Statistical analysis of the temporal dynamics of coupling in strongly coupled multi-core fibers

With the growing demand for data traffic, new types of optical fiber have been proposed to address the capacity crisis of existing single-mode fiber infrastructure. Space-division multiplexed (SDM) systems promise to exploit multiple spatial channels for parallel data transmission. The aim of this study is to provide a systematic approach to experimentally investigate the fluctuations of random coupling in the temporal domain of coupled multi-core fibers (MCFs). Understanding these temporal dynamics is crucial to setting requirements for digital signal processing and to developing robust signal recovery algorithms. This is also the first step towards dynamic channel models of these fibers. One of the key requirements for untangling the signals after transmission is accurate knowledge of channel behavior in both the time and frequency domains. We present a statistical and experimental analysis of the temporal dynamics of random coupling in strongly coupled MCFs. Based on a statistical time-drift model, we have experimentally characterized the temporal response of coupled MCFs and their statistical properties, such as the temporal autocorrelation function and the probability density function of fractional optical power.