Antenna Configuration and Carrier Frequency Dependence of System Capacity in Parabolic Reflector-Based OAM-MIMO

This study investigates the system capacity of an orbital angular momentum multiple-input multiple-output (OAM-MIMO) with a parabolic reflector, and assesses its effectiveness compared to a traditional uniform circular array (UCA)-based OAM-MIMO without a parabolic reflector. Specifically, we analyzed the system capacity when deploying a parabolic reflector on the transmitting side, considering parameters such as the number of multiplexed streams and carrier frequency. Furthermore, we examined the potential of OAM-MIMO with successive interference cancellation (SIC), which is crucial because of the differences in the received signal power among multiple UCAs that create spatial diversity. Our performance evaluation maintains a fixed total number of antenna elements and total transmission power, ensuring a fair assessment that considers the tradeoff between the stream power and bandwidth expansion effect resulting from an increased number of multiplexed streams.