通过对混沌系统特性的研究，设计出一种安全性高、加密速度快的通信加密方案。首先根据数字混沌序列的特性对混沌的迭代过程进行改进，实现对Chebyshev混沌序列的过抽样处理。设计语音信号传输系统，在发送端实现混沌序列对语音信号的加密，调制后进入高斯白噪声信道，在接收端接收到密文后对加密语音信号进行解调和解密，得到解密后的语音信号。实验证明，过抽样技术应用在混沌扩频通信中，可以极大地提高无线通信的保密性。
With the development of the multimedia and digital communication, people obtain increasingly more information and communicate with each other much more easily. For protecting information from eavesdropper, the encryption processing for large amounts of data is necessary. Although there are different demands for the encryption algorithm in different applications, however the demand for security and speediness are common. By studying the characteristic of chaotic system, a communication encryption program with high speed and security is designed. To construct encryption algorithm, some improvement has done on the chaotic iteration process according to the characteristic of digital chaotic, the oversampled to the Chebyshev chaotic maps (OSCM) is realized. Also, voice signal transmission systems were designed to encrypt the original voice signals by using the oversample of chaotic sequence at the sending port. After the modulation, the signals passed through the AWGN channel. The encrypted voice signals are demodulated and decrypted after receiving the ciphertext at the receiving port, and then the decrypted voice signal are received. Experiments show that the application of over sampling technology in the chaotic spread spectrum communication can greatly increase the confidentiality of wireless communications.
