TITLE:
Study on 4PAM Radio over Fiber System Using Self-Mixing Technique
AUTHORS:
Luo Chen, Yufeng Shao, Fuping Chen, Shilu Shen
KEYWORDS:
Optical Communication, 4PAM, RoF, Self-Mixing
JOURNAL NAME:
Optics and Photonics Journal,
Vol.6 No.8B,
August
25,
2016
ABSTRACT:
In this paper, a simplified optical millimeter-wave generated by two optical sidebands beating together in a 60 GHz radio over fiber (RoF) system with 10 Gbit/s 4-pulse amplitude modulation (4 PAM) transmission signal is proposed and simulated. 10 Gbit/s electrical 4 PAM signals modulated are conveyed over the length of 40 km standard single mode fiber (SMF) and recovered via the self-mixing technique after detecting directly at the receiver. Graphs of time-domain wave, frequency-domain and optical spectrum are measured out in different period, and the comparison of error vector magnitude curves of NRZ and 4 PAM signals under the different length of fiber is accomplished. The capacity of 4 PAM modulation is higher, though NRZ performs better than 4 PAM selected in RoF system within 80 km of fiber length as shown in the simulation results.