Leveraging the Near–Far Effect for Improved Spatial-Reuse Scheduling in Underwater Acoustic Networks

We present a spatial reuse resource allocation
scheme for underwater acoustic networks that organizes communications
so as to avoid destructive collisions. One prime source
of collisions in underwater acoustic networks is the so called
near–far effect, where a node located farther from the receiver
is jammed by a closer node. While common practice considers
such a situation a challenge, in this paper we consider it a
resource, and use it to increase the network throughput of spatialreuse
time-division multiple access. Our algorithm serves two
types of communications: 1) contention-free and 2) opportunistic.
Our objective is to maximize the time slot allocation, while
guaranteeing a minimum per-node packet transmission rate. The
result is an increase in the number of contention-free packets
received, and a decrease in the scheduling delay of opportunistic
packets. Numerical results show that, at a slight cost in terms of
fairness, our scheduling solutions achieve higher throughput and
lower transmission delay than benchmark spatial-reuse scheduling
protocols. These results are verified in a field experiment
conducted in the Garda Lake, Italy, where we demonstrated
our solution using off-the-shelf acoustic modems. To allow the
reproducibility of our results, we publish the implementation of
our proposed algorithm.


Roee Diamant, Paolo Casari, Filippo Campagnaro and Michele Zorzi

Published On:

IEEE Transactions on Wireless Communications

Publication Year: