| Authors: | |
| Rui Chen | |
| Hong Zhou | |
| Ji | |
| Ong Li |
One Sentence Summary:
achieve the minimum signal PAPR to maximize the PA efficiency
Abstract:
-Orbital angular momentum (OAM) multiplexing is considered to have the potential of further improving the spectral efficiency of communication systems. However, a common uniform circular array (UCA)-based multi-mode OAM communication system using discrete Fourier transform (DFT) and inverse DFT (IDFT) has high peak-to-average power ratio (PAPR), which reduces the radio frequency power amplifier (PA) efficiency and degrades system performance. In this paper, a constant envelope OAM (CE-OAM) system is proposed to achieve the minimum signal PAPR to maximize the PA efficiency. The transmitter using a phase modulator converts the high PAPR signal into constant envelope signal with 0dB PAPR, and the receiver performs inverse transform after OAM symbol detection, followed by the conventional OAM demodulation. Simulation results validate the feasibility of the proposed CE-OAM system and shows that CE-OAM system with appropriate modulation coefficient outperforms conventional OAM system in both PAPR and bit error rate (BER) performances. Index Terms-Orbital angular momentum, uniform circular array, peak-to-average power ratio, constant envelope.