A microwave photonic filter(MPF)with reconfigurability and tunability resulting from the superposition of the transfer functions is proposed.Based on the Vernier efect between the optical frequency combs and the periodic optical filters,each comb line can be mapped into a sub-filter in the electronic field.The sub-filters are superposed to obtain the total transfer function of the MPF.By manipulating a few comb lines,we can reconfigure the passband shape,tune the bandwidth,and adjust the center frequency independently.Experiments verify that the bandwidth can be tuned from 224.8 to 674.3 MHz,and that the center frequency ranges from 1 to 4 GHz.
This paper presents the fundamental principles and recent advances in the field of linearity enhancement of Mach–Zehnder modulators in microwave photonic systems using all-optical signal processing.A review of the fundamentals and applications that implement the linearity improvement is also provided.
