HybridLQI: Hybrid MultihopLQI for Improving Asymmetric Links in Wireless Sensor Networks

The article proposes HybridLQI to improve the performance of MultihopLQI in the asymmetrical wireless links sensor networks. Every node can maintain the number of messages it sends to each of its neighbours and how many of them are acknowledged, the packet loss percentage over the links can be calculated. Link Quality Indicator (LQI) is used to estimate the downlink channel. Therefore, without adding any extra cost to the network, the bi-directional channel quality can be calculated. Asymmetrical links are created by setting the Base Station transmitting at higher power than the other nodes. This approach in a dense network improves message received percentage by up to 20% for the whole network. For sparse asymmetrical links networks with nodes in straight line and having direct line of sight, this approach improves the packet reception percentage by up to 350% for the node which is 3 hops away from the Base Station. All the results are based on the experiments performed on the real platform.