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Abdelmoula BEKKALI Pham Tien DAT Kamugisha KAZAURA Kazuhiko WAKAMORI Mitsuji MATSUMOTO Takeshi HIGASHINO Katsutoshi TSUKAMOTO Shozo KOMAKI
With the increase of communication demand and the emergence of new services, various innovative wireless technologies have been deployed recently. Free Space Optics (FSO) links combined with Radio over Fiber (RoF) technology can realize a cost-effective heterogeneous wireless access system for both urban and rural areas. In this paper, we introduce a newly developed advanced DWDM Radio-on-FSO (RoFSO) system capable of simultaneously transmitting multiple Radio Frequency (RF) signals carrying various wireless services including W-CDMA, WLAN IEEE802.11g and ISDB-T signals over FSO link. We present an experimental performance evaluation of transmitting RF signals using the RoFSO system over a 1 km link under different deployment environment conditions. This work represents a pioneering attempt, based on a realistic operational scenario, aiming at demonstrating the RoFSO system can be conveniently used as a reliable alternative broadband wireless technology for complementing optical fiber networks in areas where the deployment of optical fiber is not feasible.
Sermsak JARUWATANADILOK Urachada KETPROM Yasuo KUGA Akira ISHIMARU
Point-to-point optical and millimeter wave communication has recently been of interest, especially in urban areas. Its benefits include simpler and easier installation compared with a land-based line. However, this technology suffers when adverse weather conditions are present, such as rain, fog and clouds, which induce scattering and absorption of the optical wave. The effects of scattering and absorption degrade the quality of the communication link resulting in increase of bit-error-rate. Therefore, there exists a need for accurate channel characterization in order to understand and mitigate the problem. In this paper, radiative transfer theory is employed to study the behavior of amplitude modulated signal propagating through a random medium. We show the effect of the medium to a modulated signal and relate the outcome on the quality of the communication link.