Constant-envelope SC-FDMA for nonlinear satellite channels

Analysis and assessment of the effects of phase noise in constant envelope multicarrier satellite transmissions

“…The spectral efficiency of CE-SC-FDMA is the same of CE-OFDM, as the DFT pre-coding does not change the global system baud-rate [10].…”

“…The procedure to generate the CE-SC-FDMA signal is the same used for CE-OFDM, i.e. : I-FFT applied to the oversampled zero-padded conjugate-symmetric sequence, phase modulation applied to the real-valued SC-FDMA signal, using the same normalization constant considered for the CE-OFDM [10], and, finally, transmission onto the channel. For sake of clarity and completeness, we report in the equation below the analytical expression of the real-valued SC-FDMA signal:…”

“…As far as the CE-SC-FDMA is concerned, the main difference with respect to the CE-OFDM consists of the DFTbased pre-coding applied to the symbol block of size B≤N transmitted by each user [10]. In particular, the DFT-pre-coded data sequence of user u be denoted by { }…”

“…Frequency domain equalization is obliged for CE-SC-FDMA when transmission over a frequency-selective channel is performed. Phase unwrapping is required in order to avoid phase jumps in the event that received phases cross the π-radian boundary [8] [10]. Decoding and symbol demodulation encompasses the I-DFT decoding when CE-SC-FDMA is considered.…”

“…in [8] and [9] and by Mulinde, Rahman and Sacchi in [10] respectively. In particular, [10] compared the performance of CE-OFDM and CE-SC-FDMA transmitting data over a 2GHz LMS channel affected by Ricean fading and nonlinear distortion due to non-ideal amplification. Both CE-OFDM and CE-SC-FDMA clearly outperformed conventional OFDM and SC-FDMA.…”