Integrated Single Sideband Modulation Based on Sideband Amplification Injection Locking Effect

Abstract

An integrated single sideband (SSB) modulation method for radio-over-fiber (ROF) link, which is based on an integrated multi-section mutual injection (IMSMI) DFB laser benefitting from the sideband amplification injection locking (SAIL) effect, is proposed and experimentally demonstrated. To our knowledge, this is the first time to realize integrated direct-modulation SSB modulation based on SAIL effect. The IMSMI-DFB laser, which overcomes the drawbacks of using discrete devices, simplifies the whole structure. The SAIL effect, which is regulated by the input RF power and bias current of IMSMI-DFB laser, promises a good pathway for adjusting and controlling the modulation frequency, optical carrier to sideband ratio (OCSR) and sideband suppression ratio (SSR). The OCSR of SSB can be optimized to 0 dB and the SSR is over 26 dB from 16 GHz to 26 GHz for this proposed integrated SSB method. The ROF transmission experiments demonstrate that the power fading introduced by fiber dispersion is dramatically eliminated, and the error vector magnitudes (EVMs) of the received 20 MSymbol/s 32 QAM signals at frequencies of 19.571 GHz after 50 km fiber transmission is about 3.88%. This work provides an effective way to realizing integrated direct SSB modulation for ROF link.