Energy-efficient air-indices for distance queries on road networks

We study the problem of distance queries on a road network under the wireless data broadcast environment. By exploiting special properties of road networks, we design an air-index (indexing scheme on the wireless broadcast model) called the CH Index. Experimental evaluation shows that our CH Index is more energy efficient than previous indices by an order of magnitude. We also extend the CH Index to the CHBN Index which provides a tradeoff between energy efficiency and response time via a user-tunable parameter. It has faster response time than CH while being more energy-efficient than previous methods.