Subcarrier Multiplexing RF Plans for Analog Radio Over Fiber in Heterogeneous Networks

Abstract

Analogue Radio over Fibre together with subcarrier multiplexing and wavelength division multiplexing is proven to be more cost-efficient when compared to CPRI fronthaul solutions. Furthermore, the results of the allocation of RF channels to better exploit the available modulation bandwidth of commercial transceivers show that the uniformly spaced channel plan is bandwidth efficient but susceptible to interference. The ITU-T G.692 plan results in much higher tolerance to interference but it is more bandwidth consuming. Finally, the proposed 'mind the gap' RF channel plan shows an acceptable compromise between bandwidth consumption and robustness against intermodulation interference.

Availability and Fade Margin Calculations for 5G Microwave and Millimeter-Wave Anyhaul Links

“…Twisted pair or coaxial cables are limited in the bandwidth distance product; therefore, metallic cables were step-by-step replaced by optical fibers. Lightweight optical fibers are already widely used for remote antenna heads as feeder lines, and there is a significant research activity of radio-over-fiber (RoF) systems to deliver combined "fiber/wireless" networks for a reduced cost, with easier installation to support 5G deployments [5,[17][18][19][20][21][22][23]. As an example, the µ/mmW links of an urban access network are shown (dark lines) in Figure 3, as seen in the link planning tool.…”

“…Due to low latency requirements, cloudification, and 5G slicing, the cloud core networks tend to be more distributed toward the edge sites. Current distributed radio access networks tend to be more centralized, and the role of fiber optics in cloud RANs (radio access networks) is increasing [17][18][19][20][21][22][23]. However, the microwave and millimeter-wave links still continue to form an essential portion of the mobile anyhaul [1,3,4,6,7,9].…”

Total Cost of Ownership of Digital vs. Analog Radio-Over-Fiber Architectures for 5G Fronthauling

“…In the second case, the modulation uses an intermediate frequency (IF). Figure 1b depicts an IF-A-RoF solution, where subcarriers are (de-)aggregated by using frequency division multiplexing (FDM) via analog signal processing that includes frequency down-/up-conversions and IF combining/splitting [29]. In the third case, the radio signal is processed digitally by a DSP module before being modulated on an optical or millimeter-wave (mmWave) carrier [17].…”

Comparison of Optical Transport Technologies for Centralized Radio Access Network Using Optical Ground Wire

“…This also simplifies the optical wavelength channel allocation scheme. Furthermore, SCM also contributes to the simplification of RRHs by reducing the number of optical components, although we still require electrical mixers and local oscillators in the RRHs [34], [35].…”