A Two-Dimensional Imaging Method Of Vortex Electromagnetic Waves Using FDA Radar

In this paper, a two-dimensional imaging method of vortex electromagnetic waves based on frequency diverse array (FDA), which generates time-varying orbital angular momentum (OAM) modes, is analyzed. Based on the FDA-OAM model, the different mode vortex electromagnetic wave beam can be obtained at the target point by setting different array parameters and sampling times. In this paper, a time-varying OAM beam based on a circular FDA array is designed, which enhances the flexibility of the vortex electromagnetic wave mode and shows the unique advantage of FDA in OAM beam formation. In addition, the multiple signal classification (MUSIC) algorithm is introduced in this paper to realize the 2D imaging of single target and multiple target point distance and azimuthal direction, which eliminates the angular aliasing phenomenon during fast Fourier transform (FFT) imaging under Multiple-Input Multiple-Output (MIMO) structure. The simulation results verify that the proposed FDA-OAM can realize the high-resolution imaging of target distance and azimuthal direction.