Directional Modulation (DM) technique is one of the research hotspots for wireless network physical layer security communication. Due to the bad information beam-width and information disclosure of side lobe, DM signal has low safety performance and high complexity. The Woodward-Lawson method is applied to the directional modulation in this paper to reduce the bit error rate of the receiver and the complexity of the algorithm. Firstly, the desired target signal distribution function is set up to strengthen the distortion of the far-field distribution in the desired direction. Then, Woodward-Lawson method is used to get the weighted value of the emitter array. Finally, the algorithm is simulated by Matlab and the simulation results show that the proposed algorithm provides a better information beam-width compared to the traditional wireless communication. It solves the problem of information disclosure of side lobe, and has a higher security performance.