Rigid Body Localization Based on Conformal Sensor Array in Non-Line-of-Sight Environment

In the wireless sensor network (WSN) based rigid body target localization systems, the error caused by the non-line-of-sight (NLoS) transmission of wireless signal can seriously deteriorate the localization accuracy. To improve the estimation performance of rigid body posture, including the parameters of the position and the direction, a rigid body localization (RBL) technology is proposed based on the semi-definite programming (SDP) with NLoS error elimination. By taking the unknown NLoS errors as the balancing parameters in the received signal strength (RSS) model, the results of the maximum likelihood estimation (MLE) is obtained according to a nonlinear least squares (NLS) problem, which is solved by using the semi-definite relaxation (SDR) method. The obtained balancing parameters are then re-substituted into the model to refine the parameters in the semi-definite programming problem to mitigate the effect of the NLoS error on the localization performance. Finally, the singular value decomposition (SVD) is used to solve the parameters of rigid body posture. The effectiveness of the algorithm is verified by computer simulation.