Title :
Performance-Enhanced Direct Detection Optical OFDM Transmission With CAZAC Equalization
Author :
Zhenhua Feng ; Ming Tang ; Songnian Fu ; Lei Deng ; Qiong Wu ; Rui Lin ; Ruoxu Wang ; Ping Shum ; Deming Liu
Author_Institution :
Sch. of Opt. & Electron. Inf., Huazhong Univ. of Sci. & Technol., Wuhan, China
Abstract :
Direct detection optical orthogonal frequency division multiplexing (DDO-OFDM) transmission with constant amplitude zero autocorrelation (CAZAC) sequence equalization is proposed and experimentally demonstrated. Simulation results show that more than 2-dB peak-to-average power ratio (PAPR) reduction can be realized using CAZAC equalization, and 50-km standard single mode fiber (SSMF) transmission of 4.11-Gb/s QPSK-OFDM can be achieved with bit-error rate (BER) under forward error correction limit. Transmission performance of QPSK-based DDO-OFDM system is analyzed in both OB2B configuration and fiber link with and without CAZAC equalization. More than 2.5-dB optical receiver sensitivity improvements can be obtained thanks to the PAPR reduction enjoyed by CAZAC equalization. Signal-to-noise ratio for every subcarrier derived from error vector magnitude is estimated and its flatness is confirmed to be much improved with CAZAC equalization. The performance improvements brought by CAZAC equalization can be extended to other modulation formats, and 8.22-Gb/s 16-quadratic-amplitude modulation-OFDM signals transmission using CAZAC equalization is demonstrated with over 1.5 dB enhancement in receiver sensitivity.
Keywords :
OFDM modulation; error statistics; forward error correction; optical fibre communication; optical links; optical receivers; quadrature amplitude modulation; quadrature phase shift keying; 16-quadratic-amplitude modulation-OFDM signals transmission; BER; CAZAC equalization; DDO-OFDM system; OB2B configuration; PAPR; QPSK-OFDM; SSMF; bit error rate; bit rate 4.11 Gbit/s; bit rate 8.22 Gbit/s; constant amplitude zero autocorrelation sequence equalization; distance 50 km; error vector magnitude; fiber link; forward error correction limit; optical receiver sensitivity; orthogonal frequency division multiplexing; peak-to-average power ratio reduction; performance-enhanced direct detection optical OFDM transmission; quadrature phase shift keying; standard single mode fiber transmission; Optical fiber communication; Optical fibers; Optical receivers; Optical sensors; Peak to average power ratio; CAZAC equalization; Direct detection OFDM (DD-OFDM); PAPR reduction; error vector magnitude (EVM);
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2015.2426954
