Kang SeYoung, Kim TaeHyun, Chung WonZoo
Division of Computer and Communications Engineering, Korea University, Seoul 02841, Korea.
Agency for Defense Development, Daejeon 34186, Korea.
Sensors (Basel). 2020 Nov 18;20(22):6582. doi: 10.3390/s20226582.
We present a novel hybrid localization algorithm for wireless sensor networks in the absence of knowledge regarding the transmit power and path-loss exponent. Transmit power and the path-loss exponent are critical parameters for target localization algorithms in wireless sensor networks, which help extract target position information from the received signal strength. In the absence of information on transmit power and path-loss exponent, it is critical to estimate them for reliable deployment of conventional target localization algorithms. In this paper, we propose a simultaneous estimation of transmit power and path-loss exponent based on Kalman filter. The unknown transmit power and path-loss exponent are estimated using a Kalman filter with the tentatively estimated target position based solely on angle information. Subsequently, the target position is refined using a hybrid method incorporating received signal strength measurements based on the estimated transmit power and path-loss exponent. Our proposed algorithm accurately estimates transmit power and path-loss exponent and yields almost the same target position accuracy as the simulation results confirm, as the hybrid target localization algorithms with known transmit power and path-loss exponent. Simulation results confirm the proposed algorithm achieves 99.7% accuracy of the target localization performance with known transmit power and path-loss exponent, even in the presence of severe received signal strength measurement noise.
我们提出了一种新颖的混合定位算法，用于在未知发射功率和路径损耗指数的情况下的无线传感器网络。发射功率和路径损耗指数是无线传感器网络中目标定位算法的关键参数，它们有助于从接收信号强度中提取目标位置信息。在缺乏发射功率和路径损耗指数信息的情况下，为了可靠地部署传统目标定位算法，对它们进行估计至关重要。在本文中，我们提出了一种基于卡尔曼滤波器的发射功率和路径损耗指数同时估计方法。使用卡尔曼滤波器，仅基于角度信息初步估计目标位置，进而估计未知的发射功率和路径损耗指数。随后，基于估计的发射功率和路径损耗指数，使用结合接收信号强度测量的混合方法对目标位置进行优化。我们提出的算法能够准确估计发射功率和路径损耗指数，并且正如仿真结果所证实的那样，与具有已知发射功率和路径损耗指数的混合目标定位算法相比，能够产生几乎相同的目标定位精度。仿真结果证实，即使在存在严重的接收信号强度测量噪声的情况下，所提出的算法在已知发射功率和路径损耗指数时，目标定位性能的准确率也能达到99.7%。
