Provided are an orbital angular momentum (OAM)-based transmitter, receiver, and communication method employing a radial concentric uniform circular array (UCA). The OAM-based communication method includes transmitting, by a transmitter, OAM multimode signals through a UCA-based transmitting antenna and receiving, by a receiver, the OAM multimode signals through a radial concentric UCA structure antenna including a plurality of UCA antennas. The plurality of UCA antennas each have the same number of antenna elements, and antenna elements having the same sequence number in the plurality of UCA antennas are on the same radial line in the radial concentric UCA structure antenna.