Access point-less wireless location method based on peer-to-peer ranging of impulse radio ultra-wideband

This study describes an efficient wireless location method for access point (AP)-less environments based on peer-to-peer (P2P) ranging of the impulse radio ultra-wideband (IR-UWB). In order to achieve an accurate ranging, which is a basal condition for the accurate wireless location, IEEE 802.15.4a-based IR-UWB is selected as a localisation infrastructure. The IR-UWB can provide the accurate ranging information. However, the coverage of IR-UWB is as short as 30 m owing to the restriction of the power spectral density, that is, 41.3 dBm/MHz. This fact as well as the AP-less environment is the motivation of this study. To extend the coverage of localisation in the AP-less area, an efficient localisation method based on the P2P ranging between IR-UWB tags is presented. In the proposed method, iterative least square (ILS) and direct solution (DS) methods are used together for an estimation algorithm. This study also provides the clues for solving the problems that the ILS and DS methods have. Then the performance of the proposed method is verified by a Monte-Carlo simulation using the analysis tool developed in this work.