Browsing by Subject "Range estimation"

Now showing 1 - 4 of 4

Open Access
Enhancements to threshold based range estimation for ultra-wideband systems
(IEEE, 2014-09) Soğancı, Hamza; Gezici, Sinan; Güldoğan, M. B.
Ultra-wideband (UWB) signals have very high time resolution, which makes them a very good candidate for range estimation based wireless positioning. Although the accuracy is the major concern for range estimation, it is also important to have low-complexity algorithms that can be employed in real time. In this study, two low-complexity range estimation algorithms are proposed for UWB signals, which achieve improved performance compared to the state-of-the-art low-complexity ranging algorithms. The proposed algorithms are inspired from two well-known algorithms; 'serial backward search' (SBS) and 'jump back and search forward' (JBSF). Performances of the proposed algorithms are compared with those of the SBS and JBSF algorithms based on real measurements. In addition, theoretical bounds are calculated in order to quantify the statistical performance of the algorithms. © 2014 IEEE.
Open Access
Fundamental limits on RSS based range estimation in visible light positioning systems
(IEEE, 2015-12) Gonendik, E.; Gezici, Sinan
In this study, theoretical limits are obtained for the accuracy of range (distance) estimation in visible light positioning (VLP) systems. In particular, the Ziv-Zakai bound (ZZB) and the weighted Cramer-Rao bound (WCRB) are derived ´ for range estimation based on received signal strength (RSS) measurements. Also, the maximum a posteriori probability (MAP) and the minimum mean-squared error (MMSE) estimators are obtained for RSS based range estimation, and compared against the theoretical limits.
Open Access
A new method for range estimation using simple infrared sensors
(IEEE, 2005-08) Yüzbaşıoǧlu, Çağrı; Barshan, Billur
We describe a new method for position estimation of planar surfaces using simple, low-cost infrared (IR) sensors. The intensity data acquired with IR sensors depends highly on the surface properties and the configuration of the sensors with respect to the surface. Therefore, in many related studies, either the properties of the surface are determined first or certain assumptions about the surface are made to estimate the distance and the orientation of the surface relative to the sensors. We propose a novel method for position estimation of surfaces with IR sensors without the need to determine the surface properties first. The method is considered to be independent of the type of surface encountered since it is based on searching the position of the maximum value of the intensity data rather than using absolute intensity values. The method is verified experimentally with planar surfaces of different surface properties. An intelligent feature of our system is that its operating range is made adaptive based on the maximum intensity of the detected signal. The absolute mean range error for the method resulting in the lowest errors is 0.15 cm over the range from 10 to 50 cm. The cases where the azimuth and elevation angles are nonzero are considered as well. The results obtained demonstrate that IR sensors can be used for localization to an unexpectedly high accuracy without prior knowledge of the surface characteristics. © 2005 IEEE.
Open Access
Range estimation using simple infrared sensors without prior knowledge of surface parameters
(IEEE, 2004) Yüzbaşıoğlu, Çağrı; Barshan, Billur
This paper describes a new method for range estimation using low-cost infrared sensors. The intensity data obtained with infrared sensors depends highly on the surface properties and the configuration of the sensors and the surface. Therefore, in many of the related studies, either the properties of the surface are determined first or certain assumptions about the surface are made in order to calculate the distance and the orientation of the surface relative to the sensors. In this paper, we propose a novel method for position estimation of surfaces with infrared sensors without the need to determine the surface properties first. The method is verified experimentally with planar surfaces covered with white paper, wooden block, bubbled packing material, white styrofoam, blue and brown cardboard. The overall absolute mean error in the range estimates has been calculated as 0.21 cm in the range from 12.5 to 45 cm. The results obtained demonstrate that infrared sensors can be easily used for localization to an unexpectedly high accuracy without prior knowledge of the surface parameters.