Scheduling in Densified Networks: Algorithms and Performance

作者:Moharir Sharayu*; Krishnasamy Subhashini*; Shakkottai Sanjay*
来源:IEEE/ACM Transactions on Networking, 2017, 25(1): 164-178.
DOI:10.1109/TNET.2016.2580614

摘要

With increasing data demand, wireless networks are evolving to a hierarchical architecture where coverage is provided by both wide-area base stations (BS) and dense deployments of short-range access nodes (ANs) (e.g., small cells). The dense scale and mobility of users provide new challenges for scheduling: 1) high flux in mobile-to-AN associations, where mobile nodes quickly change associations with ANs (time scale of seconds) due to their small footprint and 2) multi-point connectivity, where mobile nodes are simultaneously connected to several ANs at any time. We study such a densified scenario with multi-channel wireless links (e.g., multi-channel OFDM) between nodes (BS/AN/mobile). We first show that traditional algorithms that forward each packet at most once, either to a single AN or a mobile user, do not have good delay performance. We argue that the fast association dynamics between ANs and mobile users necessitate a multi-point relaying strategy, where multiple ANs have duplicate copies of the data, and coordinate to deliver data to the mobile user. Surprisingly, despite data replication and no coordination between ANs, we show that our algorithm (a distributed scheduler-DIST) can approximately stabilize the system in large-scale instantiations of this setting, and further, performs well from a queue-length/delay perspective (shown via large deviation bounds).

  • 出版日期2017-2