波分复用无源光网络具有支路多、节点密的特征，为精确定位各支路的断点，提出了一种基于可调谐混沌Fabry-Perot激光器的检测方法.将光反馈多纵模Fabry-Perot半导体激光器作为混沌光源，在改变反馈光光波模式的条件下输出波长可调谐的混沌激光.以探测光的波长标记各被测支路，将探测信号和携带延时信息的回波信号进行互相关运算，根据相关曲线峰值的位置即可完成定位.分析了可调谐混沌源的特性，并以1×4的波分复用无源光网络为例，进行了初步的实验验证，结果表明该方法可以精确定位光网络支路中连接点及断点的位置，空间分辨率达4 cm，且与探测距离无关.

The main characteristic of WDM-PON is the node-tree structure. In order to preciously locate faults in each branch, a method based on tunable chaotic Fabry-Perot laser is proposed. Chaotic light emitted from a optical feedback multiple-longitudinal mode Fabry-Perot semiconductor laser diode is utilized as the probe beam. By selecting the feedback mode, a tunable chaotic laser is obtained. The branches of the optical networks are distinguished by the laser′s wavelength, and fault location is realized by calculating the cross-correlation of transmitted and back-reflected signals. In the experiment, we analyse the chaotic property and take a 1×4 ITU WDM-PON to be detected, the measurement results show that the breakpoints and connectors could be preciously located, an rang-independent spatial resolution within 4 cm are achieved with this method.