A Statistical Modelling Versus Geometrical Location Determination Approach for Static Positioning in Indoor Environment (original) (raw)
Many client based positioning systems using received signal strength (RSS) of WLAN (Wireless Local Area Network) are present in the state-of-art. Unfortunately, location precision is limited in most of the cases. Researchers have proposed to integrate different systems to enhance accuracy and coverage which brings a necessity to have a trade off solution over power consumption, computation time and location precision because of constraints at the receiver end. In this paper, statistical modelling versus geometrical ...
Sign up to get access to over 50M papers
Sign up for access to the world's latest research
Related papers
A novel positioning system for static location estimation employing WLAN in indoor environment
2004 IEEE 15th International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE Cat. No.04TH8754)
This paper describes a Positioning algorithm that uses the signal strength, received by a Wireless Local Area Network, to determine users position. The system improves positioning accuracy by mitigating the multi-path and noise, through an empirical analysis of environment and a pre-post curser mitigator. Results, in terms of relative error, are presented for indoor environment.
The work presented here compares the performance of indoor positioning systems suitable for low power wireless sensor networks. Map matching, approximate positioning (weighted centroid) and exact positioning algorithms (least squares) were tested and compared in a small predefined indoor environment. We found that, for our test scenario, weighted centroid algorithms provided the best results. Least squares proved to be completely unreliable when using distances obtained by a propagation model. Major improvements in the positioning error were found when body influence was removed from the test scenario.
Comparison of Performance Evaluation of Several WLAN Positioning Systems
In this paper we evaluate the performance of several indoor positioning systems published in the literature in real and complex scenarios. We include in the comparison the evaluation of our new system for which we study the accuracy and precision in three different scenarios. The impact of AP configuration on our system is also analyzed. Since most of the existing performance evaluations do not consider the environment size and the AP interference, here we use the method of comparison proposed in paper (1) which is more realistic and flexible. The comparative results demonstrate that our system achieves accuracy that is similar to the best existing one.
Int'l J. of Communications, Network and System Sciences, 2009
This paper proposes efficient techniques that allow the deploying of high precision location applications for indoor scenarios over Wireless Local Area Networks (WLAN). Firstly, we compare the use of radio frequency (RF) power levels and relative time delays based on ray-tracing as detection methods to estimate the localization of a set of mobile station using the fingerprint technique. Detection method play an important role in applications of high frequencies techniques for locations systems based on current and emerging standards such as Wi-Fi (802.11x) and Wi-Max (802.16x). The localization algorithm computes the Euclidean distance between the samples of signals received from each unknown position and each fingerprint stored in the database or radio-map obtained using the FASPRI simulation tool. Experimental results show that more precision can be obtained in the localization process by means of relative delay instead of RF power detection method. Secondly, the Euclidean distance has been compared with others similarity distance measures. Finally, an interpolation algorithm between the fingerprinting weighing based on the distances has been implemented in order to eliminate those fingerprints that do not contribute to the improvement in the accuracy. These techniques allow obtaining more precision in the localization of indoor mobile devices over WLAN networks.
Sensors, 2021
Indoor positioning has become a very promising research topic due to the growing demand for accurate node location information for indoor environments. Nonetheless, current positioning algorithms typically present the issue of inaccurate positioning due to communication noise and interferences. In addition, most of the indoor positioning techniques require additional hardware equipment and complex algorithms to achieve high positioning accuracy. This leads to higher energy consumption and communication cost. Therefore, this paper proposes an enhanced indoor positioning technique based on a novel received signal strength indication (RSSI) distance prediction and correction model to improve the positioning accuracy of target nodes in indoor environments, with contributions including a new distance correction formula based on RSSI log-distance model, a correction factor (Beta) with a correction exponent (Sigma) for each distance between unknown node and beacon (anchor nodes) which are ...
Novel Received Signal Strength-Based Indoor Location System: Development and Testing
EURASIP Journal on Wireless Communications and Networking, 2010
A received signal strength-(RSS-)-based indoor location method (ILS) for person/assets location in indoor scenarios is presented in this paper. Theoretical bases of the method are the integral equations relating the electromagnetic (EM) fields with their sources, establishing a cost function relating the measured field at the receivers and the unknown position of the transmitter. The aim is to improve the EM characterization of the scenario yielding in a more accurate indoor location method. Regarding network infrastructure implementation, a set of receivers are deployed through the coverage area, measuring the RSS value from a transmitter node which is attached to the asset to be located. The location method is evaluated in several indoor scenarios using portable measurement equipment. The next step has been the network hardware implementation using a wireless sensor network: for this purpose, ZigBee nodes have been selected. Finally, RSS measurements variability due to multipath effects and nonline-ofsight between transmitter and receiver nodes is mitigated using calibration and a correction based on the difference between the free space field decay law and the measured RSS.
Robust indoor positioning provided by real-time RSSI values in unmodified WLAN networks
2009
The positioning methods based on received signal strength (RSS) measurements, link the RSS values to the position of the mobile station (MS) to be located. Their accuracy depends on the suitability of the propagation models used for the actual propagation conditions. In indoor wireless networks, these propagation conditions are very difficult to predict due to the unwieldy and dynamic nature of the RSS. In this paper, we present a novel method which dynamically estimates the propagation models that best fit the propagation environments, by using only RSS measurements obtained in real time. This method is based on maximizing compatibility of the MS to access points (AP) distance estimates. Once the propagation models are estimated in real time, it is possible to accurately determine the distance between the MS and each AP. By means of these distance estimates, the location of the MS can be obtained by trilateration. The method proposed coupled with simulations and measurements in a real indoor environment, demonstrates its feasibility and suitability, since it outperforms conventional RSS-based indoor location methods without using any radio map information nor a calibration stage.
A NOVEL MODEL-BASED INDOOR POSITIONING USING SIGNAL STRENGTH
A simple technique to estimate the position of a mobile node inside a building is based on the Received Signal Strength (RSS). In a previous publication, we investigated the feasibility of using circular array antennas and beamforming in order to enable an access point to estimate the position of a mobile inside a building. The approach utilized the two dimensional information (i.e. RSS for various azimuth directions) that is captured in a priori measured radio map. Generating these radio maps is not only extremely laborintensive and time consuming but also sensitive to changes in the environment and possible source of interference. It would be interesting to find out if a deterministic propagation model such as ray tracing can be used to construct a radio map that effectively replaces the off-line manual measurements. In this paper, we investigate this issue and provide a novel positioning methodology that exhibits acceptable performance without the need for extensive set of measurements in the off-line mode. The performance for various parameters and building model accuracy will be presented and discussed.
Loading Preview
Sorry, preview is currently unavailable. You can download the paper by clicking the button above.