为提高通信的安全性,将多项加权分数傅里叶变换(multi—terms weighted-type fractional Fourier transform,MWFRFT)与变换域通信系统(transform domain communication system,TDCS)相结合,提出一种加权傅里叶变换域通信方法。首先使用MwFRFT对原信号进行处理;然后利用混沌序列产生的伪随机相位生成TDCS基函数;最后将所得信号与基函数调制并用于隐蔽通信。为验证该方法的可行性,对信号的星座变换特性以及相关特性进行了仿真分析,结果表明,MWFRFT具有较好的星座混淆性,利用混沌映射得到的TDCS基函数相关性有所提高,因此,该方法适用于隐蔽通信。
A new method combining the multi-terms weighted-type fractional Fourier transform (MWFR- FT) and the transform domain communication system (TDCS) is put forward to improve the security of commu- nication. Firstly, MWFRFT for sequence is used to process the original signals. Then chaos mapping is used to generate the pseudorandom phases of the basis function in TDCS. Finally, the basis function is modulated by MWFRFT signals in the covert communication. In order to show the accuracy of this method, the transforma- tion of constellation and the correlation performance are simulated and analyzed. The result shows that MWFR- FT has the diffusion and confusion property of constellation, and the new basis function has better correlation performance, so the method is suitable for covert communication.