A Novel Detection Scheme for the Discrete Body of Revolution With Fractional Orbital Angular Momentum Beams

A novel detection scheme with fractional orbital angular momentum (OAM) beams is proposed in this communication, so as to predict the rotational velocity of the discrete body of revolution (DBoR). At first, the echo model of DBoR is derived under the incidence of integer OAM beams. The theoretical derivation shows that some integer OAM modes may not work for the detection of DBoR due to echo cancellation. Then the echo model with fractional OAM modes is also derived. It shows that the echo frequency spectrum with the fractional OAM always includes effective integer OAM modes. Consequently, a novel detection scheme with fractional OAM for DBoR is proposed. It should be noted that all these theoretical derivations are based on ideal scattering points. Finally, 3-D full-wave simulations of a practical DBoR target are conducted with the method of momentum (MoM) and its fast algorithm. Numerical results demonstrate the effectiveness of the proposed detection scheme. It can be used as an efficient tool to analyze the rotation characteristics for DBoR targets.