Design and Performance Analysis of A MAC Protocol for Wireless Public Bus Networks

Providing high quality Internet service in public buses allows bus passengers to entertain themselves and even to work remotely during their travel time, thus significantly improving their quality of life. In this paper, a MAC protocol for public bus networks, called BusMAC, is proposed to provide high quality Internet service for bus passengers. The proposed protocol decreases collisions caused by multiple access from multiple passengers based on the improved bus network architecture. The MAC protocol based on super-frame structure decreases greatly the communication bottleneck in the bus network, combined with dynamical contention and piggyback mechanisms. The performance analysis of BusMAC is carried out based on request contention model and data scheduling model. Each model is expressed as a two-layer structure which catches up two access phases in the proposed MAC protocol. Extensive simulations are conducted to evaluate the BusMAC protocol. With simulations, the performance analytical models are verified to be accurate. Also, the results show that BusMAC can achieve much better performance than the traditional ones, and is more adaptive to bus communication. Specially, the deployment feasibility in the realistic system for the protocol can be accounted for through the experiments conducted under realistic mobility trace scenarios.