Enhanced Collision Avoidance for Distributed LTE Vehicle to Vehicle Broadcast Communications

In this letter, we investigate the distributed autonomous resource selection for LTE vehicle to vehicle (V2V) broadcast. The effectiveness of collision avoidance and location based resource allocation enhancements is examined. It is found that collision avoidance with multiple data resources reservation per schedule assignment (SA) is a key to improve broadcast reliability. However, in the existing collision avoidance algorithm reserving multiple resources per SA can lead to many data packet collisions if a SA collision happens. We propose an enhanced collision avoidance to address this issue. The idea is to use selected data packets to disseminate the reservation of data resources and SA resources, which can provide better communication among neighbor vehicles on resource reservation and reduce data collisions. Simulation results show that the proposed collision avoidance enhancement can effectively improve SA and data transmission reliability. The network capacity in terms of supported vehicles under given V2V service requirements is largely increased by 17% at a negligible cost of added overhead.