The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The rapid development of intelligent terminals and mobile Internet industry has brought many challenges and opportunities to the mobile network. Mobile Network Open Services can provide users and developers with the open resources consisted of network infrastructure, network data and diversified services, so as to build an open, flexible, collaborative Internet ecosystem. The ability to open the mobile...
In this paper a simple algorithm for the estimation of the Direct Path (DP) Time of Arrival (TOA) in an OFDM-based telecommunications system is proposed. It is shown that, under certain conditions, it is possible to infer the TOA of the direct path by estimating the phase slope across the subcarriers. The proposed algorithm exploits the intrinsic properties of a multi-carrier OFDM system to perform...
Intelligent Transportation System (ITS) applications for integral and cooperative vehicle safety as well as some Advanced Driver Assistance Systems (ADASs) benefit from highly accurate positioning. Shared position data between dynamic traffic objects via Inter-Vehicle Communication (IVC) are the backbone for deriving vehicle trajectories. These can be used for assessing a situation's criticality in...
Tropospheric signal delay can introduce a considerable error in satellite positioning if it is not properly modeled. In this work, the spatial and temporal variations of the zenith tropospheric delay (ZTD) over low latitude and complex topography of Ethiopia and Eritrea from the Greater Horn of Africa (GHA) region, are analyzed using ECMWF (European Center for Medium-Range Weather Forecast) pressure-level...
Localization in urban areas with no direct line-of-sight between the target and anchor nodes turns out to be challenging for many well-known localization methods. In combination with multipath propagation of employed radio waves, the performance of the location estimates can be heavily deteriorated. In this paper we introduce a multilateration method that is able to cope with such conditions. Employing...
The satellite navigation is supposed to be used in applications that need coordinates generally. However we can meet a plenty of satellite signal reception problems in a real environment, often called as difficult conditions. The difficult conditions hinder reliable positioning with required accuracy, often in applications that are important for saving or securing the safety of human lives (work of...
An impulse radio (IR) 60 GHz positioning system is proposed to provide accurate positioning. Two typical IR signals for positioning systems, namely polarity codes and pulse position modulation (PPM), are considered. The ranging and positioning accuracy and reliable distance in residential environments are investigated. Both line-of-sight (LOS) and non-line-of-sight (NLOS) channels are examined. Simulation...
High resolution radio based positioning and tracking is a key enabler for new or improved cellular services. In this work, we are aiming to track user movements with accuracy down to centimeters using standard cellular bandwidths of 20–40 MHz. The goal is achieved by using phase information from the multi-path components (MPCs) of the radio channels. First, an extended Kalman filter (EKF) is used...
A new wireless tag design for a precise ranging system is presented. The proposed approach, based on a SAW delay line, is optimized for very low-power operation and low-cost manufacturing without compromising the measurement accuracy. Furthermore, the tag architecture allows the simultaneous use of the 2.4 GHz and the 5.8 GHz ISM bands, which may be used to improve the measurement resolution and accuracy...
In many medical applications, it is necessary to precisely control a robot to achieve exact positioning. In such cases, some components of robot which had been considered rigid should be modeled with visco-elastic elements to present more exact model of robot, and hence controllers designed under the assumption of rigidity may not accurately control them, especially when time-delay and disturbances...
In recent years wireless local area networks constantly grew in popularity, mainly due to widely deployed IEEE 802.11 standards family. The number of applications that might benefit from those standards increases constantly. We witness this "all wireless" trend, where wireless connectivity is not just about Internet access any more. Numerous WLAN applications have emerged mobile VoIP telephony,...
Considering eye-in-hand visual servoing, a new vision open-loop system scheme is proposed, this method evades the hardness of constructing image Jacobian, and needn't update or invert Jacobian at all time, the delay produced by low sampling rates and burden of computing is weakened, system performance is very improved. In order to verify the scheme, simulation of a 2 DOF manipulator eye-in-hand visual...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.