Research On Remote Control Signal Analysis Technology Of UAV

Aiming at solving the problem of "black flying" of UAV,the analysis technology of UAV remote control signal is studied in this paper.The current mainstream UAV remote signal mainly adopts OFDM modulation,so as the research model,based on the OFDM signal to the traditional blind OFDM demodulation technology is analyzed,combined with the feature of UAV remote signal obtained the traditional blind demodulation technology applied to UAV remote signal analysis,and put forward the corresponding improvement methods for the existing problems.The specific research content can be divided into the following three aspects:1.The disadvantages of traditional OFDM blind demodulation technology applied to blind analysis of UAV remote control signal are studied.Firstly,the whole structure and specific components of OFDM blind demodulation process are introduced.Then the representative algorithm of each module in the blind demodulation process is studied,the principle of the algorithm is introduced and the preliminary simulation is carried out.Finally,the performance of each algorithm is simulated according to the characteristics of UAV remote control signal,and the simulation results show that the traditional blind demodulation method has the problem of insufficient estimation accuracy of sampling frequency and timing position when applied to UAV remote control signal analysis.2.The improved methods of OFDM signal sampling frequency blind synchronization and sampling timing blind synchronization are studied.An improved method for blind synchronization of sampling frequency based on symbol correlation is proposed.Simulation results show that compared with the traditional blind sampling frequency synchronization method,the improved method can achieve high precision sampling frequency deviation estimation under the condition of low Signal-to-Noise Ratio with less data,which is suitable for UAV remote control signals.An OFDM sampling timing blind synchronization method based on phase difference is proposed,and the algorithm principle is introduced and simulated.The simulation results show that compared with the traditional symbolic timing blind synchronization method,the algorithm can effectively eliminate the sampling timing deviation and realize the correct demodulation of UAV remote control signals.3.Blind equalization method of OFDM signal is studied.Aiming at the problem of blind demodulation of UAV remote control signal in multipath fading channel,blind equalization technology of OFDM signal is studied.In this chapter,the model of blind equalizer is introduced firstly,and then two common blind equalization algorithms,CMA and MCMA,are studied,and their performance is verified by simulation.To solve the problem of blind equalization of OFDM signals,an OFDM blind equalization algorithm based on frequency domain modification was proposed,and its performance was verified by simulation.The simulation results show that the proposed method can correct the influence of channel and sampling timing deviation simultaneously,and the estimation performance is good when the SNR is low,and it can be effectively applied to blind equalization of UAV remote control signals.Through the above research,this paper realizes a complete set of UAV remote control signal blind analysis technology,which can be effectively applied to the blind frame collection of non-cooperative UAV remote control signal,providing technical support for the construction of UAV recognition takeover platform.