提出一种用于水下测距的混沌调制激光雷达方案，并进行了实验验证。该方案利用布尔混沌电路产生的混沌电信号调制半导体激光器，获得532 nm混沌激光，并将其分成两束，分别作为探测光信号和参考光信号。将探测光信号入射到1.5 m×0.3 m×0.3 m的水槽中，直接照射水下探测目标。经目标反射回的探测光信号和参考光信号分别经过光电探测器转换成电信号，再利用相关运算即可获取水下目标的距离。经过原理性实验验证，获得的最小和最大探测距离分别为0.14 m和1.36 m，距离分辨率为51 cm，目标测距结果的平均误差在2.3 cm以内。该混沌调制激光雷达具有测量盲区小、结构简单的特点，可作为一种新的水下目标测距技术。

A chaotic modulation lidar for underwater ranging is proposed and demonstrated experimentally. The 532 nm chaotic laser is generated by a chaotic electrical signal produced by a Boolean chaotic circuit directly modulating the diode laser. It is divided into two beams as the probe light and the reference light signal, respectively. The probe light signal is injected into a water tank of 1.5 m×0.3 m×0.3 m to directly illuminate the underwater target. The probe light reflected from the target and the reference light are separately converted into the electrical signals by the photoelectric detector. The distance of the underwater target can be achieved by the cross-correlation between both of the electrical signals. Through the theoretical experiment demonstration, the minimum and maximum detection distance of 0.14 m and 1.36 m are obtained respectively. The range resolution is 51 cm and the average error of the target ranging results is within 2.3 cm. The chaotic lidar can be a new technology of underwater ranging owing to its essential characteristics of the small measuring blind area and the simple structure.