提出了一种基于傅里叶域锁模光电振荡器（Fourier domain mode-locked optoelectronic oscillator，FDML OEO）的多波段可重构线性调频信号产生方案.在该方案中，由扫频多波长激光器、相位调制器和光陷波滤波器等构成FDML OEO的核心单元——快速扫频的多通带微波光子滤波器.将扫频多通带微波光子滤波器的扫频周期和FDML OEO的环腔延时同步，可实现傅里叶域锁模，从而在FDML OEO腔内自激振荡产生多波段线性调频微波信号.与传统的基于高速基带线性调频微波源的微波光子多波段线性调频信号产生方案相比，该方案结构简单，成本低，不需要借助外部的高速基带线性调频微波源.此外，FDML OEO所产生的多波段线性调频信号的带宽和中心频率均宽带可调.该新型多波段线性调频微波信号源在先进多波段雷达、多业务泛在接入无线通信等系统中具有良好的应用前景.
A photonic approach to generating reconfigurable multi-band linearly frequency modulated microwave waveform is proposed and experimentally demonstrated based on a Fourier domain mode-locked optoelectronic oscillator (FDML OEO). In the proposed system, a frequency scanning multi-passband microwave photonic filter (MPF) consisting of a frequency scanning multi-wavelength laser, a phase modulator and an optical notch filter is incorporated into the FDML OEO cavity. Multi-band linearly frequency modulated microwave waveform is generated at the output of the FDML OEO by synchronizing the scanning period of the MPF to the cavity round-trip time to achieve Fourier domain modelocking operation. The key significance of the approach is that it allows the generation of multi-band linearly frequency modulated microwave waveforms without using a highspeed baseband single-chirped microwave source. In addition, the central frequency and bandwidth of the generated waveforms can be easily reconfigured. The proposed approach has great potential in applications such as modern multi-band radar and multiple radio access wireless communication networks.
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