Analysis of modulator-induced higher-order harmonics influence on flat and stable optical comb generation based on re-circulating frequency shifter for all-optical OFDM

摘要

The influence of higher-order harmonics produced in modulator on flat and stable optical comb generation based on recirculating frequency shifter (RFS) for all-optical OFDM is analyzed and demonstrated in this paper. We also theoretically analyze the condition for flatness of the optical frequency comb. The resulting theoretical analysis is confirmed by a 16 comb lines and 12.5 GHz spacing RFS generation system. The results demonstrate that flat and stable optical comb generation based on RFS can be a useful solution for multi-wavelength source in all-optical OFDM.