Hyperbolic Localization Algorithm in Mixed LOS- NLOS Environments

A residual hypothesis test algorithm (RHTA) for hyperbolic localization in mixed LOS-NLOS environments is proposed in this paper. The residual, referred to as the difference between the initial and the improved position estimate presented by CHAN's algorithm as a well-known estimator for hyperbolic location, is selected as an object of hypothesis test to distinguish line-of sight base stations (LOS-BS) from non-line-of-sight base stations (NLOS-BS) without any prior information about NLOS measurements. Then, localization can proceed with only the LOS-BS. The Monte-Carlo experimental results show that RHTA can greatly mitigate the positioning error caused by NLOS, and the root mean square errors (RMSE) of RHTA follows the Cramer-Rao Lower Bound (CRLB) at low noise level.