| With the rapid development of UAV technology,the reduction of manufacturing costs and the convenience of performing tasks have led to more and more UAVs being applied to military and civilian fields,which not only provides convenience to people but also leads to a series of security problems.In order to realize the legal control of UAVs,it is particularly important to carry out the research on UAV jamming countermeasure technology,and it is also a hot spot and focus in jamming research at home and abroad.Aiming at the problem of how to select jamming strategies based on reconnaissance information to improve jamming efficiency in the current research,and considering the key role of the measurement and control link in the UAV system,this paper aims to achieve effective jamming of UAVs as combined with the use of adaptive frequency hopping anti-jamming method,the problem of jamming strategy of UAV measurement and control link is studied.The main work of the paper is as follows:Firstly,the composition and communication principle of the UAV measurement and control link system,as well as the commonly used jamming techniques and anti-jamming techniques are researched,which lays the foundation for the subsequent research on the jamming strategy of the UAV measurement and control link.Secondly,according to the communication characteristics of the UAV uplink using BPSK-FH mechanism,a carrier synchronization jamming method is proposed from the perspective of jamming the synchronization system.Based on the principle of Costas loop carrier synchronization,the loop locking performance under jamming is theoretically analyzed,and a simulation model was built to study the impact of conventional jamming,signals（broadband noise jamming,narrowband noise jamming,single-tone jamming,multi-tone jamming,noise FM jamming,and frequency sweep jamming）on the performance of carrier synchronization.Through analysis and comparison,the optimal jamming parttern and strategy of carrier synchronization jamming are obtained.From the perspective of jamming communication signals,when follower jamming cannot be implemented,the principle and performance of jamming signals commonly used in frequency hopping communication（broadband noise jamming,partial-band noise jamming,multi-tone jamming and multi-frequency BPSK jamming）are introduced and simulated respectively.Combining the analysis and research of jamming carrier synchronization and jamming communication signal,the jamming strategy selection of UAV uplink is given.According to the communication characteristics of the UAV downlink of the OQPSK mechanism,from the perspective of jamming communication signals,the jamming performance of common jamming patterns（broadband noise jamming,single-tone jamming,BPSK jamming and OQPSK jamming）is analyzed by building a jamming simulation model.Through simulation analysis,the optimal jamming pattern of OQPSK signal is obtained by comparison.Finally,aiming at the communication principle and characteristics of the UAV uplink data link using the adaptive frequency hopping anti-jamming method,the effect of the conventional jamming pattern to the adaptive frequency hopping system is obtained through simulation.On this basis,an adaptive partial-band noise jamming algorithm for adaptive frequency hopping is proposed,and its jamming performance is simulated and analyzed.The research shows that the algorithm can cause effective jamming to the adaptive frequency hopping system,and can significantly improve the interference effect compared with the conventional partial-band noise jamming under the condition of low jamming-to-signal power ratio and small jamming bandwidth.Finally,the jamming strategy of the UAV adaptive frequency hopping uplink is given. |
