基于DDS技术的可调谐二极管激光器调制电路设计

Design of modulation circuit for tunable diode laser based on DDS

可调谐二极管激光吸收光谱(TDLAS)技术由于其高灵敏度、高分辨率、快速响应及非接触式遥测等诸多优点而被广泛应用于环境、工业安全和过程控制等领域,但是,目前还没有通用的TDLAS系统调制电路。本文介绍了基于DDS技术的、适用于各种TDLAS系统的通用调制电路设计。主要设计思想是使用单片机控制DDS和D/A芯片,得到系统所需的正弦和锯齿波信号。经实验证明,该电路输出信号稳定度高、噪声小,能够满足调制激光器的要求。同时也可作为高精度的频率信号源,应用于各种电子测量设备中。

Tunable diode laser absorption spectroscopy （TDLAS） technology is widely applied in environment, industrial safety,process control and other realms due to its advantages such as high sensitivity, high selectivity, quick response, on-line measurement, non-contact remote measurement and so on. But there was no current modulate circuit for TDLAS system. The design of modulation circuit for tunable diode laser based on DDS has been introduced. The main idea of design is using MCU to control DDS and D/A chips, so we can get sine wave and saw tooth signals. It has been proved by experiments that the signals are stable and with low noise, it can meet the needs of tunable diode laser modulation. The circuit also can be used in many kinds of electronic measure equipement as high solution frequency signal source.