基于GSM语音的汉字隐秘传输方法

给出了一种基于GSM（global system for mobile communication）语音的机密汉字隐秘传输方法.该数据隐藏方法选择对每帧GSM语音信号中对人的听觉最不敏感的69 bits,最多改变1bit,便可以嵌入6 bits的机密数据.采用该方法可以在规则脉冲激励长时预测编码（RPE-LTP）语音中,每秒隐藏300 bits的机密汉字数据.由于该算法采用二级加密,因此,具有很好的安全性.该信息隐藏方法已通过局域网隐秘传输模拟实验,嵌入机密汉字信息后的语音具有较好的峰值信噪比（peak SNR,PSNR）,信号的平均失真（normal average distortion metrics,NADM）也很小.

Covert communication method of Chinese characters based on GSM speech

A novel covert communication method of secret Chinese characters based on GSM speech was proposed.The data hiding method can embed as many as 6 bits of covert data by changing,at most,1 bit in these most imperceptible 69 bits in each frame of the GSM speech.Using the proposed scheme,as many as 300 bits of secret Chinese characters data per second could be concealed in the RPE-LTP speech signal.Because the algorithm was based on two levels encryption,it guaranteed a very high level of security.The method was simulated in local area networks,which shows that the speech embedded secret Chinese characters have better PSNR(peak SNR) and the NADM(normal average distortion metrics) of the signal is very small.