To prolong system lifetime is a major challenge in wireless sensor networks

a novel congestion-sensitive routing algorithm is proposed.The proposed algorithm fully considers the relationship between the data load the buffer levels of neighboring nodes

and the local channel occupancy.Every node calculates a weight to describe its local congestion status.The nodes select the downstream node with the greatest weight as next hop so that the energy consumption and load of downstream nodes are balanced.At the same time

the probability of congestion is reduced.The simulation results show that the proposed algorithm effectively reduces the packet drop rate and average network delay

and thus extends the network lifetime.