64/32/16QAM-OFDM using direct-detection for 40G-OFDMA-PON downstream

A 43.6Gb/s downstream OFDMA-PON is demonstrated using optical single-side band 64/32/16QAMOFDM signals and direct-detection receiver through 20km SSMF. Only one photodiode/OFDM receiver is required at the ONU, thereby significantly reducing system implementation complexity and cost.