Search Results for 'wdm'

[Ahmad AtiehModerator]

Dear Aseel,
The issue could be related to the setting of the operating wavelength range of the Dual Port WDM Analyzer.
Please set the proper range and make the measurements.
Regards,
Ahmad

[Aseel Rwaidi]

Hello,
I simulated an optical system over a UOWC, where I added AWGN with a sweep of input power levels to the channel using a white light source component. I aim to extract the SNR using a Dual WDM Analyzer component to plot it versus the BER. The encountered problem is that when I connected the input of the Dual WDM Analyzer to the output of the white light source and the output of the Dual WDM Analyzer to the input of the UOWC channel. However, the Dual WDM Analyzer gives no results. What could be the problem and how can I resolve it to successfully extract and plot the SNR?

[R D SOUMITRAParticipant]

I am simulating a WDM system with 16 channels with frequencies from 193.1 THz to 194.6 THz with 100 GHz frequency spacing. The multiplexed signal is to combined with a pump signal for optical phase conjugation. What should be the frequency of the laser used for this pump signal?

[R D SOUMITRA]

On what basis do we select the frequency of the pump lasee used in the optical phase conjugation module for chromatic dispersion compensation in WDM systems?

[Ahmad AtiehModerator]

Dear Lared dar,
You may use the tool box in the OSA visualizer. You need to right click in the display window then get access to the marker and info tools. Another option is to use the WDM Analyzer to get details on each existing wavelength/frequency in your project, then calculate the ratios. You may add your own VB scrip in the component to calculate the ratio. You could access the VB scripting window of the analyzer by right click on it then choose Component script.
Regards,
Ahmad

[Arajit Saha]

BER ANALYZER:
When I use a BER analyzer to determine the BER of a Dual Polarization CO-OFDM system using an OS12 OFDM Modulator and an OS12 OFDM Demodulator, It always shows 0 or 1! In between those two values, I didn’t get any value like (10e^-x). But the EYE diagram is clear.

I want to mention that I changed the BER Analyzer Properties according to the sample file. Where I changed “Ignore END bits” by the following equation “Int(Sequence length/(104+14)) * 14 + Sequence length – Int(Sequence length/(104+14)) * (104+14)”, Here, Number of Subcarriers=104; Number of Prefix Points= 14.

BER TEST SET:
Again, for the BER Test Set for Direct Detection OFDM 4QAM sample file, when I change the bit rate (According to Sequence length) or optical length and run that simulation, it always shows 0, but when I go to the Result properties, it shows unacceptable result! When I increase the bit rate and, therefore, the Sequence length goes beyond the limit, It shows that the simulation is cancelled. But that time, it also shows BER 0.

Can anyone help me find out about this issue? I want to design a DWDM-based Dual Polarized CO-OFDM System.

[Krishna Sarma]

I am designing an optical link using a hybrid EDFA-TDFA amplifier. Suppose my amplifier works well at an input power say -20 dBm. If I apply -20 dBm input power in the fiber link then after modulation and passing through a fiber of length say 50 km, input power to the amplifier will become different. Do I need to provide input power to the amplifier separately?

Again the amplifier provides a better gain (35 dB) at a specific wavelength but while connecting the amplifier in an optical link the amplifier shows a minimum BER of 1. However, although the gain is low at different wavelengths, BER performance is good.
Can anyone help me to resolve the issues?

[Vamsi mohan]

Hi

How to connect PBS to WDM De-Mux?
I noticed one article which shows this
connection. As PBS has two outputs
and De-Mux has only one input,
how to make this connection?
Please see the image and reference paper.
Ref:An Effective Design of Hybrid Spectrum Slicing WDM–PDM
in FSO Communication System Under Different Weather
Conditions
Ekta Vasani · Vrushank Shah
Wireless Personal Communications (2023) 130:777–800
https://doi.org/10.1007/s11277-023-10309-3

regards
Vamsy

[Ahmad AtiehModerator]

Dear Krishna,
please refer to the datasheet of the Dual Port WDM Analyzer for details on the equations used to calculate the NF. You could access the datasheet from the Help button of the component properties that you could access by right click on the visualizer and select Component Properties…
Regards,
Ahmad

[Krishna Sarma]

I have designed a hybrid optical amplifier connecting EDFA and TDFA in parallel. At the output, I have connected a power combiner to get the amplifier’s overall gain. A dual-port WDM analyzer is used to see the gain and noise figures at specific wavelengths. Can anyone help me with the formula for the gain and noise figure used by the WDM analyzer for this configuration?

[Krishna SarmaParticipant]

I have designed a hybrid optical amplifier connecting EDFA and TDFA in parallel. At the output, I have connected a power combiner to get the amplifier’s overall gain. A dual-port WDM analyzer is used to see the gain and noise figures at specific wavelengths. Can anyone help me with the formula for the gain and noise figure used by the WDM analyzer for this configuration?

[Sun Mingming]

Recently, I simulated the system of single channel and dual channel of DWDM system by optisystem. Why is the constellation diagram obtained by single channel very different from that obtained by dual channel? I want to find out whether there is any problem in my setting.I have attached the results of my constellation diagram and the block diagram of the construction of the DWDM system. I have used DSP for dispersion compensation and nonlinear compensation. But the constellation chart is still not ideal, please help me check it, thank you.

[Jarrod HoneycuttMember]

Sir I am getting this values from WDM analyzer at a particular wavelength in EDFA

Wavelength (1492 nm) Gain (15.4596 dB) Noise Figure (5.6398562 dB) Input Signal (-50.002673 dBm) Input Signal (9.99E-09 W) Input Noise (-100 dBm) Input Noise (0 W) Input SNR (49.997327 dB) Input Noise 0.1nm(-100 dBm) Input Noise 0.1nm(0 W) Input OSNR (49.997327 dB) Output Signal (-34.543073 dBm) Output Signal (3.51E-07 W) Output Noise (-36.722209 dBm) Output Noise (2.13E-07 W) Output SNR (2.1791354 dB) Output Noise 0.1nm(-36.722209 dBm) Output Noise 0.1nm(2.13E-07 W) Output OSNR (2.1791354 dB)

So, according to the values NF should be OSNR(input)-OSNR(output)= 49.997327 dB – 2.1791354 dB = 47.8182 dB. But noise figure shown by WDM analyzer is 5.63 dB.
I want to know which formula is used here to calculate the noise figure..

[Ahmad AtiehModerator]

Dear Krishna,
You could find the equations for NF calculation in the datasheet of the Dual port WDM Analyzer as shown in the attached file.
regards,
Ahmad

[Naaman Cherif]

Hello everyone, I apologize for the simplicity of these questions. I would like to understand the significance of the color grades (yellow,orange,red pink, blue etc.) displayed in the BER analyzer. For example, in the attached picture, I have the results of two WDM systems, both simulated at a power level of -15 dBm with RZ modulation. However, one system includes Radio over Fiber (RoF) while the other does not. I noticed that the color grades are more prominent in the RoF system. I would appreciate any clarification on this matter. Thank you!