Research On Optimization Algorithms For Hole-bypassing Route In Wireless Multimedia Sensor Networks

With the development of the technologies in embedded system, communication, sensor, and coding, wireless multimedia sensor networks (WMSNs) have made great progress. Because they can be widely used in biomedical surveillance, target tracking control, and military fields, so they have high research value.Because of large volume of data and node power constraint in WMSNs, energy consumption becomes one of the issues that constraint the development of WMSNs. It is an effective way to save energy that shorter paths are used to transmit data. In realistic applications, because of topography, such as Lakes, marshes, etc., energy depletion and overload and other reasons, holes are unavoidable. Because of the existence of holes, the routing algorithms in WSNs must have the ability of hole-bypassing.The routing algorithms based on position information can avoid flooding exploring packets blindly, and it can also find and maintain effective routes, so the routing algorithms based on position information are a kind of realistic routing algorithms in WMSNs.Most of the existing the routing algorithms based on position information are greedy and distributed. Because the information each node uses when choosing a route is not the overall information but the local information, so the route they get is much longer than the ideal one (the shortest path). Motivated by this we provide an algorithm that can optimize the routes generated by the routing algorithms based on position information.In this paper, the existing routing algorithms is studied, and two routing optimization algorithms are provided one is a Heuristic Optimization algorithm for Geographic Greedy Hole-Bypassing routing algorithms based on crItical nodes (HOGGHI) and the other is a Heuristic Optimization algorithm for Geographic Greedy Hole-Bypassing routing algorithms based on crEst nodes (HOGGHE). HOGGHI is based on critical nodes, and HOGGHE is based crest nodes. The first step of the two algorithms is to explore the existing route, and find all the critical nodes (or crest nodes), and then optimize the route according to the information they get.Through optimizing the routes by passing holes, the routes are made shorter, which lead to less energy consumption and prolonged life of the network. Meanwhile, the overhead of the two algorithms is little, and besides the information needed by the original routing algorithms, only information about critical nodes array is needed by HOGGHI, and crest nodes array is needed by HOGGHE...