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The Authentic 3D Mobility Model Based on Spiral Line for Aerial Backbone Network

For search and rescue (SAR), the dynamic connectivity issue caused by mobility of aerial node will severely influence the actual performance in aerial backbone network (ABN). To capture true aerial mobility feature, some application-oriented aerial mobility model (AMM) has been developed. However, existing 3D AMM cannot satisfy some specific demands for in SAR, especially smooth 3D trajectory and rapid connectivity coverage. In this paper, we propose authentic 3D mobility model based on spiral line (3D SLMM), such as Z-Or-SLMM and Z-Non-SLMM. Firstly, we review the basic concept of 2D SLMM. Then, we develop authentic 3D SLMM based on 2D SLMM. Meanwhile, we validate synthetic trajectory of 3D SLMM through the real traces. In the further, we investigate some mathematical features of 3D SLMM, such as mathematical expression and the distribution of spatial nodes. Finally, we evaluate some key mobility property of 3D SLMM. The result shows that Z-Or-SLMM and Z-Non-SLMM all have specific mathematical expression and uniform distribution of spatial nodes at steady status. Besides, the Z-Or-SLMM and Z-Non-SLMM all possess authentic and smooth 3D trajectory. Specially, the aerial node in Z-Or-SLMM merely takes 1.5 minutes to cover 100% target region of 200m*200m. We believe that the 3D SLMM can be directly deployed in the actual scene, and provide many helpful and credible guidelines in the design and analysis of realistic ABN.