A Comparative Study Between SC-FDMA and OFDMA Schemes for Satellite Uplinks

This paper presents a detailed comparative study of two single-carrier frequency-division multiple access (SC-FDMA) schemes, namely localized FDMA scheme (LFDMA) and interleaved FDMA scheme (IFDMA), versus orthogonal FDMA scheme (OFDMA), for a satellite uplink. The air-interface of the latter is based on the digital video broadcasting (DVB) family of standards. Considering two state-of-the-art high power amplifiers (HPAs), operating in the K- and S-bands, the performance of synchronous and asynchronous LFDMA, IFDMA and OFDMA is evaluated in a multi-user environment. Systematic comparison results show that although for synchronous reception IFDMA outperforms the other two schemes, for asynchronous reception it is the most sensitive to degradation caused by inter-block interference (IBI). Furthermore, due to its relatively large envelope fluctuations, OFDMA is the most sensitive scheme to non-linear distortion. Although for synchronous reception LFDMA shows only slightly inferior performance as compared to IFDMA, it outperforms the other two schemes for the asynchronous reception considered, especially for increased IBI distortion.