In order to detect methane leakage accurately and prompt, a methane telemetry sensor is demonstrated based on near infrared absorption spectroscopy and optimized wavelength modulation technology. The distributed feedback diode laser is applied as the light source to cover the selected absorption line of 6046 cm⁻¹ to reduce the interference of CO₂ and H₂O. The waveform generator and the digital quadrature lock-in amplifier are constructed by the FPGA to produce driving signals and extract WMS-1f and 2f signals. And the “2f/1f” method is adopted to eliminate the environment influence such as light intensity fluctuations and improve the signal-to-noise ratio. This methane sensor has the characteristics of fast response and strong resistance to environmental interference and has great application prospect.

为了准确，及时地检测出甲烷泄漏，基于近红外吸收光谱和优化的波长调制技术，对甲烷遥测传感器进行了演示。分布式反馈二极管激光器用作光源，覆盖选定的6046 cm ^-1吸收线，以减少CO ₂和H ₂的干扰O.波形发生器和数字正交锁定放大器由FPGA构成，以产生驱动信号并提取WMS-1f和2f信号。并且采用“ 2f / 1f”方法来消除环境影响，例如光强度波动并提高信噪比。该甲烷传感器具有响应速度快，抗环境干扰能力强的特点，具有广阔的应用前景。