北京锦坤科技有限公司 www.jonkon.com.cn (详细介绍见PDF文件) 摘要:实验研究了一种基于相位调制器(PM)并级联强度调制器(IM)实现40 GHz毫米波传输正交频分复用(OFDM)信号的光纤无线通信(ROF)系统。在中心站,采用20GHz的射频(RF)信号驱动PM,调节驱动信号的强度,使输出的信号经光纤布拉格光栅(FBG)滤除中心载波后再送入IM。2.5 Gbit/ s的OFDM信号直接调制在光毫米波上,经过50km标准的单模光纤(SSMF)传输到基站。在基站,光调制信号经光电转换器(PD)转换成电调制信号,再与RF信号混频,恢复出基带OFDM信号。实验结果表明,在无色散补偿、误码率(BER)为10- 3的条件下,下行链路中2.5Gbit/ s的OFDM信号经光纤传输50km后,其功率代价小于1dB,而且信号的星座图依然较好。 关键词:光纤无线通信(ROF) ; 光毫米波信号; 相位调制器(PM) ; 正交频分复用(OFDM) 中图分类号:TN929.11;TN761 文献标识码:A 文章编号:100520086(2010)0320383204
Experimental researchabouta40GHzorthogonal frequencydivi2 sionmultiplexingradio2over2fiber systembasedonoptical phase modulator LI Zhi2lan, CAOZi2zheng, DONGZe, CHENLin 33 (KeyLaboratoryof Micro/ NanoOptoelectronicDevicesof EMC,School of Computer andCommunication,HunanUniversity,Changsha,410082,China) Abstract:Wedemonstratea40 GHzradio2over2fiber systemusinganoptical phasemodulatoralongwith anintensitymodulatortogenerateanoptical millimeter2wavewithOFDMsignals. Inthecentral station,40 GHzoptical millimeter2wavewithOFDMsignals is generatedbyusinganoptical phase modulator whichis drivenbythe20 GHzRFsignals. Thentheoptical carrierisfilteredout byanFBG.2.5 Gbit/s OFDMsignalsaremodulatedon40 GHzoptical mm2wavedirectlyandtransmittedtothebasestation over50kmstandardsingle2modefiber(SSMF). Inthebasestation,theoptical mm2wavesignalsarecon2 vertedtoelectrical signalsafteroptical2electrical conversion,andthedown2convertedOFDMsignals are detectedafter mixingwiththelocal oscillators. Theexperimental results showthat at the BERof 10 23 andwithout dispersioncompensation,thepowerpenaltyof thedownlinkOFDMsignalstransmittedover 50kmSMF228islessthan1dB,andtheconslationfigureis still good. 北京锦坤科技有限公司 www.jonkon.com.cn |