Research On Radar Communication Integration Technology Based On Variable Scale OCD

In recent years,with the rapid development of radio technology,the spectrum resources are decreasing.At the same time,there are more and more similar structures between radar and wireless communication systems,which makes it possible to integrate radar communication technology with high spectral efficiency,low system redundancy and energy consumption.The Joint Radar Communication(JRC)system based on orthogonal multi-carrier signals has attracted widespread attention due to its superior performance.However,the Doppler effect caused by high-speed moving scenes and high-speed targets will lead to a sharp deterioration of the wireless communication and radar detection performance of such integrated systems.The key technologies of orthogonal multi-carrier JRC that can suppress the Doppler effect are studied.The main contents include the following three aspects.1.The echo model based on Orthogonal Frequency Division Multiplexing(OFDM)is constructed,and the intra-symbol Doppler effect of OFDM caused by high-speed targets is analyzed.A new Scaled Discrete Fresnel transform(SDFn T)is proposed,and proposed a new radar signal processing method that can suppress the intra-symbol Doppler effect based on SDFn T.The algorithm uses SDFn T to map the random communication data to the chirp axis,and adjusts the slope.The algorithm can eliminate the intra-symbol Doppler effect while removing the communication data.The simulation results show that the algorithm has excellent high-speed target detection performance.2.In view of the high computational complexity of the commonly used OFDM inter-carrier Doppler effect suppression algorithm,a new inter-carrier Doppler effect compensation algorithm based on SDFn T-SCIF(Scaled Inverse Fourier transform)is proposed.This algorithm uses the low-complexity SDFn T to replace the Fractional Fourier transform(Fr FT),and optimizes the original algorithm,which omits the unnecessary traversal times.The simulation results show that this algorithm can greatly reduce the computational complexity under the premise of ensuring the detection performance.3.A new integrated signal based on Scale Transform-Orthogonal Chirp Division Multiplexing(ST-OCDM)is proposed,and a new JRC system based on ST-OCDM is constructed.The random communication data are modulated in the chirp domain with variable modulation slope at the transmitter of the system,and the same demodulation method is used in the radar processing of the communication processing at the receiver,which not only simplifies the structure of the integrated system,solves the problem of the decline in radar detection performance caused by high-speed motion,but also greatly improves the communication performance of the system.The simulation results show that the system structure is simple and can effectively solve the problem of Doppler effect.It also shows superior radar detection and wireless communication performance and has great application value.