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1000BASE-X Media Components

The following set of media components are used to build a 1000BASE-X fiber optic segment:

1. Fiber optic cable

2. Fiber optic connectors

Gigabit Ethernet fiber optic segments use pulses of laser light instead of electrical currents to send Ethernet signals. This approach has several advantages. For one thing, a fiber optic link segment can carry Gigabit Ethernet signals for considerably longer distances than twisted-pair media can. The standard specifies that a full-duplex 1000BASE-LX segment must be able to reach as far as 5,000 meters (16,404 feet, or a little over 3 miles). However, most vendors sell “long haul” versions of 1000BASE-LX equipment that are designed to reach as far as 10 km (6.2 miles) on single-mode fiber. Vendors have also developed “extended reach” versions of 1000BASE-LX single-mode interfaces that can send signals over distances of 70-100 kilometers or more.

In large, multibuilding campuses, the fiber distances can add up fast, as the fiber cables may not be able to take the most direct route between buildings on the campus and a central switching location. Therefore, these long-reach transceivers can be quite useful. The LX interfaces are essential when it comes to building metropolitan area network(MAN) links, in which Gigabit Ethernet is used to provide network services between sites on a city-wide basis.

Fiber optic cable

Both 1000BASE-SX and 1000BASE-LX fiber optic media segments require two strands of cable: one for transmitting and one for receiving data. The required signal crossover, in which the transmitting and one for reciving data. The required signal crossover, in which the transmit signal (TX) at one end is connected to the receive signal (RX) at the ther end, is performed in the fiber optic link. (Related products in: 10GBASE-LR XFP)

Maximum segment lengths for 1000BASE-SX and 1000BASE-LX are dependent on a number of factors. Fiber optic segment lengths in the Gigabit Ethernet system will vary depending on the cable type and wavelength used.

Fiber optic connectors

The original standard recommended the use of duplex SC fiber optic connectors for both 1000BASE-SX and 1000BASE-LX fiber optic media segments. Figure 1 shows a duplex SC connector. Although the standard can recommend a connector, vendors can use other fiber optic connectors as long as they are not forbidden in the standard. For examle, when the 1000BASE-X media systems first became available, vendors used the compact MT-RJ connector on 1000BASE-SX ports.

21   Figure 1, Duplex SC connector
Figure 2 shows the MT-RJ connector, which provided both fiber connections in a space the size of an RJ45 connector. Because the MT-RJ connector takes up about half the space required by the SC connectors, this allowed vendors to provide more 1000BASE-SX ports on swithch.

22 Figure 2, MT-RJ connector

1000BASE-X transceivers

Some vendors used the Gigabit Interface Converter (GBIC), which was an earlier form of transceiver module that allowed the customer to support either the 1000BASE-SX or 1000BASE-LX media types on a single port. The GBIC is a small, hot-swappable module that provides the media system signaling components for a Gigabit Ethernet port.

More recently, vendors have developed a small form-factor pluggable (SFP) transceiver, which can be purchased to support several different kinds of Ethernet fiber optic media systems.

The SFP Transceiver is a small module the plugs into a seitch port and uses a small fiber optic connector called the LC connector. Figure 3 shows the smaller LC fiber optic plug, which is used for connections to SFP fiber optic transceivers.

23Figure 3, Duplex LC fiber optic plug

Four Families OF 10 Gigabit Ethernet

The IEEE 10 Gb/s standard was first specified in the 802.3ae supplement, which was adopted in 2002. This supplement defined the basic 10 Gigabit system and a set of fiber optic media standards. Subsequent 10 Gb/s supplements have added copper media types, including a short-range copper connection based on twinaxial cable and a twisted-pair media system capable of reaching 300 m.

There are four sets of physical layer(PHY) specification, also called”families”in the standard. which are grouped by their use of the same signal encoding techniques and other elements.

10GBASE-R
Based on 64B/66B signal encoding, this includes the following optical fiber media
systems: 10GBASE-SR, 10GBASE-LR, 10GBASE-ER, and 10GBASE-LRM.

10GBASE-X
Based on 8B/10B signal encoding, including both fiber optic (10GBASE-LX4) and
copper (10GBASE-CX4) media systems.

10GBASE-T
Based on 64B/65B encoding, supporting transmission over twisted-pair cabling.

10GBASE-W
Based on 64B/66B encoding that is encapsulated and transmitted over an OC-192
SONET optical fiber system. This includes the 10GBASE-SW, 10GBASE-LW, and
10GBASE-EW media specifications.

10 Gigabit Ethernet LAN PHYs include five media systems:

10GBASE-SR
10GBASE-LX4
10GBASE-LR
10GBASE-LRM
10GBASE-ER

Each of the LAN PHYs was specified to provide a media system for a specific set of uses. The short-reach systems are intended for connections between switches in a building or a data center, and from switch ports to server interfaces. The long-reach systems, intended for backbone links on campus and enterprise networks, use more expensive. Single-mode laser-based optics to drive 10 Gigabit signals over longer distances, with
ranges from 10 km for the LR system up to 30–40 km for the ER.

The most used fiber Media Components in 10 Gigabit Ethernet:

Multimode fiber optic cable for short-reach applications.
Single-mode fiber optic cables for long-reach applications.
Mode conditioning patch cable for FDDI grade multimode fiber and OM1 or OM2 cables, up to 220m.
Transceiver: The most popular current form is the SFP+ Module.

Fiber-optic-tutorial.com will offer more information about Gigabit Ethernet. You can also buy fiber media components from Fiberstroe.

Learning CWDM Knowledge Follow Me

With the need for greater capactiy of optical communication systems, wavelength divison multiplexing (WDM) technology was developed.
WDM basically puts multiple signals on a single fiber, each one represented by a different wavelength. While early systems utilized two or three wavelengths with relatively wide separation, we would today characterize those as wide wavelength division multiplexing(WWDM) systems, and primarily they employed dual window(Fused Biconic Taper) FBT couplers. These devices typically operated in the range of 810/870/1310nm or 1310/1550nm, with the light sources such as Fabry Perot (FP) lasers or light emitting diodes(LEDs) operating at those wavelengths. Those early systems eventually evolved in what we today know as coarse wavelength divison multiplexing(CWDM) and dense wavelength division multiplexing(DWDM) system. While DWDM is the technology of chocie for long-haul or ultra long-haul(ULH) applications across the network back bones, in metro applications CWDM rapidly filled the gap between DWDM and WWDM systems, yet less expensive and complex than DWDM. Today, CWDM is becoming more widely accepted as an important transport architecture, where up to 18 wavelengths are available for transmitting information over a fiber link in metro or access network.

After i readed some professinal books, i know the agreed technial standards, in many industries, benefi both producers and cosumers by stimulating the uptake of a new technology, reducing costs, and increasing the overall market size of a new technology. CWDM standards have allowed the manufacturers of CWDM lasers and optical filters to commit to mass production of a small range of standardized components that they know will be used by all of telecommunication systems equipment who incorporate standardized components into their designs can reduce their design effort and materials costs.

I will to learn the CWDM standards seriously. In next artcial, i will introduce the stansdards fo you soon.

DWDM System Amplifiers

DWDM EDFA is key component in DWDM network. It uses an optical supervisory channel power adjustment and extends the power link budget for long distance DWDM communication systems.

There are three main types of optical amplifiers: fiber amplifiers (EDFAS), semiconductor optical amplifiers(SOAs), and Raman amplifiers. Fiber amplifiers use rare earth elements usually erbium, but also oraseodymium, tellurite, neodymium, and others as dopant that are pumped with a laser of either 980 to 1480nm. The most commom used for WDM network are the EDFAs.

Types of EDFAs used for DWDM

1 Erbium-doped fiber amplifiers-EDFA. They are low nosie figure approximately 5dB and wide amplitication bandwidth. The EDFA is pumped at 980nm 0r 1480 nm.
2 Erbium-doped fluoride fiber amplifiers(EDFFA) provide for flatter gain spectrum without any gain flattening that introduces loss. They can absorb more erbium than silica producing flatter
band across the erbium passband, allowing the 1530 nm to 1542 region to be used for DWDM. SNR remains the same, or nearly the same for each channel. Howerver, fluoride EDFAs have higher noise from being pumped at 1480nm. DWDM channels must have flat gain through means of an amplifier to properly function. They have proved durable with wavelength stability better than 0.02nm per year.

In DWDM systems amplifiers are an enabling component. For 32 channel DWDM systems optical amplifiers will need to provide at least 25nm of usable bandwidth. 80Gbt/s with 10 Gbt/s channels need 8 wavelengths; 2.5 Gbt/s channels need 32 wavelengths. These must have high outout power and low noise and high signal to noise ratio(SNR). Network spans now at 360km are expected to extend to 600 km then to 2000 km with use of EDFAs. With optical amplifiers the optical signal does not have to be converted and is amplified optically in passing through the amplifier. Optcial fiber amplifiers generate stronger signals than regenerators and transmission can be for extended distances. This takes the place of the SONET regenerator.

PS: 600 km span with DWDM only using 4 optical amplifiers over on fiber pair

dwdm edfa

There are three types if optical amplifiers used in DWDM system. These are:
1 Post amplifier are placed immediately after transmitter to increase optical power to the receiver.
2 In-line amplifiers boost the power level after transmission through a length of fiber permitting the signal to pass through another fiber segment. They are used to compensate for signal attenuation in long segments of fiber. 
3 Pre-amplifiers boost the power of a signal just prior to the receiver.

FiberStore can provide DWDM EDFA amplifiers in different channel from 40~80 channels. These amplifiers offer high optical gain, low noise figure and high saturation optical power which are fully integrated with various kinds of DWDM system.

DWDM EDFA 40 channel BA Module Optical Amplifier

See the video introduction about this products:

This product is spectrum flat EDFA for DWDM system. The stability Pump laser and unique ATC (automatic temperature control) and APC (automatic power control) circuit are employed in it as the key component to ensure the high stability and reliability of output power.The unique optical circuit design ensures the excellent optical character. The high stability and high precision MPU system are employed to ensure the control adjustment and display are intelligent and easy. Professional design GFF (gain flattening filter) with excellent optical path design make flatness and noise reach the best optimization. It can provide 40~80 channels, and above 35nm flatness.

The optical circuit is designed especially for digital optical fiber communication system including
(1) lower noise figure;
(2)high output booster and high sensitivity Pre-Amplifier improve the system loss budget;
(3)Broad input power range and output power adjustable make it use easily.
The design of dual Power Mixed and hot swap make it has longer MTBF. Also, the power system can be backup.Employ the intelligent temperature control system,the fan is on when the module temperature over 45℃, meanwhile it will stop as the temperature is under 40℃, which makes sure the thermal stability and fan’s long life-time, meanwhile, the professional air flow design can also ensure the best temperature stability.Intelligent network management system. Perfectly network interface: Ethernet, RS-485 and RS-232 network interface,and the open mib ensure the connectivity with all other network management system.

Applications
Pre-Amplifier Online Amplifier
Booster
DWDM Optical System

Features
1.Low Noise Figure:Typical 4.5dB High Flatness: Typical 1dB
2.Cover Whole C-Band: Carrie 40 or 80 chs
3.Redundancy hot swap power module: 110/220VAC and 48VDC can plug Mix
4.Perfect Network Interface:Ethernet, RS-485 and RS-232 port
5.Support Telnet and SNMP network management
6.Gain can be adjustable by network and manual
7.High Precise AGC and ATC Circuit
8.High saturation output power
9.Flexible Mechanics and Circuit structure (Module, 1U rack and Gain Block)
10.OEM is available Compatible with Telecordia GR-1312-CORE

DWDMEDFAFS

what is ODC Connector?

ODC connectors are designed for the fiber to antenna(FTTA) applications,ODC fiber optic connector can withstand harsh environmental conditions when being used in outdoor applications. They are used for data and telecommunications in mobile radio, process, utility and traffic automation.

FiberStore provides all types of outdoor fiber connectors. These connectors meet the highest quality and robustness standards, and they offer reliability and flexibility for outdoor applications.
The odc connectors,together with the support optical cable,are becoming the standard interface specified in 3G,4G and WiMax Base Station remote radios and Fiber-to-the-Antenna applications.

The ODC cable assembly is based on the N Type RF Coax connector. ODC  to LC  fiber optic cables are instock.

odc to lc cable

The product,however,is not limited to the above applications, It is also in the oil, wind power, rail transport and heavy machinery of digital information transmission and other areas play a strong role.

The ODC cable assemblies have passed tests like salt mist,vibration and shock and meet protection class IP68. They are well suited for industrial and Aerospace and Defense applications.

odc1

Specifications

Technology Full ceramic ferrule and sleeve
Housing material Nickel plated brass
Mechanical performance ODC plug ≤1000 N tensile load≤30 N static side load
ODC socket ≤30 N tensile load
Installation torque force min.1Nm max.2Nm
Operating temperature IEC 61300 – 2 – 22 -40℃ up to +85℃
Mating durability 1000 cycle
Ingress protection(mate) IEC60529 Ip 68
Salt mist IEC61300-2-26 30 days passed
Vibration IEC61300-2-1 Pass 10-500Hz/10g
Shock IEC61300-2-9 Pass 100g

Related Article: MPO/MTP Connector – Multi-fiber Connector for High Port Density