通过搭建的测量实验平台，获取了甲烷6 046.96 cm^-1处高压气体吸收光谱.通过经验模态分解算法减弱了高压引起窗片形变而产生的探测噪声，吸光度信号的均方根误差（RMSE）降低了3.87倍，通过洛伦兹线型拟合算法获得的吸光度拟合残差优于±1%.研究表明，谱线线宽随着压力增大而增大，计算的高压环境的氮气-甲烷分子的互展宽系数为0.063 1 cm^-1atm^-1.此外，随着压力的增大，吸收线出现“红移”现象，计算得到氮气诱导压力频移系数为-0.008 48 cm^-1atm ^-1.由此提出一种利用检测波长、压力和压力频移系数的线性关系反演高压环境下气体浓度的算法.总之，高压环境下光谱展宽特性研究为工业环境下的光谱检测打下基础.

The high-pressure absorption spectrum at 6046.96 cm^-1 of methane was obtained with the measurement experimental platform. The empirical mode decomposition algorithm was used to filter out the detection noise caused by window deformation at high-pressure. Consequently， the overall root-mean-square error （RMSE） of absorbance signal was reduced by 3.87 times， and the residual error of absorbance signal fitting was lower than ±1% by using Lorentz line-type fitting algorithm. These studies showed that the absorption line width increased with the pressure increasing， and the mutual broadening coefficient of nitrogen-methane molecules at high-pressure was calculated as 0.0631 cm ^-1atm ^-1. Moreover， the absorption line appeared a "red shift" phenomenon as the pressure increasing， and the pressure shift coefficient of nitrogen-induced was calculated as -0.00848 cm ^-1atm ^-1. Therefore， a method of concentration inversion at high pressure was proposed by the linear relationship between the detection wavelength， pressure， and pressure shift coefficient. In conclusion， the research on spectrum broadening characteristics in high-pressure environment lays foundation for spectrum detecting in industrial environment.