one of the main challenges in wireless sensor network is energy problem and life cycle of nodes in networks. several methods can be used for increasing life cycle of nodes. one of these methods is load balancing in nodes while transmitting data from source to destination. directed diffusion algorithm is one of declared methods in wireless sensor networks which is data-oriented algorithm. direct...

This paper deals with the distance estimation issue in 802.15.4 wireless sensor networks. On a basis of signal strength of received frames a distance between two sensor nodes is estimated. Estimation is done by using the log-normal shadowing radio propagation model (LNSM). Basic problems of signal strength based systems are variation of RSSI parameter and correct calibration of coefficients for...