提出了一种可用于绝对距离测量的波长扫描光纤干涉仪。在时域和频域上，对其输出信号进行了研究。理论分析了法布里－珀罗腔多光束干涉所产生的干扰以及扫描过程中波长的随机漂移对输出信噪比的影响。由此提出了外腔光源结构和加工精度的要求，并设计了相应的信号处理算法，达到了距离测量所要求的０．０５μｍ的精度和０．０１μｍ的分辨率 A wavelength-swept optical fiber interferometer that can be used for absolute distance measurement is proposed. In the time and frequency domain, its output signal was studied. The influence of the interference caused by the Fabry-Perot cavity multi-beam interference and the random drift of the wavelength during the scanning process on the output signal-to-noise ratio are analyzed theoretically. Therefore, the structure of the external cavity light source and its processing precision are put forward, and the corresponding signal processing algorithms are designed to achieve the precision of 0.05μm and the resolution of 0.01μm