Research On Data Aggregation Technology In6LoWPAN Networks

Implemented by6LoWPAN technology,6LoWPAN is essentially specialWireless Sensor Networks (WSNs) which densely deploys a large number of nodes,collects data cooperatively.6LoWPAN nodes collect a large amount of highlyredundant data. Data aggregation technology is a significant method to reduce theamount and redundancy of transmission data. Based on the characteristics of6LoWPAN, the research on designing efficient data aggregation method to reducethe amount and redundancy of transmission data will directly affects whether6LoWPAN can be widely used. Therefore, data aggregation technology of6LoWPAN is the focus of this paper.Firstly, the existing data aggregation algorithms based on compressed sensingare detailedly analyzed and compared. According to the characteristics of6LoWPAN,this paper proposes a data aggregation algorithm based on compressed sensing,which firstly introduces the data compression method of compressed sensing into6LoWPAN. The algorithm is divided into two phases. In the network initializationphase, network topology which can effectively apply compressed sensing isgenerated in the region of interest. It improves load balancing problem of networknodes. In the data acquisition phase within the region of interest, nodes drop packetsselectively according to the spatial correlation of data to reduce data redundancy.And then it dynamically updates the spanning tree through father node selectionalgorithm of compressed sensing, which improves traditional data aggregationmethods of compressed sensing and makes a higher rate of data aggregation innetwork. Simulation results show that the algorithm can effectively improve the dataacquisition efficiency of compressed sensing, reduce energy consumption of nodesand extend the network life cycle.Secondly, because of the limited bandwidth of6LoWPAN channel, thetransmission of large amounts of data will cause the problem of increasing collisionsand delay along with the increase of network load. According to the problem,through the analysis of6LoWPAN protocol stack structure, this paper designs andrealizes the6LoWPAN protocol stack based on data aggregation. In the adaptationlayer, the data aggregation function is realized and then a dynamic data aggregationalgorithm based on aggregation conditions is proposed. The algorithm defines data aggregation elements and simplifies the process of data aggregation operation.During the data aggregation process, the algorithm estimates the real-time degreeaccording to aggregation conditions in the aggregation polices. In addition, thechained mode of hash table storage structure is applied to store data that need to beaggregated. The algorithm dynamically sets the degree of the aggregation based onload of network to reduce the collisions in network. Simulation results show that thealgorithm is capable of meeting data real-time requirement, effectively reducing theamount of transmission data, increasing the utilization ratio of radio channel andreducing nodes energy consumption.