Frequency sharing scheduling with OFDMA for road to vehicle and inter-vehicle communications

In this paper, frequency sharing with OFDMA (orthogonal frequency division multiple access) is considered to be applied to road to vehicle communication (RVC) and inter-vehicle communication (IVC). However, it is difficult to accomplish perfect frequency and timing synchronization in the autonomous distributed system such as IVC. This will result in multiple access interference with the collapse of orthogonality among OFDMA subcarriers due to carrier frequency and timing offsets of IVC. This paper proposes a frequency sharing scheduling to suppress the interference to RVC by selecting subcarriers and controlling power properly during the period allocating the time slots and the subcarriers of OFDMA to multiple pairs of IVC and RVC, respectively. Furthermore, the proposed scheduling can give the appropriate priority to the short distance IVC pair from the frequencies unutilized by RVC.