语音加密通信中类语音调制解调算法研究

Speech-like Modulation and Demodulation Algorithm in Speech Encryption Communication

针对当前移动通信网的安全缺陷和端到端通信方式存在多种安全问题,降低窃听的风险,保证端到端语音通信的安全性,研究语音加密通信中类语音调制解调算法。为保证加密后的语音数据能在正常在移动通信网中进行传输,主要借助OFDM技术,将加密后的语音数据承载到调制信号上,该信号的频率被限制在GSM声码器带通频率范围内,能以较小的失真通过GSM声码器信道,并且不引发VAD检测机制,解调端能相应的准确解调,从而实现数据抗声码器压缩传输。

For that there are many security problems in current mobile communication network and endto- end communication mode, and for reducing the risk of eavesdropping and ensuring the security of endto- end voice communication, a speech-like modulation-and-demodulation algorithm in speech-encrypted communication is explored. For the purpose to ensure the normal transmission of the encrypted voice data in the mobile communication network, with the help of OFDM technology, the encrypted voice data is loaded onto the modulated signal, and the frequency of this signal is limited to the bandpass frequency range of GSM vocoder. It can pass through the channel of GSM vocoder with a fairly small distortion without triggering the VAD detection mechanism. And the demodulator can accurately demodulate the signal, thus realizing the data anti-vocoder compression transmission.