一种基于遗传算法的类语音调制方法

Speech-Like Modulation Method Based on Genetic Algorithm

提出了一种基于遗传算法的类语音调制方法。该方法采用数据波形映射法,将待调制数据用事先设计好的符号波形代替,从而构成类语音信号,其中符号波形的设计采用遗传算法。该算法在交叉部分利用所选择父本中的若干频率构成新的子代,以此来缩短仿真周期,然后再用新子代来代替上一次循环中适应度较低的码本符号进入下一次循环迭代中,从而获得最终想要的码本。为了降低误码率,在接收端用符号波形的时间平均来解调。实验结果表明,文章提出的方法在传输调制速率为2kbps的随机比特流时,符号错误率最低可为0.0007%。

The purpose of speech-like modulation is to modulate the input bit stream to a set of signals whose features are like voice waveform in order to transform in the voice channel. This paper presents a method of speech-like modulation based on Genetic Algorithm （ GA）. This method adopts the data waveform mapping to replace the modulated data with predefined waveforms so as to gener- ate speech-like signal. And the design of waveforms uses GA. In the crossover process of GA, it di- rectly chooses some frequency constituents of the parents to generate new offspring to shorten the pe- riod of simulation. Then, these offsprings are used to replace the symbols with lower fitness in the last cycle to reach the next loop iteration and the best symbol is obtained at last. In order to reduce the error rate, it uses the time average of symbol waveform to demodulate at the receiving end. Ex- perimental results show that the proposed method can realize a minimum symbol error rate （SER） of 0. 0007% when transferring random bits at the modulation rate of 2kbps.