Performance Analyses of Dense Wavelength Division Multiplexing in Ring Metropolitan Area Networks With and Without Erbium Doped Fibre Amplifier
This Paper investigates the performance of dense wa v length division multiplexing ring networks implemnted in the metropolitan areas for the purpose of deploy ing higher bit rates. The investigations were carri ed out in the Cband operating region by deploying four channels over a single standard mode fibre with channel spacing of 100GHz at 10Gbps. Transmissions of 108km and 7km with and without Erb ium Doped Fibre Amplifier (EDFA) were achieved with a 10 fixed value of Bit Error Rate (BER). The performanc e was measured through a bit rate analyser using an eye diagram.
A Novel Approach on DWDM based metropolitan ring network
In the past few years, there are many approaches to increase in the bandwidth requirements of modern telecommunication networks. This has been mainly driven by the rise in the degree of popularity of the Internet and increased ever demand of multimedia applications A router or any switch can associate into a dense wavelength division multiplexing (DWDM) by transfer packets directly onto a wavelength without the use of a SONET or SDH TDM. In effect, a TDM can be replaced with an optical DWDM, which can increase bandwidth utilization, facilitate networking, and reduce cost. DWDM can defer or completely expel the need for extra fiber. DWDM state into the metropolitan interoffice (IOF) and access networks, it will rely on the optical add/drop multiplexer (OADM) as its core network element for metro optical networking. DWDM technology indeed now offers bandwidth as currently available systems support up to about 100 wavelengths per fiber; qualify a single fiber to carry a few hundred gigabits per second of information. In this paper we propose to increases the data transfer rate over the optical fiber with different modulation techniques.
Low-Cost Encoding Device for Optical Code Division Multiple Access System
Problem statement: Instead of using Fiber Bragg Grating (FBG) to develop the coded spectrums, which consist of expensive elements, the grating also are highly sensitive to environmental changes and this will contribute to the increment of capital and operational expenditures (CAPEX and OPEX). Approach: This study presented the development of low-cost 16-ports encoding device for Optical Code Division Multiple Access (OCDMA) systems based on Arrayed Waveguide Grating (AWG) devices and optical switches. The encoding device is one of the new technologies that used to transmit the coded data in the optical communication system by using AWG and optical switches. It provided a high security for data transmission due to all data will be transmitted in binary code form. The output signals from AWG were coded with a binary code that given to an optical switch before it signal modulate with the carrier and transmitted to the receiver. The 16-ports encoding device used 16 Double Pole Double Throw (DPDT) toggle switches to control the polarization of voltage source from +5 V to -5 V for 16 optical switches. When +5 V was given, the optical switch will give code '1' and vice versa. Results: We found that the insertion loss, crosstalk, uniformity and Optical Signal-Noise-Ratio (OSNR) for the developed prototype are <12 dB, 9.77 dB, <1.63dB and ≥20 dB. Conclusion: We had successful developed the AWG-based OCDMA encoding device prototype and characterized using linearity testing and continuous signal testing. The developed prototype was expected to be applied in the optical communication system on Passive Optical Networks (PONs).