Radio energy dissipation model. In this work, the energy
model for the sensors is based on the first-order radio model
as used in Heinzelman (2000). In this model, a radio dissipates
Eelec=50 nJ/bit to run the transmitter or receiver circuitry
and eamp=100 pJ/bit/m2 for the transmitter amplifier.
The radio can control the transmission power to use only the
necessary energy to reach the intended node. In our simulations,
we used a packet length k of 2000 bits. To transmit a
message to a distance of d(Etx(k,d) and to receive a message
of k bits (Erx(k)), the radio expends energy, which is shown in
the following: