Three Dimentional Localization and Locking Toolkits (3DLoc) consists of two main components: a pair of specialized antennas which detect the azimuth and elevation angles of the target device, respectively, and an antenna rotor which rotates the antenna.
Our rotation plan is a two-step process:
- First, we place the azimuth antenna at elevation 0° and rotate it continuously around 360° azimuth surface to determine the azimuth angle of the target device. The elevation antenna is then rotated to this azimuth angle.
- Next, we rotate the elevation antenna continuously to cover the elevation surface and determine the elevation angle of the mobile. The elevation antenna is then rotated to this elevation angle and it should point to the target mobile. Therefore, a rotation time of around 60 seconds for the azimuth and elevation rotations, leading to a total positioning time of around two minutes.
The two specialized antennas feature distinct characteristics: the azimuth antenna has a wide vertical beam width, while the elevation antenna has a narrow one. For the azimuth antenna, the wide elevation beam width is desired so that the azimuth antenna can cover almost the entire elevation surface from 0° to 180° at which the target device may be located. The narrow azimuth beam width is desired so that the azimuth angle of the target device can be determined with smaller error.
For the elevation antenna, we select one with narrow beam width in both azimuth and elevation surfaces. The azimuth beam width can be narrow because the azimuth angle of the target device is already determined by the azimuth antenna in the first step. The narrow elevation beam width is desired so that the elevation angle of the target device can be determined with smaller error.
- Jizhi Wang, Yinjie Chen, Xinwen Fu, Jie Wang, W. Yu and N. Zhang, 3DLoc: Three Dimensional Wireless Localization Toolkit, In Proceedings of the 30th IEEE International Conference on Distributed Computing Systems (ICDCS), 2010, Accept ratio 14.4%.