【摘要】 本文分析了矩形介质镜象波导特征方程的性质,得到以下结论:（1）E₁₁^y模是唯一的没有截止频率的模。因此,无论几何尺寸α、b及介质的相对介电常数∈_r,取何值,最低模式只能是E₁₁^y模;（2）E₁₂^x模的截止频率可由,式直接确定;（3）单模区相应的归一化波导高度B必小于1。大量的数值计算均与上述结论一致。更多还原

【Abstract】 The property of the characteristic equations of the rectangular dielectric image waveguide is analysed in this paper. The following conclusions are obtained: (1) Ey11 mode is the only mode without cutoff frequency; therefore the lowest order mode must be Ey11 mode -when geometric sizes a and b and relative dielectric constant Er, are chosen arbitrarily; (2) The cut-off frequency of Ex12 mode can be determined directly by using the formula fcx = C/(4b Er-1); (3) The height B of the normalized waveguide corresponding to single mode region must be smaller than 1, A series of calculated results are all in accord with the above-mentioned conclutions.更多还原