基于外部调制的光载毫米波传输特性研究-电子与通信工程专业论文.docx

AbstractAccording Abstract According to the shannon’S law,it Call provide greater storage capacity and communication bandwidth by improving the wireless signal carrier frequency．To meet the demand for high-speed wireless communication in future，Researchers focus in the high frequency of millimeter wave band．Radio over fiber technology not only effectively solves the problem of resources shortage in low frequency spectrum，it also bring up the wireless communication higher bandwidth and larger capacity．At present，the development of ROF technology is confronted by two major problems．On the one hand，the generation and the modulation of high frequency millimeter wave require high demands of device bandwidth．On the another hand，with the increasing carrier frequency，optical millimeter signal is vulnerable to the serious effect of fiber dispersion，limiting the fiber transmission distance．To solve two problems，this thesis uses the optical frequency multiplication technology and the improved single external modulation to study the transmission performance of ROF system，and use the Optisystem of optical communication software for simulation． Firstly，transmission performance of millimeter wave band(40 GHz， 60 GHz，1 00 GHz)in ROF system were studied．Using the traditional HI 万方数据 ememal ememal modulation，it compared the transmission performance of 40GHz， 60GHz and 1 00GHz millimeter-wave with quadruplicated frequency multiplication and octupled frequency multiplication．It analyzes the transmission performance of the system．Loading the 5GWs data rate of OOK signal，the transmission distance of millimeter wave which generates by quadruplicated frequency multiplication technology，is the double of octupled frequency multiplication technology．Thus，the performance of quadruplicated frequency multiplication technology is better．Loading the 2．5Gb／s data rate of OOK signal，the transmission performance of two kinds of millimeter wave frequency multiplication technology、system is r