Analog Radio-over-Fiber-Aided Optical-Domain MIMO Signal Processing for High-Performance Low-Cost Radio Access Networks

Wireless communication is facing an ever increasing thirst for high-quality data transmission. However, this imposes high demands on the radio access networks (RANs), where optical fiber has been widely used for both the backhaul and fronthaul. However, the explosive escalation of wireless tele-traffic tests the limits of the RAN's revenue vs. cost trade-off, which motivates low-cost designs. Hence, we present a cost-efficient but high-performance radio over fiber (RoF)-aided RAN concept. We commence by introducing this motivation, followed by a brief introduction to analog RoF (A-RoF) and digitized RoF (D-RoF), as well as to wireless multiple-input multiple-output (MIMO) techniques. Then we present the centralized RAN (C-RAN) concept relying on A-RoF-aided MIMO signal processing, where the MIMO signal is carried by fiber and processed optically in a central unit. Subsequently, we focus our attention on a C-RAN small cell application followed by our performance vs. cost analysis of the A-RoF system compared to that of its baseband counterparts, demonstrating that the A-RoF design is capable of reducing the RAN's total cost while meeting the Third Generation Partnership Project's requirements.