为了在极低通信速率信道中实现保密语音通信,在北大西洋公约组织的0.6 Kb/s增强型混合激励线性预测声码器算法基础上,提出了基于混沌映射的保密通信算法。算法利用两个Logistic方程产生混沌序列,对声码器码流进行置换和移位。最后对该加密语音通信系统进行了仿真测试。测试结果证明,系统方案切实可行,产生的密钥空间大,能够实现加密强度较高的语音保密通信。
In order to realize the secret speech communication in an ultralow bit rate channel,a communication algorithm based on chaotic mapping and 0.6 Kb/s mixed excitation linear predictive speech coding algorithm standardized by North Atlantic Treaty Organization(NATO) is proposed.The chaotic series generated by two logistic equations are used for permutation and displacement for the coding bits of the speech coder.Simulation tests are carried out on this secret speech communication system.The results show that it can generate large key space and is applicable for high intension secret speech communication.