Pseudorange error analysis for precise indoor positioning system

Abstract

There is a currently developed system of a transmitter indoor localization intended for fire fighters or members of rescue corps. In this system the transmitter of an ultra-wideband orthogonal frequency-division multiplexing signal position is determined by the time difference of arrival method. The position measurement accuracy highly depends on the directpath signal time of arrival estimation accuracy which is degraded by severe multipath in complicated environments such as buildings. The aim of this article is to assess errors in the direct-path signal time of arrival determination caused by multipath signal propagation and noise. Two methods of the direct-path signal time of arrival estimation are compared here: the cross correlation method and the spectral estimation method.

Design and Experiment of Assistive Mechanism for Adjustment of Transrectal Ultrasound Probe

“…Most random errors follow a normal distribution. To reflect the spatial relationship of random stochastic processes in different spatial locations, the value of the random error parameters ranged from -1 to 1 [ 27 , 28 ]. The x and y direction and the x and z directions of the azimuth and pitching angles were used as the positioning quality indicators as two sets of 2D random variables.…”