SI-POF Transmission with OFDM and Sub-carrier Pairwise Coding

Abstract

In this study, data transmission over step-index plastic optical fiber (SI-POF) is demonstrated using orthogonal frequency division multiplexing (OFDM) scheme with sub-carrier pairwise coding (PWC). To investigate the performance of OFDM with PWC, a simulation study is implemented with QPSK and 16-QAM format using the Gaussian theoretical frequency response for a 60 m SI-POF channel. For a data rate of 200 Mbps with QPSK-OFDM, the study shows that compared to equalization, PWC offers about 1.5 dB improvement at a bit-error-rate (BER) of 10−3. An experiment is then set-up with a 60 m SI-POF that uses an eye-safe resonant cavity light emitting diode (RC-LED) as the optical source. The experiment shows that at a bit rate of 200 Mbps with QPSK-OFDM, PWC offers a 1.82 dB improvement in SNR at a BER of 10−3. For the same data rate with 16-QAM-OFDM, PWC offers about 1.1 dB Q2-factor improvement for a modulation index of 0.8. The study therefore shows that PWC improves the BER performance of an SI-POF link that uses OFDM.