This digitalized optical fiber transmission system is upstream line of the bi-directional optical fiber transmission system .

数字化光纤传输系统，为 有线制导光纤传输系统的一个部分；

Based on the built double-sideband suppression upstream system optimum system parameters are found by comparing the relationship between OSNR ( Optical Signal to Noise Ratio ) modulated signal intensity laser spectrum line width frequency offset and system performance .

针对所搭建的双边带抑制载波的 上行系统通过比较光信噪比、调制信号强度、激光器谱 线宽度和频率漂移对系统性能的影响，寻找出上行系统的最佳参数配置。

Because the average users use the net mainly to download data ADSL proposes the way of making the rate of downstream bigger than the upstream according to the realistic situation . As a result Asymmetric Digital Subscriber Line came out .

由于普通用户上网时主要是下载数据，所以ADSL根据这种现实情况提出下行速率大于 上行速率的方式来提供用户上网，此即不对称数字用户 线的由来。

The effectiveness of upstream FEM is validated by both analytical solution of coaxial cylinder structure and the measured data from experimental transmission line .

同轴圆柱结构的解析解和实验 线路的测量数据验证了该方法的有效性。