Improving Drive-Thru Access to Roadside Infrastructure by Lightweight Relay

In this paper we propose a relay-based solution to extend the service range of roadside APs. When a vehicle moves towards the AP, its signal quality to the AP may be poor. At this time, it uses a relay vehicle ahead of it which has good signal quality, to relay the data. When the vehicle is moving away from the AP, it uses a relay node behind it to set up a backward relay path to keep the connection. Different from existing relay based work (Zhu, 2005), our solution can deal with high vehicle mobility, and let drive-thru vehicles maintain high throughput in the extended AP coverage area.