| Digital beamforming and spatial spectrum estimation(angle estimation)are two main aspects of array signal processing.Beamforming can generate multiple independent and controllable beams at the same time.Each beam only receives the corresponding spatial angle signal,which is equivalent to a spatial filter.This helps to simplify the subsequent signal processing.Spatial spectrum estimation can estimate the direction of arrival of the target signal and determine the spatial angle of the target.LFMCW radar has excellent performance in ranging and velocity measurement,and can accurately estimate the distance and velocity of the target.However,when estimating multiple targets,it is necessary to pair the spectrum of the up-and-down sweep beat signal.Only accurate pairing can accurately estimate the distance and speed of the target.Therefore,the frequency spectrum matching of LFMCW radar is highly demanded.If array signal processing is combined with LFMCW radar to receive only one target echo signal in each beam while suppressing the echo signal of other targets,the complex matching problem is solved without pairing.At the same time,it has important application value to estimate the distance,velocity and angle of the target.Based on this idea,this paper carries out relevant research,the main work is as follows:1.Firstly,the principle of digital beamforming is analyzed.Several classical robust adaptive beamforming algorithms and beamforming algorithms in recent years are introduced and compared.2.Then,based on the theoretical analysis of digital beamforming,the spatial spectrum estimation theory is introduced,and the spatial spectrum estimation and super-resolution algorithms based on digital beamforming are analyzed,and their applications in angle estimation are compared.3.The principle of LFMCW radar ranging and velocity measurement is analyzed theoretically.4.The hardware implementation system framework of FPGA is designed,and several groups of data are tested and verified. |
PDF Full Text Request