Sub-band-based transmission for mode-multiplexed optical systems

Abstract

Mode-multiplexed optical transmission is subject to mode coupling and potentially large differential mode delays. In most recent implementations, these effects are compensated for at the receiver by complex adaptive MIMO equalizers. Although frequency-domain MIMO equalization requires a moderate complexity compared to time-domain equalization, the long required FFTs may face implementation issues and yield a relatively slow response to dynamic effects. In this paper, we evaluate an alternate transceiver architecture based on sub-band partitioning, implemented by filter banks, which enables concurrent time-domain equalization. The performance of sub-band and single-carrier schemes are compared using Monte-Carlo simulations.