We study the problem of energy-balanced data propagation
in wireless sensor networks. The energy balance property
guarantees that the average per sensor energy dissipation
is the same for all sensors in the network, during
the entire execution of the data propagation protocol. This
property is important since it prolongs the network˘s lifetime
by avoiding early energy depletion of sensors.
We propose a new algorithm that in each step decides
whether to propagate data one-hop towards the final destination
(the sink), or to send data directly to the sink. This
randomized choice balances the (cheap) one-hop transimssions
with the direct transimissions to the sink, which are
more expensive but “bypass” the sensors lying close to the
sink. Note that, in most protocols, these close to the sink
sensors tend to be overused and die out early.
By a detailed analysis we precisely estimate the probabilities
for each propagation choice in order to guarantee
energy balance. The needed estimation can easily be performed
by current sensors using simple to obtain information.
Under some assumptions, we also derive a closed form
for these probabilities.
The fact (shown by our analysis) that direct (expensive)
transmissions to the sink are needed only rarely, shows that
our protocol, besides energy-balanced, is also energy efficient.