为了得出传输模拟信号的双线传输线内外电磁场与电磁波的解析解，该文基于麦克斯韦方程组从TEM波、TM波、TE波的角度对双线传输线内外的电磁场进行了计算. 结果表明，在双线传输线内外所传播的电磁波为TM波，双线传输线内电磁场与电磁波的解析解由0阶和1阶复宗量贝塞尔函数构成，双线传输线外电磁场的解析解由0阶复宗量贝塞尔函数和0阶复宗量诺依曼函数构成，同时，该文给出了双线传输线内电磁场的系数与电流的关系. 为双线传输线内外电磁场与电磁波的拟合计算、仿真及信号失真、电磁兼容分析提供了依据.

 To determin the analytical solutions of electromagnetic field and wave in and out of two-wire transmission lines transmitting analog signal，electromagnetic field and wave in and out of two-wire transmission lines is analysed and calculated based on maxwell equation from the angle of TEM wave，TM wave and TE wave in this paper.The results show that TM wave is transmitted in and out of two-wire transmission lines. The analytical solutions of electromagnetic field and wave in two-wire transmission lines consist of zero and 1st-order complex variable bessel functions，the analytical solutions of electromagnetic field and wave out of two-wire transmission lines consist of zero-order complex variable bessel functions and 1st-order complex variable Neumann functions，the relationship between electromagnetic field coefficient and electric current is given in this paper.The results further support for fitting calculation，simulation，signal distortion，electromagnetic compatibility analysing.