通过将熔锥结构中强、弱耦合段的总幅度耦合系数与滤波网络方程中的幅度耦合系数等效的方法，定量分析了双环、三纤互耦滤波器的频谱特性。实验滤波器通带特性的测试结果与理论分析基本吻合。所测滤波器的中心波长、抑制度、半功率带宽及插入损耗分别为１．２７μｍ，＞１３ｄＢ、７２μｍ及３．９ｄＢ The spectral characteristics of the double loop, triple fiber filter are quantitatively analyzed by the method that is equivalent to the amplitude coupling coefficient in the filter network equations by the total amplitude coupling coefficient of the strong and weak coupling sections in the fused cone structure. The experimental results of the passband characteristics of the experimental filter are in good agreement with the theoretical analysis. The measured center wavelength of the filter, suppression, half-power bandwidth and insertion loss were 1.27μm,> 13dB, 72μm and 3.9dB