The Key Technology Research In Intelligent Monitoring Based On Airborne Video Wireless Sensor Network

With the continuous development and innovation of human society, requirements of people for danger early warning and real-time monitoring after danger happened are more and more urgent. The background environment in real application of warning and monitoring is relatively complex, especially in mountains, forests and urban full of high buildings. AVWSN(Airborne Video Wireless Sensor Network) was increasingly wide used in danger warning for sensitive military targets, fire rescue of high buildings and other special applications. AVWSN which based on Airborne Wireless Sensor Networks is a new intelligent sensor network. The nodes in this network have independent mobility and visual perception. This paper focused on these two points, achieved intelligent monitoring for special area by guiding nodes independent mobile correctly and delivering video information timely and accuratelyFollowing works have been done in this paper:1) An improved Three-dimensional Space Self-deployment Algorithm Based on Virtual Force Compensation. The targets in wireless sensor network of three-dimensional space were complex and diverse which would lead to appear the “deployment hole”,make it is difficult to achieve uniform deployment. To solve this problem this paper achieves a three-dimensional space self-deployment based on virtual force compensation.First to establish nodes model and coverage targets model. Second, the traditional virtual force algorithm was extended from two-dimensional space to three-dimensional space.The concept of virtual force compensation for coverage target was proposed so that nodes in the network could cover the target uniformly based on the characteristics of target.Finally, the simulation experiments showed that this algorithm has greatly improved two important indicators: coverage and uniformity.2) A Three-dimensional Space Target-area Coverage Algorithm Based on Virtual center of Circle. First to introduce the existing sector node models and analyzed the relative merits of these models. Then a sector node model based on virtual center of circle was improved. This model could transform target area coverage problem for sector nodes into relatively mature problem for circular nodes. Proposed a two-dimensional plane and three-dimensional space target area coverage algorithm. Finally, coverage results were showed by simulation by experiments.3) Improvements to Video Transmission for AVWSN. To solve the problem of longtime delay and frames missing, achieved a real-time video transmission method based on intra-frame compression. This method compressed those video image data before sent them. Then, aimed at the problem that the video was not clear enough, this paper elaborates an adaptive real-time video transmission method based on Bayesian classifier.Bayesian theory gave us the adaptive threshold through calculating. Compression process adjusted the compression quality factor timely based on network’s real-time bandwidth in this method. Finally, verified this optimized method by simulation experiments.At last, achieved the process of self-deployment, regional coverage and video optimization transmission for AVWSN using these three algorithms combined a four-rotor aircraft.