Experimental validation of a constant-envelope OFDM system for optical direct-detection

• Optical communications.
• Optical OFDM systems.
• System performance.
• Nonlinear effects mitigation.

In this paper, we experimentally investigate a peak-to-average power ratio (PAPR) reduction technique based on a constant envelope orthogonal frequency division multiplexing (CE-OFDM) approach in direct-detection optical OFDM (DDO-OFDM) systems. In comparison to conventional DDO-OFDM, our results show a 6.37 dB performance gain in terms of error vector magnitude (EVM) with a 5 Gb/s DDO-CE-OFDM transmission system over 40 km of uncompensated standard single-mode fiber (SSMF) at an optical injection power of 5 dBm.