Field measurement on simple vehicle-mounted antenna system using a geostationary satellite

This paper presents a field measurement of a simple antenna system mounted on a vehicle by utilizing a geostationary test satellite called Engineering Test Satellite VIII (ETS-VIII). Our developed antenna system is compact, lightweight, and promising for low-cost production. The antenna system is constructed by a 16-cm patch array antenna, which has simple satellite tracking that is controlled by a control unit as the vehicle's bearing is updated from a navigation system in real time. A Global Positioning System (GPS) module is utilized for the navigation system to provide accurate information of the vehicle's position and bearing during traveling. A control unit is provided as antenna-beam control and measured-data acquisition. We thoroughly examine the developed system in field measurements under open field areas and blockage areas in order to evaluate the propagation characteristics caused by utility poles, pedestrian overpasses, and vegetation-covered roads. In this measurement, the received signal power and the average bit error rate (BER) are simultaneously retrieved. Steadily received levels and average BER are satisfactorily attained during satellite tracking in open field areas. Moreover, the fade characteristics and average BER performance are also investigated during signal blockage. The results show that different environments give different degrees of attenuation, which affects the BER performance in terms of fade depth. Ultimately, our proposed antenna system can contribute to the design of future cost-effective mobile satellite communications.