  One of the most important issues in Wireless Sensor Networks (WSNs) is severe
energy restrictions. As the performance of Sensor Networks is strongly
dependence to the network lifetime, researchers seek a way to use node energy
supply effectively and increasing network lifetime. As a consequence, it is
crucial to use routing algorithms result in decrease energy consumption and
better bandwidth utilization. The purpose of this paper is to increase Wireless
Sensor Networks lifetime using LEACH-algorithm. So before clustering Network
environment, it is divided into two virtual layers (using distance between
sensor nodes and base station) and then regarding to sensors position in each
of two layers, residual energy of sensor and distance from base station is used
in clustering. In this article, we compare proposed algorithm with well-known
LEACH and ELEACH algorithms in homogeneous environment (with equal energy for
all sensors) and heterogeneous one (energy of half of sensors get doubled),
also for static and dynamic situation of base station. Results show that our
proposed algorithm delivers improved performance.
