Directional Modulation Signal Generation Technology Based on Microwave Photonics

In order to solve the problems of slow scanning speed, small bandwidth, and high loss of traditional directional modulation, a directional modulation signal generation technology based on microwave photonics is proposed. By reasonably controlling the DC bias of the two modulators of the Dual-Parallel Mach-Zehnder Modulator (DPMZM), the directional modulation signal required by the antenna can be generated. The transmission and demodulation are simulated to evaluate the quality of the generated signals. The results show that the expected receiver successfully recovers the symbol information, and the signal-to-noise ratio reaches 25 dB. Meanwhile, the recovered symbol information is out of phase at the eavesdropping receiver, and the power is low. This shows that the system realizes the basic function of directional modulation.