Bi-target tracking based on vortex wave with orbital angular momentum

This paper studies the application of vortex wave with orbital angular momentum (OAM) in the radar. The vortex waves can have eigenstates or modes with different integer topological charges, which are orthogonal to each other. The eigenstates with topological charges of 0, −1 and 1 were utilized in this paper. The radar transmitted the pulse with topological charge of 0 and received echoes with topological charges of 0, −1 and 1. The receiver can process the signals received by these orthogonal modes to obtain the azimuth and elevation angles of the two targets in a same range gate. Compared with the traditional mono-pulse radar only with sum beam and difference beam, this vortex-wave-based radar can track two targets in principle. This is meaningful for the application of the vortex wave.