Fiber Bragg Grating (FBG) With Post-Dispersion Compensation Scheme to Eliminate Dispersion Power Fading in Radio over Fiber (RoF) Systems

Chromatic dispersion in Radio over Fiber (RoF) systems causes power fluctuations in the Radio Frequency (RF) signal generated by the photodetector (PD) known as dispersion power fading (DPF). In this article, DPF is overcome by compensating chromatic dispersion using a Fiber Bragg Grating (FBG) placed after the fiber channel. In order for the FBG to overcome DPF well, the dispersion value of the FBG must be adjusted to the length of the fiber used. For RoF systems with an optical wavelength of 1550 nm, the dispersion value of the FBG is equal to the fiber length multiplied by negative 16.75 ps/nm. System performance testing in this article is done by simulation using OptiSystem software. The simulation results show that in the RoF system with an input of 60 GHz RF signal, there is a very large RF signal power drop at fiber lengths of 1, and 3.1 km. In the RoF system equipped with FBG placed after the fiber channel, the received RF signal power tends to be stable and there is no longer a large power drop as in the standard RoF system.