QUICK SWITCH METHOD AND SYSTEM IN WIRELESS SENSOR NETWORK

摘要

A quick switch method based on Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) in a wireless sensor network is disclosed in the present invention, which mainly solves the problems of low switch judgment precision and long time delay in traditional switch process. The method includes the following implementing steps: 1) adopting an R value, obtained by weighting and compounding the RSSI and LQI, as a system preset parameter; 2) utilizing the R value for subnet selection, especially when a pre-addition fails, a pre-adding flow is restored rapidly, so that scanning time delay and signalling interactive times are reduced; 3) preestimating geographical positions when pre-switching, and determining a subnet covering the next moment position of a mobile user, so that times of scanning subnets and switch time delay are reduced; and 4) utilizing a progressive judgment rule so as to avoid error switch and ping-pong effect to a great extent. With the method, network capability is effectively balanced, and network life is prolonged. The method is suitable for the sensor network field which has high requirements on switch performance and is sensitive to switch time delay.