Joint Modulation Format Identification and Mode Coupling Estimation Scheme Based on ADTP and MT-CNN for Mode Division Multiplexed Systems

We propose a direct detection scheme based on the asynchronous delay-tap plot (ADTP) and multi-task convolutional neural network (MT-CNN), which realizes the joint monitoring of modulation formats (MFs) and mode couplings (MCs) at the intermediate nodes for mode division multiplexing (MDM) systems. The validity of this scheme is verified through the simulation system with six kinds of popular MFs, several MC intensities and five different spatial modes. The monitoring accuracies of MFs and MCs are more than 98.5% and 98.8%, respectively, and the estimated average root mean square errors (RMSE) of different MCs for five spatial modes are less than 6.3 × 10
^-3
.