基于最近邻比较和中值滤波的拉曼光谱spike自动检测及剔除方法研究

激光拉曼光谱技术具有原位、实时、多物质同时探测的优点，在实验室内已经得到了广泛研究，并逐渐应用于深海海底等极端环境下的原位探测。由于CCD等光谱探测器可能受到宇宙射线的干扰，会在拉曼谱图上形成位置随机的spike，对拉曼光谱分析造成干扰。将最近邻比较和中值滤波相结合的方法应用于海水实测拉曼光谱spike的检测剔除，首先将原始拉曼光谱分为拉曼峰区域和非拉曼峰区域，对拉曼峰区域使用最近邻比较法处理，对非拉曼峰区域使用中值滤波方法，结果显示该方法能将非拉曼峰区域和拉曼峰区域的spike完全剔除，没有出现误检和漏检，且不会对拉曼特征峰强度产生影响，有助于提高拉曼光谱定性定量分析的精确性和稳定性。

Spike Detection and Removal of Raman Spectra by the Method Combined Nearest Neighbor Comparison with Median Filter

Laser Raman spectroscopy is widely applied in marine chemical environmental detection and analysis of substances, as an in-situ, real-time, multi- substances detection sensor technology. Charge-coupled devices (CCD) as the detector of Raman spectrometer are easily interfered by cosmic ray so that some spikes that have random location ,intensity and peak width occur on Raman spectra. The presence of such spikes can damage spectral presentation, complicate interpretation, and impede further analyses. The method combined nearest neighbor comparison method（NNC）with median filter was used to detect and remove spike from the measured spectral data of seawater in laboratory. The Raman spectra were divided into two areas firstly: Raman peaks area and the area that has no Raman peaks. The NNC processed the area that has Raman peaks and the median filter processed the area that has no Raman peaks. The result shows that the combined method can remove spike of the full spectra completely on the premise that the intensity of Raman peaks remain unchanged. The method contributes to improving the accuracy and stability of qualitative and quantitative analysis for Raman spectra.