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Takens' theorem demonstrates that in the absence of noise a multidimensional state space can be reconstructed from a scalar time series. This theorem gives little guidance, however, about practical considerations for reconstructing a good state space. We extend Takens' treatment, applying statistical methods to incorporate the effects of observational noise(More)
The development of protocols to advance the state of the art in Underwater Acoustic Networks (UANs) relies on the use of computer simulations to analyze protocol performance. It is typical for designers to abstract away much of the detail of the physical environment in order to simplify the development of the simulation and ensure the simulation runtime(More)
Acoustic communications provide a viable means for underwater networking. However, extreme propagation delays, limited bandwidth, and half duplex communications, with its inherent use of delay inducing collision avoidance media access and " stop-and-wait " flow control, severely limit the throughput and power of such networks. While full duplex(More)
—Multipath fading, severe bandwidth limitation , non-Gaussian noise, and large propagation delays combine to make an underwater acoustic network (UAN) one of the more challenging ad hoc networking environments. It is important to refine the traditional networking protocols to optimize their performance for the given physical layer constraints of UANs [5].(More)
This paper investigates the fundamental performance limits of medium access control (MAC) protocols for particular multihop, RF-based wireless sensor networks and underwater sensor networks. A key aspect of this study is the modeling of a fair-access criterion that requires sensors to have an equal rate of underwater frame delivery to the base station.(More)
—This paper investigates fundamental performance limits of medium access control (MAC) protocols for multi-hop sensor networks. A unique aspect of this study is the modeling of a fair-access criterion requiring that sensors have an equal rate of frame delivery to the base station. Tight upper bounds on network utilization and tight lower bounds on minimum(More)
Media Access Control (MAC) must be carefully considered in multi-hop Underwater Acoustic Sensor Networks (UASNs) due to limited bandwidth and large propagation delay. In particular, variable propagation delays in UASNs cause inaccurate time synchronization and therefore make reservation-based protocols less favorable. Large propagation delays limit the(More)