We developed Millimeter-wave high speed spot communication system using radio-over-fiber technology for ITS telecommunication use. This system has wide bandwidth and provides a high-capacity channel between the base station and parked vehicles. The installation conditions (height, elevation angle) of the base station antenna of this system that enabled the largest possible communication area were obtained by simulation. In addition, we measured propagation and transmission characteristics. The width of the error-free service area was 8 m, which enables three vehicles to be served in one service area.

Mobile computing networks make it possible to offer information access to mobile users. In order to transfer data over mobile networks efficiently, appropriate data transmission control methods for mobile terminals must be established. This paper focuses on spot communication systems to transmit data at high speeds between base stations and mobile terminals. It proposes a flexible and efficient data transmission method that is suitable for spot communication systems. The proposed method transfers subsets of the data to the base stations that are best sited relative to the mobile terminal. This helps to reduce the traffic load of the network significantly. Simulation results confirm the validity of the proposed method. Furthermore, the data receiving time of the mobile terminal, which is an important measure in evaluating the Quality of Service (QoS) for data transmission is analyzed. The result shows that the traffic load in the network is reduced significantly while the QoS is well maintained.