A radio-on-fiber based millimeter-wave road-vehicle communication system for future intelligent transport system-effect of cell size

This paper proposes a radio-on-fiber (ROF) based road-vehicle communication system. In the proposed system, several radio base stations (RBSs) are connected with one control station (CS) by an ROF technology. All RBSs use the same frequency band of millimeter-waves to communicate with mobile stations (MSs). Consequently, one virtual large cellular zone based on the millimeter wave band can be constructed using several RBSs controlled by one CS. Based on the virtual large cellular zone, handover is performed. However, in one virtual cellular zone, interference occurs at the boundaries between adjacent cellular zones by RBSs. To overcome the interference, we use code division multiplexing as a modulation scheme to communicate between MSs and RBSs. The feasibility is confirmed by developing an experimental testbed and performing field trials for the downlink, and we discuss the effect of RBS cell size.