针对光纤环形激光器输出所表现出的复杂多纵模振荡现象，在实验研究中，采用光学外差并结合射频频谱仪的探测方法，对两种外加调制工作状态下光纤环形激光器的模式动态输出进行了实时测量与时频分析。通过对光纤环形激光器系统输出的总光强信息与探测范围内获取到的多纵模动态特性进行同步提取与时频分析，将光纤环形激光器输出动态特性的研究范畴从总光强表现出的低维混沌特性扩展到多纵模具有的高维混沌信息。根据实验结果分析多纵模强度随时间的演化行为与总光强输出的内在关联，以及掺铒光纤环形激光器输出在外部调制状态下的内在动力学特性。

In order to detect and analyze the complex multi-mode dynamics of fiber ring laser (FRL), in this experiment, based on the heterodyne detection method together with radio-frequency spectrum, the output of FRL intensities on two kinds of modulation condition are synchronously detected and analyzed. From the low dimension to high dimension chaos, the total intensity and multi-mode characters can be synchronously acquired. These experimental results show the relationships between real-time intensity and frequency evolution behaviors about single mode and total mode. Moreover, according to experimental results, the chaotic characteristics and inner relationships of erbium- doped fiber ring laser (EDFRL) output mode dynamic can be analyzed.