Measurement and comparison of Sub-1GHz and IEEE 802.11p in vehicular networks

Performance of safety applications of vehicular networks largely depends on the reliability of the communication channel. However the IEEE 802.11p channel is unreliable according to the previous measurement-based work, which reported that the whole communication range is a 'gray-zone' and the packet inter-reception time suffered from blackouts with a relatively high probability. Besides the 5.9 GHz band of the IEEE 802.11p channel, the vehicular networks have also utilized the Sub-1GHz band. Here, we have compared the beaconing performance of the Sub-1GHz channel and the IEEE 802.11p channel simultaneously in field experiments. The comparison is based on the packet delivery ratio (PDR) and the packet inter-reception (PIR) time. Results suggest that the Sub-1GHz channel achieves larger communication range with smaller jitter than that of the IEEE 802.11p channel. Different from previous work, the good-reception (PDR > 90%) zone exists in a considerable range of two channels in our field experiment environments. Moreover, the gain of the antenna can directly impact the good-reception zone.