*Article* **Nonlinear Distortion by Stimulated Brillouin Scattering in Kramers-Kronig Receiver Based Optical Transmission**

**Yuzhu Zhu 1,2, Jiangbing Du 2,\*, Weihong Shen 2 and Zuyuan He 2**


**\*** Correspondence: dujiangbing@sjtu.edu.cn

**Abstract:** Nonlinear distortion for single-sideband (SSB) signals will significantly reduce the performance of Kramers–Kronig (KK) receiver-based optical transmission. In this work, we present a proof-of-concept study of stimulated Brillouin scattering (SBS)-induced nonlinear distortion for 10 Gbaud and 28 Gbaud SSB QAM16 transmission over 80 km standard single mode fiber (SSMF) based on a KK receiver. Significantly reduced bit error rate (BER) has been experimentally observed due to the SBS and the threshold of SBS at about 7 dBm is detected for such an 80 km SSMF link. With left sideband (LSB) modulation of SSB, together with optical filtering, reduced SBS nonlinear distortion has been achieved with ~2 dB power tolerance improvement. The results reveal an important issue of SBS-induced nonlinear distortion, which would be of grea<sup>t</sup> significance for KK receiver-based optical transmission applications.

**Keywords:** nonlinear distortion; Kramers–Kronig receiver; stimulated Brillouin scattering
