论文部分内容阅读
数字调相信号是一类比较常见的数字通信调制信号,由于它的频谱利用率高,在通信领域中得到了广泛的应用。然而信号在传输过程中常常会受到噪声的干扰,噪声的存在会对后续过程调制参数的估计和解调造成不利的影响,严重时会使信号处理系统不能正常的工作。在这种情况下,必须采用信号处理的方法对信号进行去噪,抑制背景噪声以提高通信质量。由于经验模态分解(EMD)是一种自适应的方法,本文将经验模态分解算法应用于数字调相信号的去噪中。仿真实验结果也表明,对加入不同信噪比的数字调相信号进行EMD去噪,得到了较好的去噪效果,从而证明了这种方法的可行性与优越性。
Digital phase modulation signal is a kind of more common digital communication modulation signal, because of its high spectral efficiency, it has been widely used in the field of communication. However, the signal is often disturbed by noise in the transmission process. The existence of noise will adversely affect the estimation and demodulation of the subsequent process modulation parameters. In severe cases, the signal processing system can not work normally. In this case, the signal processing method must be used to denoise the signal and suppress the background noise to improve the communication quality. Since empirical mode decomposition (EMD) is an adaptive method, this paper applies empirical mode decomposition to denoising of digital phase-modulated signals. The simulation results also show that the EMD denoising of digital phase-modulated signals with different signal-to-noise ratios is achieved, and the better denoising effect is obtained. The feasibility and the superiority of this method are proved.