Abstract
The paper proposes a novel adaptive radio-over-fiber (RoF) system for next-generation cloud radio access network (C-RAN), aiming to optimize the operation cost in terms of power consumption while maintaining required data rate. By jointly considering the nonlinear distortion from Mach-Zehnder modulator (MZM) and high power amplifier (HPA) due to high peak-to-average-power ratio (PAPR) in the electronic domain, we first provide a 2×2 multiple-input mulitple-output orthogonal frequency division multiplexing (MIMO-OFDM) baseband model on electrical SNR (ESNR) for a single RoF transmission line. To take the modulation levels into consideration, we provide the optical signal to noise ratio (OSNR) analysis that jointly considers the electrical SNR (ESNR) model and the non-linear effect of the optical transmission. This optical SNR (OSNR) analysis result is further used in the subsequent power consumption model for both the downlink and uplink of the considered RoF transmission system. Case studies via simulation and numerical experiments are conducted to verify that the proposed RoF system not only can reach the lowest power and spectrum consumptions at same time, but also consumes considerably less power than current RoF system.
Highlights
Today’s wireless traffic is dominated by Internet protocol (IP)-based multimedia services and applications, which have caused significant burdens on the radio access networks (RANs)
2.1 Cloud radio access network (C-RAN) Under the current distributed antenna systems (DAS) architecture, each Base station (BS) serves as a layer-2 switch by providing baseband processing functions and is further connected to the remote radio unit (RRUs) via a high-speed link, referred to as front-haul
Due to the highly dynamic environment, the Wavelength division multiplexing (WDM)-based CRAN could waste a significant amount of energy and be subject to low channel utilization on optical transmissions that have to over-provision to meet the stringent quality of service (QoS) and bandwidth requirements
Summary
Today’s wireless traffic is dominated by IP-based multimedia services and applications, which have caused significant burdens on the radio access networks (RANs). 2.1 Cloud radio access network (C-RAN) Under the current distributed antenna systems (DAS) architecture, each BS serves as a layer-2 switch by providing baseband processing functions and is further connected to the remote radio unit (RRUs) via a high-speed link, referred to as front-haul Such a distributed network architecture has been considered short of flexibility and dynamic configurability for fluctuating traffic demand and multiple wireless standards, coverage, and frequency spectrum [6]. Due to the highly dynamic environment, the WDM-based CRAN could waste a significant amount of energy and be subject to low channel utilization on optical transmissions that have to over-provision to meet the stringent QoS and bandwidth requirements Another problem due to the use of digital front-haul link is caused by analogdigital conversion that naturally increases the end-to-end latency and hardware complexity.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
