数字信号在语音信道的抗干扰研究.doc

文档介绍：
数字信号在语音信道的抗干扰研究#
王涛,王勇**
(西安电子科技大学通信工程学院,西安 710071)
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摘要:语音安全是目前广泛使用的移动通信系统安全研究的重要方面,语音加密是实现端到
端语音安全通信的有效措施,而加密后的语音数据和加密所用的数据不能直接在移动话音信
道中传输。针对这一问题,本文研究了 LTP-RPE 声码器信道的时频特性,提出运用 PSK 调
制方式将数据调制到低频正弦载波上进行传输的方案。经仿真结果验证,LTP-RPE 声码器
信道在低频域频率响应近似线性,幅度响应非线性,当载波频率范围在 100~1200Hz 内并且
振幅小于 时,通过 PSK 调制方式传输数据具有极低的误码率,能满足在话音通道上端
到端的数据数据传输要求。
关键词:数据传输;声码器;移频键控;误码率
中图分类号:
Research of Anti-interference of Digital Signal Pass-through
Voice Channel
Wang Tao, Wang Yong
(School of munications Engineering, Xidian University, Xi’an 710071)
Abstract: Voice security is an important aspect of the researches on the security of the widely
used munication encryption is an effective method to encrypt human
voice and realize the end-to-end secure munication,but the data of encrypted speech or
used to encrypt speech can't be directly transmitted on voice channel. In order to solve this
problem,this paper researches the time frequency features of the LTE-RPE vocoder channel ,and
proposes a method that the data are transmitted after being modulated to low frequency sine
carriers using PSK modulation. It is verified by simulation results that the frequency response of
LTP-RPE vocoder in low frequency domain is approximate linear ,the amplitude response of
LTP-RPE vocoder is non-linear,and the BER is very low if data are tranmitted