提出了一种运用多目标函数遗传算法的方向调制信号. 根据星座点之间欧氏距离与误码性能之间的关系，采用多目标函数综合相移器相移值，使得发射信号星座图在期望方位与基带数字调制信号相同，而在其他方位产生最大程度的畸变. 相比于传统的方向调制信号，用文中方法发射的方向调制信号具有更窄的波束宽度. 仿真结果表明，所提出的多目标方向调制物理层安全通信信号具有更强的防窃听性能.
A directional modulation signal based on multi-objective genetic algorithm is proposed. According to the relationship between Euclidean distance of constellation points and bit error rate performance, the phase shift values are generated by means of optimizing multi-objective genetic algorithm to synthesize a directional modulation signal. This signal transmits different signal constellation at different directions. In the desired direction, the signal’s constellation is the same as the traditional baseband modulation signal while the constellation is scrambled in other directions. Compared with the traditional directional modulation signal, the proposed directional modulation signal has a narrower beam-width. Simulation results show that the technique
offer a better physical layer secure transmission signal for wireless communication.
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