摘要

In a Wireless sensor network (WSN) with multi-hop communications, nodes close to a sink drain more battery energy than others in relaying packets, which causes lifetime of the WSN to be shortened. To solve the uneven energy expenditure problem, we present a novel cluster-based routing algorithm, called Grid-based routing algorithm with cross-level transmission (GRACT), in which sensing field is divided into grids constituting several levels, a Cluster head (CH) is elected in each grid, and clusters are formed by letting each non-CH node join the closest CH. Under GRACT, a CH is only allowed to delivers its packets to the neighboring level and the cross level with ratios p and 1-p, respectively. Additionally, two Optimization models are presented to prolong lifetime of the WSN. Simulation results show that GRACT can balance the energy consumption among nodes and improve network lifetime.