Wavelength Division Multiplexing: Not Just for Long Distance Anymore

In this paper, we proposed and experimentally demonstrated an opto-mechatronics system to detect the micro-deformation of tracks caused by running trains. The fiber Bragg grating (FBG) array acting as sensing elements has a low peak reflectivity of around −40 dB. The center wavelengths were designed to alternate between 1551 nm and 1553 nm at 25 °C. Based on dual-wavelength, wavelength-division multiplexing (WDM)/time-division multiplexing (TDM) hybrid networking, we adopted optical time-domain reflectometry (OTDR) technology and a wavelength-scanning interrogation method to achieve FBG array signal demodulation. The field experimental results showed that the average wavelength shift of the FBG array caused by the passage of the lightest rail vehicle was −225 pm. Characteristics of the train-track system, such as track occupancy, train length, number of wheels, train speed, direction, and loading can be accurately obtained in real time. This opto-mechatronics system can meet the requirements of 600 mm spatial resolution, long distance, and large capacity for monitoring the train-track system. This method exhibits great potential for applications in large-scale train-track monitoring, which is meaningful for the safe operation of rail transport.

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UltraHigh Bit-Rate Hybrid DWDM Optical System Design Using DP-QPSK Modulation

Journal of Optical Communications ◽

10.1515/joc-2018-0199 ◽

2018 ◽

Vol 0 (0) ◽

Author(s):

Subhrajit Pradhan ◽

Bijayananda Patnaik ◽

Rashmita Kumari Panigrahy

Keyword(s):

Wavelength Division Multiplexing ◽

Long Distance ◽

Eye Diagram ◽

Wavelength Division ◽

Space Optics ◽

Optical Time Domain Reflectometer ◽

Link Distance ◽

Last Mile ◽

Shift Keying ◽

Optical Time

AbstractIn this work, an optical hybrid communication system is proposed. It is a combination of diffused link (DL) configuration of free space optics (FSO) setup and fiber optic setup. It is a 16-channel dense wavelength division multiplexing (DWDM) system, with 400 Gbps/channel data rate. It uses dual polarization-quadrature phase shift keying (DP-QPSK) modulation technique for all the setups. Bit error rate (BER), eye diagram, quality actor (Q-factor), optical time domain reflectometer (OTDR), optical spectrum analyzer (OSA) signals are considered as performance parameters of the proposed system. It is found that the link distance is 340 m for DL setup and 1,000 km for fiber setup. The system will be very much useful for solving first mile, last mile problem with long distance optical communication applications in 5 G era.

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Investigation the Effect of Channel Spacing for Long Distance Communication

CGC International Journal of Contemporary Technology and Research ◽

10.46860/cgcijctr.2019.12.20.45 ◽

2019 ◽

Vol 2 (1) ◽

pp. 45-47

Author(s):

Mamta Janagal ◽

Gurpreet Kaur ◽

Varinder Mandley ◽

Tanvi Sood

Keyword(s):

Wavelength Division Multiplexing ◽

Optical Gain ◽

Input Power ◽

Long Distance ◽

Channel Spacing ◽

Wavelength Division ◽

Received Power ◽

Signal Input ◽

Distance Communication ◽

The Impact

In this paper, the impact of different channel spacing on proposed system setup is investigated for long distance communication. This wavelength division multiplexing (WDM), dense wavelength division multiplexing (DWDM) and ultradense wavelength division multiplexing (UDWDM) is evaluated by considering the signal quality factor, bit error rate, optical gain, and received power for different signal input power and for distance. It is observed that at -5 dBm of signal input power the system covers 130 km with acceptable BER (10-8) and Q-factor (14dB).

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Wavelength division multiplexing with solitons in ultra-long distance transmission using lumped amplifiers

Journal of Lightwave Technology ◽

10.1109/50.70013 ◽

1991 ◽

Vol 9 (3) ◽

pp. 362-367 ◽

Cited By ~ 217

Author(s):

L.F. Mollenauer ◽

S.G. Evangelides ◽

J.P. Gordon

Keyword(s):

Wavelength Division Multiplexing ◽

Long Distance ◽

Wavelength Division ◽

Long Distance Transmission

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Dense Wavelength Division Multiplexing using Dispersion Fibre with Erbium Doped Fiber Amplifier

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.j9922.0981119 ◽

2019 ◽

Vol 8 (11) ◽

pp. 45-48 ◽

Cited By ~ 1

Keyword(s):

Wavelength Division Multiplexing ◽

Signal Transmission ◽

Single Mode ◽

Optical Signal ◽

Dense Wavelength Division Multiplexing ◽

Long Distance ◽

Erbium Doped Fiber Amplifier ◽

Single Beam ◽

Wavelength Division ◽

Erbium Doped

Dense wavelength division multiplexing is used in various broadband communications. It combines information from distinct sources on an optical fiber, each signal being transmitted simultaneously on its own distinct light wavelength. Radio over fibre is a hybrid system that has both fibre optic link and free space radio path. This paper aims to evaluate the performance of the system using Erbium Doped Fibre Amplifier, Single Mode Fibre and Dispersion compensating Fibre. Single beam of light is passed by the SMF and is used for long distance signal transmission. DCF is used to reduce the dispersion in the optical signal. EDFA reduces the degradation of the signal by cancelling the effect of attenuation. It is an optical repeater used to raise the intensity of the optical signal. Mach – Zehnder modulator is used for the modulation. The simulation is carried out by using optisystem software version 15.0. Various parameters like Q-factor, BER pattern, threshold, minimum BER are compared and estimated.

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Modeling and Performance Enhancement of Hybrid Fiber Network-PON/DPPM-DWDM-FSO Communications under Atmospheric Turbulence Conditions

10.21203/rs.3.rs-460066/v1 ◽

2021 ◽

Author(s):

Ebrahim E. Elsayed

Keyword(s):

Optical Networks ◽

Wavelength Division Multiplexing ◽

High Speed ◽

Access Network ◽

High Signal ◽

Hybrid Fiber ◽

Long Distance ◽

Wavelength Division ◽

Digital Pulse ◽

Clear Atmosphere

Abstract A Wavelength Division Multiplexing (WDM) access network using high-speed free-space optical (FSO) communication based on the passive optical networks (PONs) for the distribution link is proposed. In such network architecture, the FSO link can extend the system to areas where an optical fiber link is not feasible, and or provide limited mobility for indoor coverage. The performance of Hybrid Fiber/FSO (HFFSO) network based on digital pulse position modulation (DPPM), for both the indoor and outdoor environments of the optical access network, are compared with the performance of such a network that is based on conventional On-Off Keying Non-Return-to-Zero (OOK-NRZ) modulation using results obtained through computational and analytical modeling. The WDM channels suffer from inter-channel crosstalk, while the HFFSO communication performance in a clear atmosphere is limited by atmospherically induced scintillation. The impairments, plus the amplified spontaneous emission noise from optical amplification, combining in a potentially problematic way, particularly in the upstream direction, which is investigated here. The results obtained indicate that in a clear atmosphere with a sufficiently high signal to crosstalk ratio the proposed system can achieve a human-safe and high-capacity access network. Dense Wavelength Division Multiplexing (DWDM) has dramatically increased the capacity of optical transmission systems. Its inherent advantages have made it the current favorite multiplexing technology for an optical network, also used on fiber optic backbones and long-distance transmission. The crosstalk due to inter-band crosstalk for Ultra-Dense WDM systems causes higher noise and degrades the network performance and analyzed the performance of DWDM-PON link that is corrupted crosstalk for Optical Cross-Connect (OXC). Then the analysis of BER with crosstalk was done. Using the equation for crosstalk number of channels was plotted using Matlab. An analysis is carried out to find the amount of crosstalk considering a WDM-FSO over OOK-NRZ and DPPM based OXC. The bit error rate performance degradation due to crosstalk is evaluated for the OXC parameter and number of wavelength per fiber.

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Multi Soliton Generation for Enhance Optical Communication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.83.136 ◽

2011 ◽

Vol 83 ◽

pp. 136-140 ◽

Cited By ~ 17

Author(s):

Abdolkarim Afroozeh ◽

Iraj Sadegh Amiri ◽

Muhammad Arif Jalil ◽

Mojgan Kouhnavard ◽

Jalil Ali ◽

...

Keyword(s):

Wavelength Division Multiplexing ◽

Ring Resonators ◽

Long Distance ◽

Wavelength Division ◽

Large Bandwidth ◽

Soliton Pulse ◽

Free Spectrum ◽

Distance Communication ◽

Temporal Modes ◽

Soliton Generation

We propose a new optical system that can be used to form the multi-soliton pulses within the micro-ring resonators. The system consists of two micro-ring resonators and an add/drop multiplexer that can be integrated into a single system. The large bandwidth signal is generated by using a soliton pulse propagating in a Kerr-type nonlinear medium. The tuned soliton pulses in either spatial or temporal modes are obtained by using the add/drop multiplexer. Results show the generation of multi-soliton pulses within the micro-ring resonator can be achieved for long distance communication. This results in an increase in the number of channels and spaces with a large free spectrum range (FSR) of 650 pm for dense wavelength division multiplexing (DWDM).

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