Location-based Mechanism for Positioning of a Mobile Relay

Abstract

Leveraging a relay for communication is a promising approach for improving throughput, coverage, and energy e ciency in wireless networks. If the destination device is nomadic, transmi ing through a relay that is always at the same location is usually suboptimal in terms of maximizing the bene ts of relaying. A mobile relay that is capable of positioning itself at di erent locations opens the possibility for dynamic optimization of the path quality between the source and the nomadic destination. How to optimally position the mobile relay in order to maximize the path quality, however, remains a challenging task. Under the assumption that the physical location information of the devices are either known or can be estimated, we propose a mechanism for positioning of the mobile relay with the aim of maximizing the Signal-to-Noise Ratio (SNR) between the source and the destination. e proposed mechanism takes into account the practically unavoidable inaccuracies of estimated locations, as well as the propagation characteristics of the served environment. Using WiFi as an example technology, we experimentally evaluate the proposed mechanism in a complex indoor environment with the support of a speci cally designed testbed infrastructure. For relatively small localization errors, our results show less than 4 dB average di erence between the measured SNR at optimal locations of the mobile relay vs. the SNR at locations yielded by our positioning mechanism. Our results also illustrate how the quality of the paths created by the proposed positioning mechanism degrades in the face of increasing localization errors.

Regression-Based Estimation of Individual Errors in Fingerprinting Localization

“…erroneous) location information for improving the performance of wireless networks. By showing that the overestimation of expected localization errors substantially degrades the performance of the proposed mechanisms, [14] and [15] also motivate the need for an accurate estimation of the localization error for each location estimate. Finally, [16] motivates the need for estimating the accuracy of provisioning of location information without knowing upfront the location estimate.…”

“…Some examples also exist in the domain of context-aware communication. Nielsen et al [13] and Lemic et al [14] present location-based mechanisms for selection and positioning of (mobile) relays in wireless networks, respectively. In their operations, both mechanisms utilize the expected localization errors together with the location information of the devices participating in communication.…”