oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Simulation of full duplex data transmission in ROF system using Optisystem
Sandeep Singh,Neeraj Gupta,Ravi Prakash Shukla,Anamika Sharma
International Journal of Electronics and Computer Science Engineering , 2012,
Abstract: Wireless coverage of the end-user domain; be it outdoors or indoors, is poised to become an essential part of broadband communication networks. In order to offer integrated broadband services (combining voice, data, video, multimedia services, and new value added services), systems will need to offer higher data transmission capacities. The need for increased capacity per unit area leads to higher operating frequencies, smaller radio cells and large number of base stations (BSs), therefore cost-effective BS development is a key success to the market. For this radio over fiber (RoF) technology has been proposed since it provides functionally simple BSs that are connected to a central station (CS) via an optical fiber. A full-duplex data and video signal transmission over single-mode fiber (SMF) based on wavelengthdivision-multiplexing (WDM) and an optical add-drop multiplexing (OADM) technique is proposed and simulated. Four data signals of 1.25 Gb/s /9.1-9.4GHz are transmitted over long-haul single-mode fiber for downlink transmission. For uplink transmission, four data signals, each from a BS, of 1.25 Gb/s/9.6-9.9GHz is used. Good bit error rate (BER) performances were achieved for both down-link and up-link transmissions in our full-duplex RoF transport system.
The characterization of step index single mode silica fiber for long haul signal communication
Kude, Vivek;Khairnar, Rajendra;
Materials Research , 2005, DOI: 10.1590/S1516-14392005000300006
Abstract: the optical properties of single mode fibers, which are drawn from the silica preform made by mcvd technique, have been studied. the properties such as cutoff wavelength, chromatic dispersion, and polarization mode dispersion (pmd) were studied for 2.3 km length of single mode fiber (smf). the cutoff wavelength was measured by fiber optic test procedure (fotp)-80 which was found to be 1179 nm. the chromatic dispersion was measured by fotp-169 at various wavelengths, the zero dispersion being observed at 1503 nm. the pmd was measured by interferometric method, and exhibited the magnitude of 0.07 ps at 1550 nm. the results are discussed to assess the suitability of these fibers for long haul communication systems.
32 x 10 and 64 × 10 Gb/s transmission using hybrid Raman-Erbium doped optical amplifiers  [PDF]
Shveta Singh,Ramandeep Kaur,M.L.Sharma
International Journal of Advanced Computer Sciences and Applications , 2011,
Abstract: We have successfully demonstrated a long-haul transmission of 32 × 10 Gbit/s and 64 × 10 Gbit/s over single-mode fiber of 650 km and 530 km respectively by using RAMAN-EDFA hybrid optical amplifier as inline and preamplifier amplifiers. The measured Q-factors and BER of the 32 and 64 channels after 650 and 530 km respectively (16.99–17 dB) and (10-13) were higher than the standard acceptable value, which offers feasibility of the hybrid amplifiers including EDFA optical amplifiers for the long-haul transmission.
Effect Of Line-Width Variation In Radio Over Fiber System Based On Optical Single Side Band For Short Haul Communication  [PDF]
Abhimanyu
International Journal of Computer Science and Management Studies , 2012,
Abstract: Carrier to Noise Ratio (CNR) has been investigated for radio overfiber systems including the effects of variation in the RF oscillatorlinewidth in this paper. Optical Single sideband signal is studied as ithas tolerance for power degradation due to dispersion effects over alength of fiber. Investigations have been made out for Radiofrequency of 30 GHz, with a continuous wave (CW) laser source of1550 nm. CNR has been evaluated using Power SpectralDensity(PSD) function.CNR is studied varying RF oscillatorlinewidth and RF oscillator linewidth for 2 Km fiber with chromaticdispersion D=17 ps/Km nm.
Adaptive Performance Improvement of Fiber Bragg Grating in Radio over Fiber System  [PDF]
Fabrice Mfuamba Kabonzo, Yunfeng Peng
Journal of Computer and Communications (JCC) , 2016, DOI: 10.4236/jcc.2016.43001
Abstract:

The combination of Radio Frequency and Optical Fiber has resulted high capacity transmission at lower costs components and makes Radio over Fiber as a current trend of large broadband communication. In Fiber optics field, the use of Fiber Bragg Grating (FBG) was been proposed in recent research with different purpose of uses. However, the compensation of dispersion method of Fiber Bragg Grating (FBG) can boost significantly the system performance. This paper investigates the performance capacity improvement of adaptive Radio over Fiber system. The system design was performed using OptiSystem 7.0 software, which 10 Gb/s Non Return to Zero (NRZ) signal was launched into 50 Km Universal Mode Fiber and Fiber Bragg Grating was used as a compensator of dispersion before frequency up conversion. Therefore, the system performances were investigated by comparing the Bit Error Rate (BER) and Q-factors of Positive Intrinsic Negative (PIN) and Ultrafast Avalanche Photodiode (APD) as optical receivers. The Eye diagram analyzer showed acceptable improvement due to use of Fiber Bragg Grating as a compensator of dispersion.

Analysis of transmission characteristics of tilted long period fiber gratings with full vector complex coupled mode theory?
Qi Li,Fengping Yan,Peng Liu,Wanjing Peng,Guolu Yin,Ting Feng
Photonic Sensors , 2012, DOI: 10.1007/s13320-012-0049-4
Abstract: Based on the full vector complex coupled mode theory, a detailed analysis is made on the transmission spectrum characteristics of tilted long period fiber gratings. New transmission peaks are observed, which are located beside the long wavelength side of each transmission peak in the transmission spectrum of normal long period fiber gratings. The emerging transmission peaks are quite sensitive to both the grating tilted angle and the surrounding refractive index, and the corresponding relationship is discussed. Furthermore, a novel sensing characteristic is investigated about the tilted long period fiber gratings, which is related to the transmission resonant wavelength and peak amplitude.
Mode-Dependent Loss and Gain: Statistics and Effect on Mode-Division Multiplexing  [PDF]
Keang-Po Ho,Joseph M. Kahn
Mathematics , 2011, DOI: 10.1364/OE.19.016612
Abstract: In multimode fiber transmission systems, mode-dependent loss and gain (collectively referred to as MDL) pose fundamental performance limitations. In the regime of strong mode coupling, the statistics of MDL (expressed in decibels or log power gain units) can be described by the eigenvalue distribution of zero-trace Gaussian unitary ensemble in the small-MDL region that is expected to be of interest for practical long-haul transmission. Information-theoretic channel capacities of mode-division-multiplexed systems in the presence of MDL are studied, including average and outage capacities, with and without channel state information.
Understanding Standard OFDM Wimax Signal Access in Radio Over Fiber System
Chien-Hung Yeh;Chi-Wai Chow;Chia-Husan Wang;Fu-Yuan Shih;Yu-Fu Wu;Yen-Liang Liu;Sien Chi
PIER C , 2009, DOI: 10.2528/PIERC09081201
Abstract: Radio over Fiber (RoF) system has attracted much industry and research interest to extend the wireless cell coverage and reduce the cost by using the distributed remote antenna units (RAUs). However, the effective transmission fiber length in the RoF systems would be limited due to the time division duplex (TDD) mode used in the practical WiMAX access. Here, we study the transmission limitations and performances of the standard WiMAX signal for RoF systems. The throughputs and packet-losses at different fiber lengths are also investigated and analyzed. Besides, in order to increase the emitting power of the RAUs, a robust TDD switching mechanism is proposed in each RAU for RoF system.
Simulative Analysis of Influence of Modulation Techniques on COFDM based Radio over Fiber Transmission  [cached]
Shikha Mahajan,Naresh Kumar
International Journal of Modern Education and Computer Science , 2012,
Abstract: In this paper, Coded Orthogonal Frequency Division Multiplexing (COFDM) based Radio over Fiber (RoF) system is simulated (for different bit rates) for different modulation techniques to observe impact on system parameter [quality factor (Q)]. Influence of increasing bit rates has been observed for 2 km long linear multimode fiber. To reduce dispersion due to multimode fiber, convolutional encoder (code rate , generator polynomial 1338, 1718) and viterbi hard decision decoding algorithm are chosen for simulative model of COFDM based RoF system. Transmission of 32 sub-carriers with externally modulated continuous wave laser source gave satisfied results for Q values.
Fiber Bragg Grating And Phase Conjugator As Dispersion Compensator
Smita S. Dabhade,Savita Bhosale
International Journal of Advanced Electrical and Electronics Engineering , 2012,
Abstract: Among the promising advancements towards cost-effective long-haul transmission are the use of Fiber Bragg Gratings (FBGs) and Optical Phase Conjugator (OPC) as the dispersion compensating module (DCM). In this paper we discuss the the performance of FBG and OPC by comparing the results of the receivers. A 10 Gb/s Non Return To Zero (NRZ) signal is launched onto a 100 km long standard single mode fiber. Comparison of eye diagrams & Bit Error Rate (BER) and quality factor show a marked improvement in the link performance due to compensation of dispersion
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.