MATS: multichannel time-spread scheduling in mobile ad hoc networks

Wireless mobile ad hoc networks (MANETs) have received considerable attention in the last few years. Most research works focus on single-channel MANETs with a single power-level in order to simplify the network design and analysis. How to take advantage of multiple channels and multiple power levels in MANETs poses a serious challenging problem. Recently, a few multichannel transmission protocols such as collision-avoidance transmission scheduling (CATS) have been proposed to harvest the advantage of high transmission efficiency when multiple channels are deployed. Although such protocols do provide ways to coordinate the use of multiple channels, there exist some serious problems such as the throughput fast drop-off under heavy traffic loads. In this paper, we propose a new protocol, namely, multichannel time-spread scheduling (MATS), which attempts to tackle these problems. In MATS, nodes with transmission requests are divided into three groups, which carry out channel reservations in parallel and can simultaneously support unicasting, multicasting and broadcasting at the link level. MATS ensures successful and collision-free data transmissions using the reserved channels and allows multicasting and broadcasting high priorities over unicasting. Both theoretical analysis and extensive simulation studies are carried out which show that the performance of MATS under high traffic loads significantly outperforms the existing schemes.