With the rapid evolution of WSNs technology,it is very important to evaluate link quality quickly and accurately,so that the routing protocols can take relevant strategies in time to keep the entire network working steadily and efficiently. However,the issue of improving link quality assessment methods on physical layer is still open to research. To tackle this issue,a novel link quality assessment metric called S 3 LQA is proposed,which estimates the link quality of wireless sensor networks by CC2420 wireless radio frequency transceiver principles and free space propagation theory. The metric adopts both complete and incomplete packages to improve the evaluation performance effectively based on IEEE802. 15. 4 frame format and DSSS-O-QPSK mechanism. The experimental results show that the proposed method can improve energy cost and achieves better real-timing performance than traditional counting-based ( PRR) link quality assessment metric.
