Consecutive radio-zone DSRC system with an in-vehicle reactance diversity antenna

A high-speed wireless link for traveling vehicles would surely be required in the near future. We developed a consecutive radio zone DSRC (dedicated short range communication) system with in-vehicle antenna using a new angle diversity technique to provide this sort of high-speed wireless link. In the consecutive radio zones, the same radio signals with the same frequency are distributed by radio-on-fiber technology. To mitigate the interference of coherent waves in adjacent areas, we designed a new in-vehicle antenna based on the reactance diversity scheme. The reactance diversity antenna works as a diversity antenna in a stand-alone form, and is able to improve anti-fading performance without having to change the existing DSRC receiver design. Our experimental results demonstrate that consecutive radio zones can successfully extend the service area while maintaining the quality of π/4 shift QPSK modulated communication defined by the Japanese DSRC standard. Our experiments show that the convenience of a DSRC system can be further enhanced in a reasonable manner, thus enabling Internet ITS to become more realistic.