Simulation on Query System of Sensor Networks Based on Hybrid Index Structure
Nan Guo-fang · Jisuanji fangzhen · 2011
Querying sensed data of k nearest neighbors to a fix node q in the field is of great importance for time-spatial query problem in wireless sensor database system.Integrating two types of query frameworks based on index structure or non-index structure,a novel nearest neighbors query model and the corresponding query algorithm based on the hybrid index structure was proposed.The key step of the hybrid index structure was that the query package was transferred to the given point q using the greedy geographic routing algorithm which was not based on the index structure.After receiving the query package,the point q estimated the search region based on the number k.Finally,the interesting data within the search region was retrieved using the improved index structure method.Meanwhile,a heuristic nearest neighbors query algorithm for dynamic topology structure in mobile wireless sensor network applications was proposed.The proposed algorithm was simulated through lots of experiments.Simulation results show that hybrid index structure combines the advantage of index structure and non-index structure,achieving the purpose of low energy system consumption and high quality of service.