Constant-Envelope SC-FDMA for Nonlinear Satellite Channels

The increasing demand for broadband service delivery by satellite connections is still a challenge particularly due to the nature of the satellite channel. Multi-carrier techniques such as OFDM, OFDMA and SC-FDMA, which have successfully been deployed in terrestrial networks to achieve broadband access, present some limitations when applied to the satellite context. The main reason is their vulnerability to nonlinear distortions. In this paper we propose a novel multicarrier technique, called Constant-Envelope Single-Carrier FDMA (CE-SC-FDMA). In this technique, a nonlinear phase modulation is applied to an SC-FDMA signal rather than to an OFDM signal, as proposed by prior state-of-the-art contributions. At the receiver side, the phase demodulation is applied before the conventional SC-FDMA detection. Simulation results show that the proposed CE-SC-FDMA outperforms OFDM, SC-FDMA and CE-OFDM over nonlinear satellite channels. This improved robustness to nonlinear distortions makes CE-SC-FDMA a good candidate for future broadband satellite communication systems.