Design Of Receiving Algorithm OFDM Based Radar Communication Integration

With the development of technology,communications and radar equipment has a very wide range of applications in both military and civilian areas.In order to save equipment space and improve the use of the band and reduce the electromagnetic interference between devices,there is an urgent need for a device to achieve the function of communication and radar.With the continuous development of digital,as well as radar and communication using the frequency band is getting closer,radar communication integration system to achieve has a realistic basis.Radar communication integration has become a hotspot in these years.Integration research includes several hot spots,such as integrated signal design,radar-based integrated system implementation,and communication-based integrated systems.In the realization of communication-based integrated system,OFDM communication system is more representative.OFDM signal is widely used as a kind of signal system in communication,and has many advantages such as high bandwidth utilization,antimultipath and so on.OFDM signal in the field of radar applications have also been discussed for many years,and its good pulse compression characteristics,can be carried out well for radar speed rangefinder.However,OFDM signal loaded with random communication information,which leads to the generation of random side lobes,which seriously affects the performance of radar detection and the stability of the system.It is necessary to introduce some codes used in the multi-phase code radar to reconstruct the OFDM communication signal to suppress the generation of the random side lobe,but the communication rate of the modified OFDM signal will be greatly reduced.In order to realize the integration function based on communication system and take into account the performance of communication and radar as much as possible,this paper focuses on the research of OFDM-based radar communication integration without changing the form of OFDM communication signal.Firstly,in order to discuss the influence of random information on radar detection,the radar receiver performance is simulated and analyzed based on the matched filtering method commonly used in radar detection.Secondly,in order to eliminate the side lobe random fluctuation of communication information in radar information processing,the radar estimation algorithm based on periodogram method is used to realize the multi-objective distance and velocity estimation using the communication signal.In this paper,several superresolution algorithms are simulated and analyzed based on the OFDM signal of the 5.9GHz frequency band.The super-resolution performance of the target distance and velocity is discussed when radar detection is performed with a smaller bandwidth of the communication signal.Based on the analysis of the computational complexity of the MUSIC algorithm in the radar distance velocity joint estimation,a radar distance velocity joint estimation algorithm based on the root MUSIC algorithm is proposed,which reduces the computational complexity of the algorithm.In order to further solve the problem of MUSIC algorithm under coherent signal source and less number of snapshots,this paper proposes a scheme to introduce the idea of sparse decomposition into the receiver algorithm integrated radar communication based on OFDM.And the radar estimation performance of the sparse decomposition algorithm based on OMP and L1 SVD is compared.A two-dimensional joint estimation algorithm of radar distance based on sparse estimation is designed and implemented.