TheMulti-Channel Flow-Aware Medium Access Control Protocol

摘要: The Multi-Channel Flow-Aware Medium Access Control Protocol for Wireless Sensor Networks Eric B. Decker ∗ Email: cire@soe.ucsc.edu Venkatesh Rajendran venkat@soe.ucsc.edu Engineering Department 1156 High Street UC Santa Cruz, CA 95064. Computer Abstract—We introduce the protocol, or (MFLAMA), an energy- efficient, schedule-based, multi-channel medium-access control (MAC) protocol designed data gathering applications in wire- less sensor networks. MFLAMA improves channel utiliza- tion by establishing collision-free transmission schedules across multiple channels. Energy efficiency is achieved preventing packet collisions, idle listening, and transmissions to a node that not ready receive packets. We evaluate through extensive simulations quantify improvement utilization use of Our results indicate as we increase number orthogonal channels used communication, there significant queueing delay. However, notice “diminishing returns” effect channels, i.e., performance improvements observed decrease with beyond certain threshold. This threshold depends on topology traffic flow patterns being used. I. I NTRODUCTION networks have emerged ideal solution scientific societal relevance. Such include environmental monitor- ing, disaster recovery, emergency rescue, tracking mobile objects, etc. typically refer collection low-cost, small nodes processing, (wireless) sensing capabilities. Commercial network radios [1] often support mul- tiple communication As shown Fig- ure 1, can be improved scheduling trans- missions particular example illustrates application, which sink col- lecting from all sensors using forwarding tree. For given pattern, only one flows scheduled without hidden-terminal collisions single channel. three (i.e., F d, e, f ) concurrently collisions. work has been partially supported U.S. Army Research Office under grant W911NF-05-1-0246, Baskin Chair Engineering, NSF grants ANI 0322441 CNS 0534129, Wionics Inc. views conclusions contained this document are those authors should interpreted representing official policies, either expressed implied, Government. Katia Obraczka J. Garcia-Luna-Aceves ∗† katia@cse.ucsc.edu Alto Center 3333 Coyote Hill Road Palo Alto, 94304. jj@cse.ucsc.edu † Fig. 1. Multi-channel applications. In our previous established importance application-aware medium access [2]. paper, FLow-Aware MFLAMA, schedule- based MAC leverages both predictabil- ity some also availabil- characterizes directed [2] uses distributed schedul- ing algorithm establish main features described detail Section III, are: (a) distributed, energy-efficient, collision- free two-hop neighborhood information implicit (b) low delays limited processing storage requirements, (c) robust operation accommodates changes. exten- sive simulations. IV presents simulation benefits scheduling. observe thresh- old. II. R ELATED W ORK Existing protocols categorized contention- , schedule-, reservation-based. PAMAS [3] earliest contention-based proposals address power