Mitigation of Nonlinear Distortions for a 100 Gb/s Radio-Over-Fiber-Based WDM Network

Abstract

Next-generation cloud radio access networks (C-RANs) are anticipated to provide multi-Gbps data rate transmission and ultra-high bandwidth capacity, which is one of the key performance indicators for future mobile networks. The integral layout of fiber optics and radio network manages the capabilities of the C-RAN, but needs to be optimized in terms of cost, reliability and further scalibility. For C-RAN architectures, Radio over Fiber (RoF) transport-based fronthaul is a promising candidate but the associated issues of distortions due to nonlinear impairments (NLIs) from power amplifier, linear distortions (LDs) due to modulating lasers and high peak to average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals need to be addressed. This work investigates these performance limiting factors and presents a DSP receiver-based solution to mitigate the effects of NLIs, LDs and high PAPR. Simulations are performed by applying a various range of transmission input powers, different quadrature amplitude modulation (QAM) formats for the OFDM signal, optimized filtering at the receiver end and varying channel spacing among the optical WDM channels to analyze the performance of the proposed receiver under different conditions. The simulations and theoretical model of the proposed case studies verify that the presented solution for the RoF transport utilize less power, performs better for longer transmission distances, supports higher modulation formats and transports large number of WDM channels in the presence of NLIs and DLs as compared to the conventional RoF approach. With compensation of NLIs and LDs, transmission distance up to 10 km is investigated using 16 WDM channels with aggregate data rate of 100 Gb/s which shows that the proposed receiver can be used for future C-RAN fronthaul networks.

Characteristics Analysis of Hybrid Optical Amplifier with Doped Fiber Variations for Fiber Optic Communications Network

“…The last part is the receiver, which consists of a Positive-Intrinsic-Negative (PIN) detector to detect and convert incoming optical signals into electrical signals. The PIN detector can detect various wavelengths [25] from 3R (reshaped, re-timed, and re-amplified) generators that amplify optical signals over long distances [26]. Then, the data received by the 3R is forwarded to the Bit Error Rate (BER) analyzer, which measures the bit error rate in digital communication systems [27].…”

Analyzing the BER and optical fiber length performances in OFDM RoF links

“…A dual-drive type of LiNb-MZM is used. The controlling of each MZM can be done with positive and negative signals of the components of I or Q baseband OFDM modulating signal at the two MZM inputs [27]. Each MZM output signal is then combined by the optical power converter to procedure CO-OFDM Here, an EDFA amplifier can be connected as a booster amplifier for compensating the losses acquired in the transmitter besides enhancing the signal in the fiber optics channel as shown in Figure 6.…”

Opto-Electronic Oscillators for Micro- and Millimeter Wave Signal Generation

“…The centralized oscillator signal was distributed to the base stations without the need for electro-optical and opto-electronic conversion. Radio over fiber [94][95][96] is proposed as an efficient and sophisticated solution to distribute the centralized OEO signal. The idea is shown in Figure 10.…”