Performance Evaluation of Threshold -Based TOA Estimation Techniques Using IR-UWB Indoor Measurements

International audienceUltra-wide bandwidth (UWB) technology is a viable candidate for enabling accurate localization through time of ar- rival (TOA) based ranging techniques. These ranging techniques exploit the high time resolution of the UWB signals to estimate the TOA of the first signal path. Nevertheless, these techniques are facing the problem of proper multipath mitigation especially in harsh propagation environments in which the first path may not exist or it may not be the strongest. This paper presents a realistic comparison between the ranging performances of four threshold-based TOA estimation techniques using experimental data collected from an IR-UWB indoor propagation measurement campaign performed in an office building

Rate adaptive resource allocation with fairness control for OFDMA networks

The use of opportunistic radio resource allocation techniques in order to efficiently manage the resources generates a low fairness among the users in a cellular system due to uneven Quality of Service (QoS) distribution. Some classic rate adaptive policies tried to tackle this problem for OFDMA systems by proposing solutions to maximize capacity, maximize fairness, or find a static trade-off between these two objectives. This work generalizes these classic policies and propose a dynamic fairness/rate adaptive technique based on dynamic sub-carrier assignment and equal power allocation that considers a new fairness constraint in the optimization problem. By means of extensive system-level simulations, it is demonstrated that the proposed technique is able to provide an instantaneous (short-term) fairness control, which provides to the network operator the flexibility to operate on any desired trade-off point.Peer ReviewedPostprint (published version