Antenna selection diversity for IEEE 802.11p

Dependable vehicular communications systems are a key requirement for the implementation of intelligent transportation systems (ITS). Multiple antenna receivers enable the utilization of spatial diversity to increase the reliability as well as improve the availability. The cost of a multiple antenna receiver is the increased hardware complexity due to multiple receive chains. In this paper we demonstrate that antenna selection for IEEE 802.11p allows to connect the antenna with the best instantaneous signal to noise ratio (SNR) to a single receive chain while maintaining the diversity gain. We extend the IEEE 802.11p frame structure by two short preambles to estimate the SNR for each receive branch. The numerical simulation results from our standard compliant link level simulation show a bit error ratio reduction from 8.159 · 10^-3 to 6.681 · 10^-3 at an SNR of 8 dB and from 4.688 · 10^-5 to 1.063 · 10^-5 at an SNR of 12 dB with antenna selection.