The modulation principles of the two different single-sideband signals based on independent dual-driving Mach-Zehnder modulator (DDMZM) and the in-phase/quadrature modulator are introduced theoretically. Based on the study of 100 Gbit/s 16-quadrature amplitude modulated single-sideband signal after 75-km standard single-mode fiber transmission, we analyze the principles of parameter optimization of the two approaches. The Kramers-Kronig (KK) algorithm is used to recover the single-sideband signal and eliminate the signal-to-signal beating interference (SSBI) at the receiving end. The results show that, due to effects of the modulator nonlinearity and the carrier signal power ratio, the KK receiver based virtual carrier approach can reduce the received optical power by about 2.3 dB compared with the DDMZM approach at the 7% hard-decision forward error correction threshold with bit error rate of 3.8×10 -3.