link, we can use the value to calculate the maximum distance that the link can support. The calculation equation is shown as below.

Power Budget = Buffer Distance/Fiber Attenuation

Usually, a buffer of 2 dB is subtracted from the power budget to account for other factors that may affect the loss of transmission power. These factors include fiber aging, temperature, poor splice, etc. Fiber attenuation is the loss of signal strength as it travels through the fiber. The attenuation varies with the wavelength. Typical values are 0.2 to 0.35 dB/km.

Then we will calculate the maximum supported distance of link A in example two. Here we take the worst value for the fiber attenuation. The distance is:

Distance = (18 dB-2 dB)/0.35dB/km = 40km

The maximum supported distance of link A is 40km.

Summary

Knowing how to calculate the power budget and transmission distance can help engineers estimate the CWDM network deployment cost, and also can avoid some unnecessary problems in network design. This post gives a clear illustration to calculate them. Hope it would help you. In addition, FS.COM is a professional manufacturer and supplier of optical components. If you have any need, welcome to visit our website www.fs.com.

Sources:http://www.fiber-optic-components.com/calculate-power-budget-link-distance-cwdm-network.html

[katherinewangfs-blog]

Choose the Right SFP+ Transceivers for CWDM Mux Demux

Nowadays, CWDM technology is very popularly used as a easy and economical way to extend the network capacity by carrying several signals with different wavelengths through a signal fiber. If your network capacity is not enough for your daily use, deploying a CWDM system is an ideal choice for you. As the CWDM Mux Demux should be finally linked with the switches in a completed CWDM system, the fiber patch cable and 10G CWDM SFP+ transceiver are required to finish the whole CWDM link. Hence, this paper will mainly introduce the CWDM Mux Demux and choose the right CWDM SFP+ transceivers for the CWDM Mux Demux, which may be helpful for you to fast build a CWDM system.

CWDM Mux Demux–Key Component for CWDM System

CWDM Mux Demux is a key component for CWDM system, which should work in pairs. As an optical module, it can act as a multiplexer or demultiplexer at either end of the fiber cable. This kind of optical Mux Demux is much easier to use than the DWDM Mux Demux, but can not support the network as long as that of the DWDM Mux Demux. In general, it can offers several kinds of wavelengths, usually from 1270nm to 1610nm (20nm spacing), to support the signal transmission at lengths up to 80 km. Meanwhile, the CWDM Mux Demux can be designed with 4 channels, 8 channels, 9 channels, 16 channels and 18 channels for transmitting different amount of signals. To better know how does this kind of WDM Mux work, the following figure offers a reliable 4 channel CWDM Mux Demux duplex transmission design.

From the figure above, we can learn that two CWDM Mux Demux are connected by a length of duplex patch cable, and they are designed with four channels multiplexing the 1470nm, 1490nm, 1510nm and 1530nm over the same fiber. To complete the transmission link, four pairs of CWDM SFP+ transceivers with 1470nm, 1490nm, 1510nm and 1530nm TX and RX should be separately inserted into the ports of these two WDM Mux Demux. When the CWDM system works, the four different signals from the left to the right will be multiplexed in the CWDM Mux, transmitted over the duplex fiber and demultiplexed in the CWDM Demux, and vice versa for the signals from the right to the left.

How to Choose the CWDM SFP+ Transceivers for CWDM Mux Demux?

As mentioned above, the CWDM SFP+ transceivers are required for building a CWDM system which should be correctly inserted into the SFP+ ports of the CWDM Mux Demux. Thereby, here offers three factors that should be taken into consideration when choosing the CWDM SFP+ transceivers for the CWDM Mux Demux.

The first factor is the working wavelengths of the CWDM SFP+ transceivers. In order to ensure the CWDM system performance, the SFP+ transceiver working wavelengths should be the same to the SFP+ ports of the CWDM Mux Demux. Just like the first figure, when the working wavelengths of the first pair of CWDM SFP+ transceivers are 1470 nm, the first ports of the two CWDM Mux Demux should be also 1470 nm, so that the signal with 1470 nm can be successfully transmitted in the CWDM system. As the CWDM working wavelengths are available from 1270 nm to 1610 nm and the channel spacing is 20 nm, there are 18 kinds of working wavelengths for CWDM SFP+ transceivers, as shown in the following figure.

The second factor is the compatibility of the CWDM SFP+ transceivers. As the third party transceivers are more cost effective than the original one, the former kinds are always the choices for most users. However, the users are always unassured about the quality and compatibility of the third party transceivers for their low price. Here FS.COM is recommendable who offers the CWDM SFP+ transceivers fully tested on most famous original brand switches like Cisco, Brocade, Juniper and Arista. FS.COM CWDM SFP+ transceivers are less expensive but can perform as well as the original branded transceivers, without the compatible issue.

The third factor is the transmission distance the CWDM SFP+ transceivers can support. Although the CWDM system can not support the transmission as long as the DWDM one, it still can reach the lengths 80 km. At present, 10G CWDM SFP+ transceiver can be available at lengths of 20km, 40km, 60km, 80km or even longer on the market. Hence, you can also choose the CWDM SFP+ transceivers according to the transmission distance you system needs.

Conclusion

Building a CWDM system for carrying more data signals is a good choice if the existing network has insufficient capacity. To ensure the performance of the whole CWDM link, it is necessasry to choose the right CWDM SFP+ transceivers for the CWDM Mux Demux. From this paper, it can be concluded that there are mainly three factors, the working wavelength, the compatible issue and the transmission distance the CWDM SFP+ supports, should be taken into account when making the decision about which kind of CWDM SFP+ should be selected for the CWDM Mux Demux.

[amiable-aria-blog]

Hybrid CWDM-DWDM System Boosts Your Network Capacity

Should I choose a medium capacity but more cost-effective CWDM solution, or to adopt the cost-prohibitive DWDM approach with comparably enhanced capacity? This is a problem that consistently faced by WDM technology users. The wrong decision, however, may inevitably lead to bandwidth shortage or even potential bankruptcy derived from unnecessary capacity investment. This article introduces the hybrid CWDM-DWDM solution that combines both CWDM and DWDM technologies within a single system, helping decrease costs and simplify installation while maintain the flexibility to upgrade.

Hybrid CWDM-DWDM System Explanation

Hybrid CWDM-DWDM system utilizes the technology to merge DWDM and CWDM traffic seamlessly at the optical layer. Which allows carriers to add many channels to networks originally designed for the more limited CWDM capacity and reach. In other words, hybrid CWDM-DWDM system is used to empower CWDM system by integrating CWDM and DWDM equipment. Hybrid CWDM-DWDM system deliver true pay-as-you-grow capacity growth and investment protection. It offers a simple, plug-and-play option for creating hybrid system of DWDM channels interleaved with existing CWDM channel plans.

Benefits of Hybrid CWDM-DWDM System

Hybrid CWDM-DWDM system typically provides three benefits for carriers and users:

Reduced Cost: CWDM is more cost-effective than DWDM due to the lower cost of lasers and the filters used in CWDM modules. This cost saving becomes quite significant for large deployments.

Pay-As-You-Grow: Adding one new channels at a time allows for on-demand service introduction with minimal initial investment—a critical feature in terms of reduced OPEX and CAPEX spending.

Investment Protection: Carriers and end-users need always to bear the future growth in mind. With hybrid CWDM-DWDM system, carriers no longer have to choose between CWDM and DWDM—both options can be deployed simultaneously or as part of future growth. This module can be used in either CWDM or DWDM system. Current capital investment can always be used in the upgraded network.

How to Deploy Hybrid CWDM-DWDM System

The CWDM wavelength grid typically has 16 channels spacing at 20 nm intervals, with 8 channels (1470 nm-1610 nm) of them are most commonly used. Within the pass band of these channels, it is capable of adding 25 100 GHz spaced DWDM channels under the 1530nm envelope and 25 more under the 1550nm envelope. However, it is not so practical to add 25 DWDM channels in the pass-band of both the 1530nm and 1550nm CWDM channels. DWDM filter technology does allow 38 additional channels to clear the CWDM archway, which is shown as following.

To add more DWDM channels to the MUX side of the conventional CWDM system, one need to plug in a DWDM MUX with the appropriate channels under the pass band of the existing CWDM filters. The picture below illustrates the configuration of a CWDM system upgraded with 38 additional 100 GHz spaced DWDM channels. This hybrid CWDM-DWDM system consists of 38 DWDM channels and the existing 6 CWDM channels. The equipment required to go from the first architecture to the second are 2 DWDM MUX/DEMUXs, as well as the additional transmitter and receiver pairs. The additional loss incurred by the upgrade is equal to the additional loss of the DWDM elements and the additional connection points.

Flexible Hybrid CWDM-DWDM System Solution by FS.COM

The most vital elements concerning hybrid CWDM-DWDM system are the CWDM MUX/DEMUX and DWDM MUX/DEMUX. FS.COM developed and introduces FMU series products to facilitate installation and operation of WDM MUX/DEMUX. The prominent feature of this series products is that they combine the MUX/DEMUX into half-U plug-in modules, which can be installed in a 1U rack. As for hybrid CWDM-DWDM system, a FMU CWDM MUX/DEMUX and a DWDM half-U plug-in module can be installed together in a FMU 1U rack chassis, facilitating connections of these two modules while allowing for better cable management and network operation in hybrid CWDM-DWDM system.

Conclusion

Hybrid CWDM-DWDM system generally offers a cost-effective and future-proofing approach for service providers and end-users, by overcoming the obstacles faced by users of WDM technology today, providing a starting platform that scales smoothly and protecting the investment. A user can commence with the more cost-effective CWDM technology and then later add DWDM in the when the capacity is required. FS.COM FMU series WDM solution makes the process even easier and more flexible. For more information, please visit www.fs.com or contact sales@fs.com.

Source: http://www.fiber-optic-solutions.com/hybrid-cwdm-dwdm-boost-network-capacity.html

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Examples of CWDM Network Deployment Solution

Based on the same concept of using multiple wavelengths of light on a single fiber, CWDM and DWDM are two important technologies in fiber optical communications. As we all know, although the transmission distance of CWDM network is shorter than that of DWDM, it costs less and has the scalability to grow fiber capacity as needed. This article intends to give a simple introduction of components in CWDM networks and to explore some examples of CWDM network deployment cases.

Common Components Used in CWDM Networks

CWDM Mux/Demux

CWDM Mux/Demux, which is based on the film filter technology, is the basic component in CWDM networks. It can combine up to 4, 8 or 16 different wavelength signals from different fiber extenders to a single optical fiber, or it can separate the same wavelengths coming from a single CWDM source. That’s why CWDM can extend existing fiber capacity.

CWDM OADM (Optical Add-Drop Multiplexer)

A CWDM OADM is a device that can add (multiplex) and drop (demultiplex) channels on both directions in a CWDM network. It can add new access points anywhere in CWDM systems without impacting the remaining channels traversing the network. With this ability of OADM, the access points can be added to liner, bus, and ring networks, where the dual direction ring design provides redundant protected architecture.

CWDM Optical Transceiver

Optical transceiver is a necessary element in optical networks. And CWDM optical transceiver is a type of module supporting CWDM network application with CWDM wavelengths. When connected with CWDM Mux/Demux, CWDM transceiver can increase network capacity by allowing different data channels to use separate optical wavelengths (1270nm to 1610nm) on the same fiber. And the common CWDM transceiver type is SFP, SFP+, XFP, XENPAK, X2, etc.

CWDM Network Deployment Solution

Example One

Description: there are five buildings (Sheriff, Courthouse, Admin, Police & Fire, & Public Works) connected via multimode fiber cables (MMF) or single mode fiber cables (SMF). These buildings are linked via multimode SFPs in an existing D-link switches to create one network for internal use of the city offices. Below is a simple graph to show the situation.

Requirements: the goal is to install a single mode fiber network in town to connect numerous buildings. Some of these buildings have access to the city LAN. The Public Works building need to connect with Youth & Recreation Center, Library, Immanuel Lutheran School and the Senior Center. And all these buildings should have unfiltered Internet. Besides, the Waster Water Treatment Plant should be connected passing through the Senior Center. All these services are achieved using CWDM technology.

Solution: according to the requirements, this is a CWDM networks with several buildings to connect with. Here is the solution diagram.

In the diagram above, we can see there is an 8CH CWDM Mux/Demux connected with the switches. According to the requirements, Youth & Recreation Center, Library, Immanuel Lutheran School and Senior Citizen Center should be connected with the Public Works and need unfiltered services. Therefore, a 4CH CWDM OADM is placed after the CWDM Mux/Demux. Then the four wavelengths will be drop and into the four buildings. In addition, another CWDM OADM is deployed in Senior center to connect the Waster Water Treatment Plant, to meet the requirement. And each site also needs to use CWDM optical transceivers.

Example Two

Description: on site A, there are three Ethernet switches and a T3 router. And their working wavelengths 1470nm, 1490nm, 1510nm, 1530nm and 1610nm. Other three sites B, C, and D also have three Ethernet switches. And a T3 router is in site E. As the following figure shows.

Requirements: Considering the cost, all the wavelengths should be transmitted on a single fiber using CWDM technology.

Solution: according to the requirements, here is a simple diagram showing the solution.

In order to save cost, a 4CH CWDM Mux/Demux is used to multiplex four wavelengths (from three switches and one router) into one single fiber. At the first site B, a 1CH CWDM OADM is installed to remove one wavelength which is associated with network B. And other three sites are the same—dropping one wavelength associated with corresponding switch or router.

Summary

This article mainly introduces two CWDM network deployment examples. All the components like the CWDM Mux/Demux, CWDM OADM and CWDM transceiver are available in FS.COM. If you are interested in them, please contact us via sales@fs.com.

Related article:Differences between CWDM and DWDM

Sources:http://www.fiber-optic-components.com/examples-cwdm-network-deployment-solution.html

[katherinewangfs-blog]

Single Fiber Solutions for CWDM and DWDM Networks

It is well known that there are two transmission ways for fiber optical network, single fiber transmission and dual fiber transmission. From the name, it is easy to learn that the fiber amount is the main difference of these two transmission ways. For the dual fiber transmission, there should be totally two optical fibers, one for transmitting signals, and the other for receiving signals. But for the single fiber transmission, it only requires one optical fiber that can transmit and receive signals at the same time. This feature makes the network deployment easier and the network deployment cost lower than that of dual fiber one, especially in WDM network deployment. In this paper, it will mainly introduce the single fiber solution and its applications in CWDM and DWDM networks.

Single Fiber Solution

Single fiber solution can be also called bidirectional (BiDi) solution designed for carrying signals in both sides of one optical fiber simultaneously. When the single fiber network runs, the signals transmitted from the two sides feature different wavelengths to ensure the dual way transmission. Compared to the dual fiber network, the easy-to-deploy single fiber network would be a good choice for those who have limited budgets but need for bigger network capacity. As for its application, it is very popularly used in Point to Point, Ring or linear Add and Drop, where installing new fibers is impracticable or uneconomical. It can be also used for promoting the reliability of an existing dual fiber network, in which there are one optical fiber for work and the other one for protection.

Single Fiber CWDM Network

The single fiber CWDM network enables the signals with different wavelengths to be transmitted through a signal fiber, which results in a network capacity boost in metro and access networks. As each signal beam can be carried via different channel independently, the different data rates and protocols (T1, T3, Ethernet, Serial, etc) can be transmitted for the different users or applications. To better know how does the single fiber CWDM network work, here offers a figure that shows a 8 channel single fiber CWDM network design.

From the figure, we can learn there are two 8 channel CWDM Mux Demux connected by a single fiber for transmitting 16 signals with different wavelengths and the 16 wavelengths are divided into 8 pairs for bidirectional transmission. On the site A, 8 wavelengths are used for transmitting signals and others for receiving signals. While on the site B, the wavelengths for the TX and RX on the CWDM Mux Demux are all reversed to ensure the performance of the single fiber CWDM network. For instance, the 1270 nm on the site A is the first transmitting wavelength but the first receiving wavelength on the site B. As a result, the signal with 1270 nm can be totally transmitted from site A to site B via the single fiber.

Single Fiber DWDM Network

The single fiber DWDM network also takes full use of the wavelength division multiplexing technology that can greatly expand the capacity over the existing optical network, especially for the long transmission network. Compared to the CWDM one, it can be designed with more channels for larger data signals and can support the network with a much longer distance. What’s more, if the transmission distance is too long, the optical amplifier can be used to enhance the signals. On the other hand, all these advantage makes the cost to deploy a single fiber DWDM network much higher than the CWDM one. Besides, here offers the figure of a single fiber DWDM network design for your reference.

The figure shows a complicated a single fiber DWDM network design that uses two 8 channel DWDM Mux Demux in the main link for single fiber transmission. As for the wavelength feature of the TX and RX for the ports on the DWDM Mux Demux, it is similar to the CWDM one, but the channel spacing is denser. What’s more, except for the existing channels in the main single fiber DWDM link, there can be more channels added into the expansion port of the link for carrying larger data signals. In short, although the cost for deploying single fiber DWDM network is so expensive, it is still a good solution that can make full use of the fiber link to transmit more signals at a much longer distance.

Conclusion

Undoubtedly, the single fiber WDM solution is an ideal choice for those who have limited budgets but need for bigger network capacity. As there are two single fiber WDM solutions available, which one to choose just depends on the network need and budget. The single fiber CWDM network would be more economical but can not transmit as much signals as the DWDM one can, while the DWDM is highly recommended for large and long transmission that would cost more.

[katherinewangfs-blog]

10G DWDM Network for Economically Expanding Capacity

It can’t be denied that for most users, the capacity and transmission data rate their 10G networks offer sufficiently meet their needs at present. However, for some users, their 10G networks are capacity-hungry that requires more and more fiber optical cables installed for carrying large data. Considering that the available fiber infrastructure is limited, the method of putting more cables would be infeasible or unsuitable once the infrastructure no longer fulfill the growing requirements. Is there any economical solution to solve this issue, except upgrading the network that would cost a lot? The answer is yes. In order to create new capacity at a relatively low price, WDM technology is come up with that enables virtual fibers to carry more data. Since WDM technology has been a cost effective solution to face the capacity-hungry issue, here will offer the economical DWDM SFP+ transceiver and DWDM Mux Demux solutions for you to build the 10G DWDM network, which enables bigger capacity to meet your network needs.

DWDM SFP+ Transceiver

The DWDM SFP+ transceiver is an enhanced version of DWDM SFP transceiver that can transmit signals at 10Gbps–the max data rate, mostly deployed in the dark fiber project in combination with the DWDM Mux Demux. Like other kinds of SFP+ transceivers, it is also compliant to the SFP+ MSA (multi-source agreement), designed for building 10G Ethernet network. However, the working principle of DWDM SFP+ transceiver is much more complicated than that of common SFP+ transceiver due to the DWDM technology.

Generally, the DWDM SFP+ transceiver has a specific tuned laser offering various wavelengths with pre-defined “colors” which are defined in the DWDM ITU grid. The colors of the wavelengths are named in channels and the wavelengths are around 1550nm. Its channels are commonly from 17 to 61 and the spacing between channels is always about 0.8nm. In fiber optical network, the 100GHz C-Band with 0.8nm DWDM SFP+ transceiver is the most commonly used one, while transceivers with other spectrum bands like 50GHz with 0.4nm spacing DWDM SFP+ transceiver are also popular with users.

According to the transmission distance, the DWDM SFP+ transceiver can be divided into two types. One is the DWDM-SFP10G-40 with an optical power budget of 15dB, and the other is the DWDM-SFP10G-80 with an optical power budget of 23dB. As we know, the bigger the optical power budget is, the longer the transceiver will support the 10G network. Hence, the DWDM-SFP10G-40 can transmit 10G signals at lengths up to 40 km, but the DWDM-SFP10G-80 is able to support the same network with a longer distance, 80 km. What should be paid attention to is that the transmission distance can be also affected by the quality and type of the DWDM Mux Demux, the quality and length of the fiber, and other factors.

DWDM Mux Demux

The DWDM Mux Demux is a commonly used type of fiber optical multiplexer designed for creating virtual fibers to carry larger data, which consists of a multiplexer on one end for combining the optical signals with different wavelengths into an integrated signal and a de-multiplexer on the other end for separating the integrated signal into several ones. During its working process, it carries the integrated optical signals together on a single fiber, which means the capacity is expanded to some extent. In most applications, the electricity is not required in its working process because the DWDM Mux Demux are passive.

Unlike the CWDM Mux Demux with 20nm channel spacing, the DWDM Mux Demux has a denser channel spacing, usually 0.8nm, working from the 1530 to 1570nm band. It is designed for long transmission, which is more expensive than CWDM Mux Demux used for short transmission. Meanwhile, it also commonly used the 100 GHz C-band DWDM technique like the DWDM transceiver. As for its classification, there are basically two types according to line type, dual fiber and single fiber DWDM Mux Demux, and six types according to the number of the channels, 4, 8, 16, 40, 44 and 96 channels DWDM Mux Demux. All these types of DWDM Mux Demux are available at FS.COM with ideal prices. To better understand the DWDM Mux Demux, here offers a figure of a stable 8 channel DWDM Mux Demux for your reference.

Conclusion

Taking the cost issue into consideration, deploying a 10G DWDM network is much more economical than upgrading your network from 10G to 40G/100G which almost requires changing out all the electronics in your network. The 10G DWDM network makes full use of DWDM technology to expand the network capacity, which creates virtual fibers to support more data signals. If your 10G network is also capacity-hungry, you are highly suggested to deploy 10G DWDM network to make new capacity. As for the related components the 10G DWDM network needs like transceiver and Mux Demux, you can easily find them at FS.COM. For instance, FS.COM offers the DWDM SFP+ transceivers compatible with almost every brand, including Cisco, Juniper, Brocade, Huawei, Arista, HP and Dell, which have been tested to assure 100% compatibility.

Originally source: http://www.chinacablesbuy.com/10g-dwdm-network-for-economically-expanding-capacity.html

[qing-chloe-blog]

Solutions to Achieve Long-haul Transmission With DWDM Systems

In order to increase the transmission distance of optical signals, many technologies, like the TDM (time division multiplexing) and WDM (wavelength division multiplexing), have been used. Expect for that, several optical components like single mode fiber optic cables, optical amplifiers and dispersion compensating modules (DCMs) are also put into use to realize the goal. Today, this article intends to illustrate the solutions to achieve longer transmission distances with DWDM technology.

Solutions to Extend Transmission Distances

When it comes to long-haul optical transmissions, DWDM (dense wavelength division multiplexing) is a topic that cannot be ignored. DWDM technology enables different wavelengths to transmit over a single optical fiber. Different wavelengths are combined in a device—Mux/Demux which is short of multiplexer/demultiplexer. The DWDM Mux/Demux provides low insertion loss and low polarization-dependent loss for optical links. Here take a 8CH DWDM Mux/Demux for example to illustrate how to extend distance in long haul transmission.

Solution One

The first solution is suitable for applications that are less than 50km. The picture below shows a unidirectional application with 8CH DWDM Mux/Demux. As we can see, in this links, the DWDM Mux/Demux transmits 1550nm signal over one single mode fiber. The eight different signals from the transmitters are multiplexed into 1550nm signal by the 8CH DWDM Mux. Then they go through the single mode fiber and are separated into the original wavelengths by the DWDM Demux. The use of DWDM Mux/Demux and single mode fiber allows the system to transmit over 50km without optical amplifier or DCM.

Notes: this solution is the basic application of DWDM Mux/Demux in a relative long distance comparing to CWDM technology which suits short distance deployment.

Solution Two

Different from the first solution, if the link distance is longer than 50km, this solution can be taken into account. Optical signal loss will become greater as the links are getting longer, which means an optical amplifier module or dispersion compensator is needed. Therefore, to achieve a satisfying signal quality in long-distance transmission, an EDFA which can boost the weakened optical signals is added in this solution (as shown in the picture below).

Solution Three

This DWDM configuration is similar to the former one, but with the EDFA, the link distance on the single mode fiber is up to 200km. However, sometimes an EDFA is not enough to achieve a quality signal, especially in some long haul systems like CATV system. Because these systems often have a high requirement for the quality of optical signal. Therefore, as we can see in the following picture, except for the DWDM Mux/Demux and EDFA, there is also a DCM.

This solution is a point-to-multipoint long haul system deploying a DCM to extend the transmission distance. From the picture, the EDFA is placed midway between the transmitter and receiver in the transmission path. And in order to ensure the quality of the whole transmission, a DCM module is added in this link to deal with the accumulated chromatic dispersion without dropping and regenerating the wavelengths on the link.

Notes: all the three solutions are unidirectional transmission on single mode fiber cables. If a network requires bidirectional transmission to transfer eight signals, you can use a 16CH DWDM Mux/Demux over single fiber or a 8CH DWDM Mux/Demux over dual fiber.

Summary

WDM technology, especially the DWDM, is the critical step to go into the super-long distance transmission in optical communication. This post mainly introduces three basic solutions to realize long haul transmission with DWDM Mux/Demux. All the components including the DWDM Mux/Demux (both 8 channels and 16 channels), EDFA, DCM and optical modules are available in FS.COM. If you have any needs, please contact us via sales@fs.com.

From:http://www.fiber-optic-components.com/8-channel-dwdm-mux-demux-for-long-haul-transmission.html