Experimental Demonstration of Delta-sigma Modulation Supported 65536-QAM OFDM Transmission for Fronthaul/WiFi Applications

We demonstrate the digitization and transmission of 65536-QAM OFDM signals over 20-km fiber via 10-Gbaud PAM-4 IM-DD channel. SNR of 57.7dB is achieved for baseband signals with standard PAM-4 and the proposed SNR-improved delta-sigma digitization.