Resolution Performance of the Orbital-Angular-Momentum-Based Imaging Radar

This letter studies the resolution performance of the novel imaging radar based on the electromagnetic wave with orbital angular momentum (OAM). Based on the same circle baseline or synthetic circle baseline, the point-spread functions (PSF) in azimuth domain of the OAM-based imaging radar and the conventional imaging radar are compared by analyzing and numerical computing. The signal-to-noise ratio (SNR) processing gain is also analyzed. The results show that the OAM-based transmitting-receiving imaging radar and the conventional imaging radar have the same PSFs in the azimuth. Thus, they have the same geometrical resolution in principle. The results also show that they have the same SNR processing gain when the uniform circular array is used to generate the OAM. It is concluded that the resolution performance of the OAM-based imaging radar is equivalent to the conventional imaging radar when the OAM-based imaging radar can be regarded only as a special processing method.