Crosstalk suppression techniques for multi-channel regeneration based on fiber optic parametic amplifier

Optical transmission system is the best choice to transmit high capacity information over long distances. The progressive development in optical transmission technologies allows the growth of transmission speed and capacity.2R or 3R regeneration can refine the degraded signal and improve transmission performance. 2R stands for reamplifying and reshaping the signal, and 3R adds retiming of the signal. Conventionally, electrical repeaters are used for the regenerations. In this regeneration system, the signal is converted from optical to electrical, regenerated electrically and finally converted back to an optical. Besides the electrical repeater, all optical regenerator is an alternative to regenerate optical signal without the need of optical electrical optical signal conversions. All optical signal regeneration has been recognized as a potential enabler of future transparent long haul high bit rate systems. All optical regeneration is easily applicable to various modulations formats signals and can work ultrafast. Since fiber based all optical regeneration was introduced two decades ago, many excellent techniques to regenerate signals have been proposed was introduced in order to reduce nonlinear effect within the channel, two techniques approaches being polarization interleaving and polarization multiplexing. The purpose of the signal regeneration is therefore to remove these distortions and to restore the characteristics of the optical signal to a suitable level so that a high overall transmission quality is maintained. As a result, the improvement of Q factor of each regenerated channel can be more improved for each techniques. In this result, a WDM system with polarization based system is analyzed in order to mitigate the nonlinear effects within the fiber channel. Hence, the performance can be further improved by using concept of polarization modulation in the transmitter section WDM system

SAC-OCDMA over hybrid FTTx free space optical communication networks

This paper presents an investigation of Spectral Amplitude Coding Optical Code Division Multiple Access (SAC-OCDMA) over hybrid Fiber-to-the-x (FTTx) Free Space Optical (FSO) link under different weather conditions. FTTx and FSO are the last mile technologies that complement each other in delivering secure and high speed communication to customers' residence or office. SAC-OCDMA is one of the potential multiplexing techniques that has become a research area of interest in optical communications and considered a promising technique for FTTx access networks. It is based on Khazani-Syed (KS) code with Spectral Direct Decoding (SDD) technique. All the components involved in the network were specified according to the available market product in order to simulate the actual environment as close as possible. The result shows that for bit error rate (BER) of 10-9, the network is able to perform with 20 km Single Mode Fiber (SMF) spanning from the central office (CO) and 1.48 km FSO range with transmission rate of 1.25 Gb/s during heavy rain

Development of a dc-ac power conditioner for wind generator by using neural network

This project present of development single phase DC-AC converter for wind generator application. The mathematical model of the wind generator and Artificial Neural Network control for DC-AC converter is derived. The controller is designed to stabilize the output voltage of DC-AC converter. To verify the effectiveness of the proposal controller, both simulation and experimental are developed. The simulation and experimental result show that the amplitude of output voltage of the DC-AC converter can be controlled

High-Speed Communications Over Polymer Optical Fibers for In-Building Cabling and Home Networking

This paper focuses on high-speed cabling using polymer optical fibers (POF) in home networking. In particular, we report about the results obtained in the POF-ALL European Project, which is relevant to the Sixth Framework Program, and after two years of the European Project POF-PLUS, which is relevant to the Seventh Framework Program, focusing on their research activities about the use of poly-metyl-metha-acrilate step-index optical fibers for home applications. In particular, for that which concerns POF-ALL, we will describe eight-level pulse amplitude modulation (8-PAM) and orthogonal frequency-division multiplexing (OFDM) approaches for 100-Mb/s transmission over a target distance of 300 m, while for that which concerns POF-PLUS, we will describe a fully digital and a mixed analog-digital solution, both based on intensity modulation direct detection, for transmitting 1 Gb/s over a target distance of 50 m. The ultimate experimental results from the POF-ALL project will be given, while for POF-PLUS, which is still ongoing, we will only show our most recent preliminary results