Large-Scale Orbital Angular Momentum Radar Pulse Generation With Rotational Antenna

The electromagnetic (EM) wave with orbital angular momentum (OAM) has helical phase structure. This phase difference to the plane wave makes OAM wave with different backscattering coefficient, which can bring radar cross section (RCS) diversity for the radar application. However, due to the long distance in radar detection, e.g., even thousands of kilometers, the diversity gain fundamentally depends on large-scale OAM mode signal. Meanwhile, the OAM mode number in EM wave even reaches several thousands, which is quite difficult for traditional OAM wave generator. In this letter, large-scale OAM radar pulse generation with rotational antenna is proposed, so that RCS with different large-scale OAM wave can be achieved and the outstanding diversity gain is obtained.