NoPSM A Concurrent MAC Protocol over Low Low-Data-Rate Rate Low-Power Low Wireless Channel without PRR PRR-SINR Model
Abstract: Concurrent MAC protocols can improve channel usage of wireless sensor networks (WSNs), and provide a high high-performance performance infrastructure for data intensive applications. Most of the existing concurrent MAC protocols are based on proactively constructed physica physicall interference models, i.e., PRR-SINR PRR models (PSM). However, it incurs relatively high bandwidth and energy overheads to construct PSM for WSNs. In this paper, we propose NoPSM, which does not take PSM as base to determine transmission concurrency. Instead Instead,, the base of NoPSM is reactively constructed interference relationships by passively analyzing overlapping relationships among time logs of block data transmissions and corresponding reception status of each packet in blocks. In this way, NoPSM has two salient lient features. First, NoPSM is able to construct interference relationships among nodes quickly and accurately along with block data transmissions without needs of network downtime. Second, based on the constructed interference relationships, NoPSM can ma make ke decisions of transmission concurrency with a comprehensive criterion, which not only estimates quality of any active links after initiating a new link, but also estimates throughput improvement gained from concurrent transmissions. NoPSM has been implem implemented ented in Tinyos-2.1 Tinyos and extensively evaluated in TOSSIM. Experimental results show that NoPSM improves system throughput by up to 60 percent compared with a traditional