LORA: Loss Differentiation Rate Adaptation Scheme for Vehicle-to-Vehicle Safety Communications

The existing study shows that safety applications supported by vehicle-to-vehicle (V2V) communications have the potential to address 80% of all road crash issues. IEEE 802.11p is a key enabling technology to support V2V safety applications. To meet the stringent delay and reliability requirements of these applications, rate adaptation (RA) approaches have been proposed to determine the optimal data transmission rate, according to the channel conditions such as packet losses. However, existing RA solutions cannot be directly applied to V2V safety communications in highway scenarios, which exhibit lots of dynamics and severe packet losses. Moreover, physical (PHY)-layer channel fading and medium-access-control (MAC)-layer interference contribute differently to the packet losses and, thus, should be treated separately. To address these issues, in this paper, we propose a LOss differentiation RA (LORA) scheme. LORA can estimate the average packet loss rate (PLR) for each sender and differentiate the fading losses from the interference losses. Extensive evaluation results demonstrate that LORA can provide reliability guarantees for V2V safety applications, as well as a response to environment changes in a real-time manner.