提出了一种采用加窗傅里叶变换的新型信号处理方法，用于提取基于白光光谱干涉相位型表面等离子体共振系统中的相位信息。首先，详尽阐述了这种提取相位信息算法的基本原理；其次，分析了算法中影响精度的几项主要参数，如窗口宽度、采样频率、阈值等，分析表明，只有选取恰当的参数才能得到理想的探测精度；最后，根据实际算取的光谱相位差值得出实际探测精度为3.894×10-7 RIU(折射率单位)。与之相对应的理论探测精度为3.905×10-7 RIU。理论精度和实验精度误差为0.28%。可以看出，这种算法具有很高的精度。另外，这种算法还具有简单、易与其他数值分析方法结合的优点。“,”A novel signal processing method based on windowed Fourier transform (WFT) was presented in a phase detecting surface plasmon resonance (SPR) system using spectral interference. The principle of this phase retrieval algorithm was introduced detailedly. The main factors which can affect the precision was analyzed, such as the width of the window, sample frequency, threshold value etc. Calculations indicated that, it can achieve a desired detection limit only by picking up the appropriate parameters. From the achieved spectral phase difference, the detection limit we obtained is 3.894×10-7 RIU, while the theoretical value is 3.905×10-7 RIU, the precision of this algorithm is 0.28%. It is seen that the algorithm presents a higher precision. In addition, the algorithm is mathematically simple and it can be readily combined with commonly used data analysis methods.