Abstract:
The demand from users for high-quality services like video gaming, video conferencing,
and multimedia services increases from year to year. But it requires high bandwidth to
access those services. 5G is one of the promising technologies that provides larger bandwidth for all those requirements, but the wireless range is limited by rain attenuation,
atmospheric absorption, and propagation loss. Due to this, radio over fiber (RoF) system
is proposed and the best choice to answer all the above problems. This system combines
the optical network with the wireless network for future broadband applications, which provides a larger bandwidth, low latency, high data rate transmission, low attenuation, high
immunity to elector-magnetic interference, and low power consumption. However, the
performance of the RoF system is mostly affected by the chromatic dispersion and attenuation of high-bit-rate long-distance communication. These factors lead to inter-symbol
interference and, ultimately, a high bit error rate (BER), a low Q factor value, a limited
transmission distance, a low received power, and a decreased capacity. Dispersion compensation fiber (DCF), Fiber Bragg Grating (FBG), and Erbium Doped Fiber Amplifier
(EDFA) are commonly used in the RoF system to alleviate this problem.
In this thesis, a hybrid DCF+CFBG dispersion mitigation technique and a hybrid Raman+EDFA optical amplifier for the Wavelength Division Multiplexing (WDM)-RoF system is used to minimize the effects of dispersion and attenuation, respectively. The hybrid
Raman+EDFA outperforms EDFA and Raman in terms of Q factor and Min.BER for
fiber lengths ranging from 60 to 180 km, having a 2.41, 0, and 0-dB Q factor at 180 km
and 0.00567285, 1, and 1 BER at 180 km, respectively. The hybrid DCF+CFBG achieves
a high Q factor and Min.BER of 6.49 dB and 2.72E-11, respectively, but its OSNR and
received power performance are lower than CFBG, which are 13.175 dB and -6.37 dBm,
respectively, whereas CFBG achieves 27.95 dB and 6.56 dBm, respectively, and both are
evaluated at 180 km fiber length and 10 dBm input power.
Keywords: CFBG, DCF, RoF, OSNR, WDM and BER.