Aircraft Secure Tracking Telemetry And Command Technology Based On Directional Modulation

Directional modulation is a physical layer security communication technology,which can make the received signal in the desired direction demodulate normally,and the re-ceived signal in the undesired direction be disturbed,so as to realize the secure transmis-sion of the secret signal.It has a wide range of application prospects in the field of aircraft tracking telemetry and command.Based on the relevant scenarios of aircraft secure track-ing telemetry and command,this paper conducts an in-depth study of its signal system,and has the following work:First of all,in view of the weak anti-interference ability of traditional directional modulation technology and the problem of not adapting to wideband signals,a direct se-quence spread spectrum directional modulation method based on the Farrow structure delay filter is proposed.The simulation results show that the method overcomes the aper-ture effect through delay and transmits the direct sequence spread spectrum signal to the desired direction without distortion,which improves the anti-interception ability of the direct sequence spread spectrum measurement and control signal.Secondly,in view of the difficulty of using high-power amplifiers for traditional directional modulation signals and the excessive leakage range near the desired direction,a continuous phase directional modulation method based on high-efficiency interference waveforms is proposed.The simulation results show that the waveform designed with the help of the communication interference field idea can more effectively interfere with the signal in the undesired direction,and improve the safety problem caused by the excessive leakage range of the continuous phase modulation measurement and control signal.Finally,in view of the application of directional modulation technology,the system framework of directional modulation prototype is designed,and the two key modules of channel correction and baseband synthesis are realized.The results show that the signals between the channels at the transmitter are corrected in phase and have small amplitude differences.The FPGA-based baseband synthesis algorithm and computer simulation results have a small error,which meets the engineering requirements.