本文介绍了OFDM技术及其功率谱的，并通过仿真研究了OFDM的功率谱密度特点。在同样条件下，增大子载波数目，会使信号带宽增加，带外衰减加快，功率谱密度图形更加接近于矩形。另外，添加循环前缀将使离散峰值谱线的值略微增大。-This article describes the OFDM technology and its power spectrum, and to study the characteristics of the power spectral density of the OFDM simulation. Under the same conditions, increasing the number of subcarriers, and will increase in signal bandwidth, band attenuation accelerate, and power spectral density pattern closer to the rectangle. Further, the cyclic prefix is ​ ​ added the value of the discrete peak spectrum will increase slightly......