Search Results for 'wdm'

[Hamza Ali Abbas KhanParticipant]

Hello,
As far as loops are concerned there are few links i am posting that might help u. Generally The Loop Control allows you to set the number of times the signal propagates in the components that are connected between the Loop Control input and output ports. Use the Loop Control to calculate the system performance based on the number of fibers.
To connect the Loop Control, perform the following procedure.
From the Component Library, select Default > Tools Library.
Drag the Loop Control to the Main layout.
Connect the output port of the WDM Mux 8×1 to the first Loop Control input port.
Connect the first Loop Control output port to the Optical Fiber input port.
Connect the output port of the second EDFA Ideal (connected to the Optical Fiber) to the Loop Control input port.

Here is the complete link

Lesson 3: Optical Systems — WDM Design

why use loop control in circuit

Dispersion Compensation Schemes – A System Perspective

Hope this helps you
Thanks

[Hamza Ali Abbas KhanParticipant]

Hello,
Reflective Semiconductor Optical Amplifiers (RSOAs) offer a cost effective wavelength agnostic transmitter for applications within wavelength division multiplexed passive optical networks (WDM PONs) obviating the need for tuneable or fixed laser sources at customer premises. The RSOA, seeded with a single continuous wave source at the ONU (Optical Network Unit) can be shared among a number of users and can simultaneously amplify and modulate that seed to support a WDM overlay in a wavelength agnostic manner. A summary of the operational performance of RSOAs across several wavelength bands and conclusions on their potential in future PON evolutions is presented here. Please refer to the link.
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5185149&abstractAccess=no&userType=inst
Hope this will help.
Thanks

[Hamza Ali Abbas KhanParticipant]

Hi,
I want to add that similar to Mode Field Diameter(MFD), the effective area of the fundamental mode is a measure of the area over which the energy in the electric field is distributed.
effective area in a single mode optical fiber determines how much energy the core can can carry without causing non-linear type signal losses. This parameter is important for DWDM applications.
Whilst the effective area characteristics are frozen at the time of manufacture and as such are fixed for the life of the fiber, it is a parameter that is influenced by various properties within the fiber that do vary along its length, so it is useful to measure the effective area even within a cable manufacturing environment to ensure the consistency of the product.
Hope it helps.
Thanks

[Hamza Ali Abbas KhanParticipant]

Hi,
Fiber amplifiers used in WDM systems usually make use of control systems as power or gain. Designs Er-doped fiber amplifiers by considering numerical solutions of the rate and the propagation equations under stationary conditions. The model includes amplified spontaneous emission (ASE) as observed in the amplifier Erbium Doped Fiber.
The main difference is related to the amplifier pump scheme selection. You can choose co-propagating, counter-propagating, or bi-directional pump schemes with the option to set wavelength and pump power. Geometrical Er-doped fiber parameters and cross-section curves are required as input files. As output files, you can access gain, output power values, and noise figure determined in the ASE bandwidth set as noise input data.
Enables the design of amplifiers, including EDFAs, that consider pre-defined operational conditions. This means that expected gain, noise figure, and amplifier output power can be previously specified. The amplifier presents the same facilities as a black box model, which enables you to select the operation mode with gain control, power control, or to perform simulations under saturated conditions, as well as define the expected amplifier performance. It is specially suited to perform prompt performance analysis of one or cascaded amplifiers in a long-haul system.

Hope this helps.
Thanks

[Karan AhujaSpectator]

Hi Ranjeet.
as far as DWDM is concerned , Dense Wavelength Division Multiplexing (DWDM) is a technology that allows multiple information streams to be transmitted simultaneously over a single fiber. This provides a cost effective method to increase the capacity of the existing networks without the need to add additional fiber. This application note explains capabilities of the OptiSystem software to explore different design structures (e.g. modulation format, linear and nonlinear impairment compensation) to optimize the performance of these networks for access and long-haul application.
It has few applications:
Long-haul optical networks either in point-to-point or ring topology, Expanding the capacity of an existing optical network and Capacity leasing for network wholesalers.

Hope it helps
Regards

[Hamza Ali Abbas KhanParticipant]

I would also like to add that With the recent advancements in access networks the TDM PON, like Ethernet passive optical network (EPON) and Gigabit Passive optical network (GPON), are now widely used as optical access network solutions to distribute reasonably high bandwidths to the customers through an optical fiber network infrastructure. Researchers are aiming at optical access network concepts known as hybrid WDM/TDM access passive optical networks.
Various techniques and components of the network are designed to achieve high data rate transmission to large bandwidth such as tuneable optical add/drop multiplexer (OADM) , colorless ONU , selfhomodyne and differential coding , a reflective semiconductor optical amplifier (SOA) and Bragg reflectors. The passive optical networks are constituted of a centralized
OLT located in the central office and a number of ONUs located at the users premises to some distance away from the OLT.

I hope this is useful

[Hamza Ali Abbas KhanParticipant]

Hi
i would like to add that there are three types of PON system, namely B-PON, G-PON and GE-PON. the GE-PON system has been developed and implemented it as a cost-effective optical access system with a high throughput. With a PON system, optical fibers and transmission devices are shared by multiple customers in order to provide FTTH services at low cost. This means that even when accommodating several customers at once, each customer can be provided with high-speed data transmission at a maximum data rate of 100 Mbit/s.
Once fibers are deployed in the field, it would be a critical issue how to migrate to WDM-PON because current Time Division Multiplexing (TDM)- based PON solutions cannot exploit the huge bandwidth of the optical fibers and therefore will have difficulties in meeting ever-increasing demands for higher bandwidth by future network applications.

I hope this will be helpful.
Thanks

[Rajguru M. MohanParticipant]

Hi,
Wavelength Division Multiplexed PON
There are many concepts concerning how WDM-PON may
be implemented and several were studied in the context of
NG-PON2. They are Externally seeded WDM-PON,Wavelength re-use WDM-PON , Tunable WDM-PON, Ultra-dense Coherent WDM-PON.
WDM PON uses multiple wavelengths to
provision bandwidth to ONUs, while OFDM PON employs a number of orthogonal
subcarriers to transmit traffic from/to ONUs.With the WDM or OFDM technology,
these PONs are potentially able to provide higher than 40Gb/s data rate and even
Tera bps data rate. due to the high system cost.
WDM PON allows each user being dedicated with one or
more wavelengths, thus allowing each subscriber to access the full bandwidth
accommodated by the wavelengths.

Here are links for WDM-PON as:
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6645106
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4054038
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6360172

Thanks,

[Ranjeet KumarParticipant]

Hi,
I would suggest you to
apply dense wavelength division multiplexing
(DWDM) to the system will be a strong candidate
in order to support all of BS’s for fiiture fiber-optic
access network infrastructure. There have been
several reports on such DWDM radio-on-fiber
systems [I]-[3]. To increase the spectral efficiency
of the system, the concept of optical frequency
interleaving was first proposed by Schaffer et al.
by simultaneous upconversion scheme with an
electro-optic modulator [4]. Recently, a simple
method to increase the spectral efficiency by
optical frequency interleaving was proposed in
which the modulation format could be either
optical double side band (DSB) or optical single
side band (SSB).The transmitted signal (A) is fed to a
high-Finesse Fabry-Perot etalon (FP) through an
optical circulator (OC). Thc free spcctral range of
the FP is adjusted to cqual to the channel spacing.

Thanks,

[Rajguru M. MohanParticipant]

Hi Fayoqa,
i want to discuss the characteristics and disadvantages of different optical amplifiers which will help you to solve your problems.
Advantages & Disadvantages of EDFA
Advantages
Wide spectral band amplification with relative flat gain (>20 dB) – useful for
WDM applications.
Saturation output > 1 mW (10 to 25 dBm).
Gain-time constant long (>100 msec) to overcome patterning effects and intermodulation
distortions ( low noise).
Large dynamic range.
Low noise figure.
Polarization independent.
Suitable for long-haul applications.
This EDFA has high pump power utilization (>50%)
Directly and simultaneously amplify a wide wavelength band (>80nm) in the 1550nm region, with a relatively flat gain
Flatness can be improved by gain-flattening optical filters
Gain in excess of 50 dB
Low noise figure suitable for long haul applications
Disadvantages

Size of EDFA is not small
It can not be integrated with other semiconductor deviecs
Thanks,

[Rajguru M. MohanParticipant]

Hi Naazira,
As SDN is related to optical networking SONET ,
it has wide scope in optisystem.
The OFC which is the largest global conference and exposition for optical communications and networking professionals.
It attracts the following field, which offers key networking and partnering opportunities, and provides insights and inspiration on the major trends and technology advances affecting the industry like: Optical Networking
•
Gigabit Ethernet
•
SDN and Networks
•
Test and Measurement
•
Optical Packets
•
Optical Interconnects/Switches
•
100Gb/s Hardware
•
WDM
•
Switches
•
ROADMs
•
VCSEL
•
Transport
•
Spatial Division Multiplexing
•
Integrated Photonics
•
FTTX,

Thanks,

[Rajguru M. MohanParticipant]

Hi Vikas,
I would suggest you to go for hybrid amplifier (raman and EDFA) for long haul DWDM system.
As soliton is a new topic, as The existence of an optical soliton in
fibers is made by deriving the evolution equation for the complex
light wave envelope (or the slowly varying Fourier
amplitude) by retaining the lowest order of the group dispersion
(variation of the group velocity as a function of the light
wave frequency) and the nonlinearity, which for a glass fiber
is cubic and originates from the Kerr effect.

i also have very less interest in soliton transmission.

[Rajguru M. MohanParticipant]

Hi,
In addition to this i want to share some information about Four Wave Mixing, as Four-wave mixing (FWM)
is a phenomenon that must be avoided in DWDM transmission, but depending on the application it is the basis of important second-generation
optical devices and optical device measurement technology.
It is one of major issues related to DWDM restricting its performance,
but in the transmission of dense wavelength-division multiplexed
(DWDM) signals, FWM is to be avoided, but for certain
applications, it provides an effective technological basis
for fiber-optic devices. FWM also provides the basic technology
for measuring the nonlinearity and chromatic dispersion
of optical fibers.
Four-wave mixing (FWM) is a type of optical Kerr effect, and occurs
when light of two or more different wavelengths is
launched into a fiber. Generally speaking FWM occurs
when light of three different wavelengths is lauched into a
fiber, giving rise to a new wave (know as an idler), the
wavelength of which does not coincide with any of the others.
FWM is a kind of optical parametric oscillation.

Thanks,

[Thomas Freir]

Hello, I am running a number of simulations of both unidirectional and bidirectional 4 channel CWDM systems. While specifying the MUX and DEMUX I noticed that there is no parameter for directivity (also known as near end crosstalk). On further investigation of the optisystem component library I cannot find mention of it for any component where it would be a common parameter (e.g. 3 port optical coupler).
Am I missing something?

[umer ashraf waniParticipant]

FOR WDM one have to analyze dispersion wrt center frequency