RSSI-and-LQI-based rapid switch method in wireless sensor network

Abstract

The invention discloses a rapid switch method based on received signal strength indicator (RSSI) and link quality indicator (LQI) in a wireless sensor network, mainly solving the problems of low switch judgment precision and long time delay in the traditional switch process. The method is implemented by the following steps: 1) adopting an R value obtained by weighting and compounding the RSSI andLQI as a system preset parameter; 2) utilizing the R value for subnet selection, and reducing interactive times of scanning time delay and signalling by rapidly restoring a pre-adding flow especiallywhen pre-addition fails; 3) predicating geographic positions when in pre-switch, determining a subnet covering the position of a mobile node the next moment, and reducing the scanned subnet amount and switch time delay; and 4) utilizing a progressive judgment rule so as to avoid false switch and ping-pong effect. The method can effectively balance network capability, prolongs network life, and issuitable for the sensor network field which has high requirements on switch performance and is sensitive to switch time delay.

Description

technical field [0001] The present invention relates to the field of short-distance wireless communication, in particular to a mobile user switching scheme in a wireless sensor network clustering model, specifically a fast switching method based on a signal strength indicator RSSI and a link quality indicator LQI in a wireless sensor network. In the application scenarios that need to provide mobile users with high switching performance, low latency and low energy consumption. Background technique [0002] Wireless sensor network is a brand-new information acquisition platform. It has incomparable advantages in information acquisition compared with other networks. It can monitor and collect information of various monitoring objects in the network distribution area in real time to achieve complex targets within a specified range. Detection and tracking can greatly make up for the shortcomings of wireless network information collection. It has the characteristics of rapid deplo...

AI Technical Summary

Problems solved by technology

[0008] Because RSSI is greatly affected by the environment, and sometimes the change of RSSI is not caused by the mobile users being far away from the cluster head node, but also by multiple mobile users competing for channels or signal interference between multiple nodes, so only relying on The scheme where RSSI is used as the reference quantity of the judgment criterion often leads to wrong switching or frequent switching, which not only wastes a lot of network resources, but also increases the packet loss rate and decreases the network throughput. In extreme cases, it may also cause long service time interruption

[0009] 2) When it is determined that switching is required, the mobile user needs to scan all subnets during the scanning phase, obtain the information therein, and decide which subnet to switch to, which will cause a waste of time

However, the reality is that the subnets that mobile users will access only need to be selected from several adjacent subnets. Scanning all subnets will not only waste time, but also cause the longest delay in the scanning phase, which reaches About 90% of the entire switching delay

[0010] 3) If the handover fails due to some reason, the mobile node will directly disconnect and start the whole handover process again, which will not only increase the energy consumption of the network, reduce the life of the network and generate frequent signaling interactions, but also make the provided Service interruptions, especially for businesses with high real-time requirements, can bring intolerable consequences

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