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We present experimental evaluations of human-induced perturbations on received-signal-strength-(RSS-) based ranging measurements for cooperative mobile positioning. To the best of our knowledge, this work is the first attempt to gain insight and understand the impact of both body loss and hand grip on the RSS for enhancing proximity measurements among neighbouring devices in cooperative scenarios. Our main contribution is represented by experimental investigations. Analysis of the errors introduced in the distance estimation using path-loss-based methods has been carried out. Moreover, the exploitation of human-induced perturbations for enhancing the final positioning accuracy through cooperative schemes has been assessed. It has been proved that the effect of cooperation is very limited if human factors are not taken into account when performing experimental activities.

In this paper we present experimental evaluations of cooperative ranging-based approaches in mobile positioning. Our main contribution is represented by experimental investigations of the errors introduced by the hand-grip effect on cooperative schemes among peer devices, demonstrating that by knowing in real-time the particular orientation of the MS in a controlled experimental environment, it is possible to mitigate and filter out the effect of the hand-grip on RSS measurements and consequently to maintain the beneficial effect of the cooperation in the final position estimation.

In this paper we present experimental evaluations of cooperative ranging-based approaches in mobile positioning. Our main contribution is represented by experimental investigations, analysis of the errors introduced in the distance estimation and exploitation of the knowledge of environmental perturbations with a NLLS algorithm, highlighting the limits of such cooperative schemes, proving that the effect of cooperation might be very limited in real-life scenarios.

This paper deals with the propagation channel challenges affecting indoor positioning. Several methods are reviewed and experimental results are provided, showing that the pathloss method is preferable with respect to fingerprinting because of its intrinsic complexity and uncertain effective reliability under real-world conditions. Moreover the influence of the user and the heterogeneity of the devices pose a high challenge on the positioning accuracy.

In this paper we present the effect of the hand-grip and the presence of the human body on received signal strength measurements when performing positioning of mass market devices in indoor environments. We demonstrate that the mitigation of both human body and hand-grip influence can enhance the positioning accuracy and that the human factor cannot be neglected in experimental activities with real mobile devices.

In this paper we propose a Collaborative Mapping (CM) method based on the exploitation of the WLAN Received Signal Strength (RSS) measured from short-range ad-hoc links between neighboring devices. The estimated spatial proximity allows on-the-fly calibrations of heterogeneous clients for Location Fingerprinting (LF) applications. This method can avoid long time-consuming and battery-draining calibrations when implementing Fingerprinting Location applications running on heterogeneous mass market devices.

In this paper, we propose a solution for avoiding extensive time consuming path loss calibrations when performing RSS-to-distance conversions for indoor mobile positioning with heterogeneous mobiles. By exploiting RSS measurements and ad-hoc link communications we prove the concept of cooperative calibration and demonstrate it in a WLAN 802.11 network. Moreover the results obtained in the cooperative calibration phase will be applied to the cooperative mobile positioning algorithm developed in previous works.

In this paper, we exploit the concept of cooperative localization by utilizing the additional information obtained from short-range links to enhance the location estimation accuracy in forthcoming cellular systems. Simulations for a hybrid WiMAX/Wi-Fi system are carried out considering an outdoor environment, where time difference of arrival (TDOA) and received signal strength (RSS) measurements are combined thanks to advanced data fusion techniques. Results show that the proposed system allows to meet the federal Communications Commission (FCC) requirements and overcome the ever changing channel conditions.