摘要
为了抑制扩频通信中存在的大量干扰,构建了直接序列扩频系统抗线性调频干扰(Linear Frequency Modulation,LFM)模型,重点对基于分数阶傅立叶变换(Fractional Fou-rier Transform,FRFT)的时频滤波算法及其改进算法的性能作了仿真和分析.仿真结果表明,这类算法对于LFM类的信号可获得明显的噪声抑制效果,并具有良好的幅度保持性.更为重要的是,FRFT是一维的线性变换,可以用FFT(Fast Fourier Transform)来实现;在处理多分量信号时,FRFT不仅在计算上大为简化,而且不受交叉项的困扰.
In order to suppress the existence of a large number of spread-spectrum communications interference, build a DSSS （Direct Sequence Spread Spectrum） model of linear frequency-modulated interference is built by the method of FRFT（Fractional Fourier Transform） which is on time domain. The capability of the improved algorithm is modeled and analyzed. Result showes that the proposed algorithm distinctly obtains the better noise suppression performance about signal of LFM （Linear Frequency Modulation）. Because FRFT（Fractional Fourier Transform） can be implemented by FFT （Fast Fourier Transform）, comparing with other filtering algorithms, it is both easier in computation and never disturbed by cross terms.
出处
《西安工业大学学报》
CAS
2009年第5期471-474,共4页
Journal of Xi’an Technological University
