Radio-over-Fibersystem Capacity Improvements by Using Wavelength Division Multiplexing and Subcarrier Multiplexing Techniques

Abstract

Radio-over-Fiber (RoF) system refers to the radio signals which are modulated with optical signal and transmitted over optical fiber link from Central Office (CO) to the Remote Nodes (RN s). In this paper, RoF system with Wavelength Division Multiplexing (WDM) and Subcarrier Multiplexing (SCM) techniques, has been designed and simulated with different modulation schemes (such as: 4-QAM-OFDM, 16-QAM-OFDM and 64-QAM-OFDM schemes) to increase the capacity of the system by 20×8 Gbps data rate. The simulation results show that the SCM-WDM-RoF with 16-QAM-OFDM scheme gives better performance with symbol error rate (SER) equal to 10-9 , and reduces the power consumption compared with SCM-WDM-RoF system with other modulation schemes which have been used in this work. The software package "Optisystem version 12" has been used to simulate this system. ‫الموجي‬ ‫الطول‬ ‫تقسيم‬ ‫مضاعفة‬ ‫تقنيات‬ ‫باستخدام‬ ‫االلياف‬ ‫عبر‬ ‫الراديو‬ ‫نظام‬ ‫قدرة‬ ‫تحسين‬ ‫الثانوي‬ ‫الناقل‬ ‫مضاعفة‬ ‫و‬ ‫الخالصة‬ ‫الض‬ ‫االشارة‬ ‫بواسطة‬ ‫الراديوية‬ ‫االشارات‬ ‫تضمين‬ ‫الى‬ ‫االلياف‬ ‫عبر‬ ‫الراديو‬ ‫نظام‬ ‫يشير‬ ‫قناة‬ ‫عبر‬ ‫تنقل‬ ‫و‬ ‫وئية‬ ‫عبر‬ ‫الراديو‬ ‫نظام‬ ‫محاكاة‬ ‫و‬ ‫تصميم‬ ‫تم‬ ،‫المقالة‬ ‫ھذه‬ ‫في‬ .‫البعيدة‬ ‫النقاط‬ ‫إلى‬ ‫الرئيسي‬ ‫المركز‬ ‫من‬ ‫البصرية‬ ‫االلياف‬ ‫مع‬ ‫االلياف‬ ‫الموجي‬ ‫الطول‬ ‫تقسيم‬ ‫مضاعفة‬ ‫تقنيات‬ (WDM) ‫الثانوي‬ ‫الناقل‬ ‫مضاعفة‬ ‫و‬ (SCM) ‫مخططات‬ ‫مع‬ ‫مثل‬ ‫المختلفة‬ ‫التضمين‬ 4-QAM-OFDM) ، 16-QAM-OFDM ، 64-QAM-OFDM (‫قدرة‬ ‫لزيادة‬ ‫بنسبة‬ ‫النظام‬ 20 ×8 .‫البيانات‬ ‫معدل‬ ‫الثانية‬ ‫في‬ ‫جيجابت‬ ‫نظام‬ ‫ان‬ ‫المحاكاة‬ ‫نتائج‬ ‫بينت‬ ‫حيث‬ SCM-WDM-RoF ‫مع‬ 16-QAM-OFDM ‫مع‬ ‫افضل‬ ‫اداء‬ ‫يعطي‬ SER ‫تساوي‬ 10-9 ‫من‬ ‫ويقلل‬ ‫الطاقة‬ ‫استھالك‬ ‫مقارنة‬ ‫مع‬ ‫نظام‬ SCM-WDM-RoF ‫مع‬ ‫مخططات‬ ‫التشكيل‬ ‫األخرى‬ ‫استخدمت‬ ‫التي‬ ‫العمل‬ ‫ھذا‬ ‫في‬. ‫حزمة‬ ‫استخدامت‬ ‫وقد‬ ‫تدعى‬ ‫التي‬ ‫البرامج‬ "Optisystem Ver. 12" .‫النظام‬ ‫ھذا‬ ‫لمحاكاة‬ Fiber system capacity improvements-over-1417 INTRODUCTION adio-over-Fiber (RoF) systems can be described as the modulation process of microwave data signals onto an optical carrier and then transported to remote sites or base station using an optical fiber channel [1]. Radio-over-Fiber technology has been developed since the late 20 th century and has been used efficiently in a range of applications for communication systems such as cellular networks, WiMax, wireless local area networks (WLANs), cable television systems, indoor distributed antenna systems and other RF applications [2]. Radio over fiber system is the next generation of communication systems because it has many advantages compared with conventional system with low attenuation, a large bandwidth, immunity to radio frequency interference, operational flexibility, reduced power consumption, a long signal transmission distance and extension of existing coverage and capacity [3]. The main elements of the RoF system are; the Central Office (CO), the Optical Link and the Remote Node (RN) [4].