Towards Video Packets Store-Carry-and-Forward Scheduling in Maritime Wideband Communication

摘要

In this paper, we investigate uploading monitoring videos for vessels via a maritime wideband communication network. The Worldwide Interoperability for Microwave Access (WiMAX) technology is utilized to establish a shore-side network infrastructure, and a packet store-carry-and-forward routing mechanism is implemented to address the intermittent network connectivity in maritime communications. A resource allocation problem is formulated to maximize the weights of uploaded video packets, subject to the intermittent network connections and the release time and deadline of each video packet. Time-capacity mapping is applied to transform the original resource allocation problem to a two-machine non-preemptive scheduling problem. As ship routes are relatively stable, the global information in terms of release time, deadline and other time indices of video packets, as well as the schedules of vessels is known a priori. We propose two offline scheduling algorithms, namely Time-capacity mapping based two phase (TMTP) algorithm, and Interval graph theory based job relay selection (IGTJRS) algorithm. Both algorithms achieve a time complexity of O(n~2). The performance of proposed algorithms is evaluated through simulation based on actual ship route traces obtained from dedicated Navigation software BLM-Ship.