提出了一种新型的基于马赫-曾德尔调制器(MZM)和布里渊效应实现六倍频可调毫米波信号输出的方法。在本方案中,先调节MZM的直流偏置,抑制偶数边带,留下奇数边带;经过大功率掺Er3+光纤放大器(EDFA)放大之后,使两个一阶边带的功率达到布里渊阈值之上,然后采用了25km的单模光纤(SMF)作为布里渊介质,滤除一阶边带,留下三阶边带;最后经过EDFA放大和光电探测器(PD)光电转换得到六倍频的毫米波信号。因为布里渊边带滤波是窄带滤波,与波长无关,故本系统可以实现波长无关的微波信号产生。
A novel approach to generate sextupling tunable millimeter-wave(mm-wave) signals is proposed and experimentally demonstrated based on a Mach-Zehnder modulator(MZM) and a Brillouin-assisted sideband-filtering technique.In this scheme,the dc bias is tuned for the MZM to suppress even sideband,with odd sideband left.The power of two first-order sidebands can be higher then the Brillouin threshold after the Er3+-doped fiber amplifier(EDFA).Using the 25 km-long sigle-mode fiber(SMF) as Brillouin medium,first-order sidebands are filtered,with three-order sidebands left.Finally,the sextupling mm-wave signals can be achieved by the amplifying of EDFA and the optic-electric conversion of photo-detector(PD).As this stimulated Brillouin scattering(SBS)-assisted sideband-filter is narrow band filtering,independent of wavelength,a wavelength-flexible way of optical mm-wave signal generaton can be successfully realized.