This paper presents the results from an ultra wideband (UWB) indoor measurement campaign and describes a 3D beam trace pyramidal method that allows one to characterize the channel over a bandwidth of 850 MHz. The UWB channel characteristics are assessed in terms of mean delay, delay spread and coherence bandwidth.

Due to the low complexity and cost characteristics of ultra-wideband (UWB) systems, a weighted acquisition algorithm based on energy detection is proposed in this paper. This method is divided into two steps to acquire the direct path (DP) component. Firstly, weighted energy detection is applied to determine which energy block the DP lies in by generalized likelihood ratio test (GLRT). A sub-op...

iii Sammanfattning v Preface vii Contributions ix Abbreviations xi Acknowledgments xiii

This is a discussion document for the IEEE document of the IEEE 802.15.4a channel modeling subgroup. It gives the current status of the generic channel model for UWB that has been discussed. Feedback from all participants is requested.

Ultra Wide Band (UWB) wireless communications offers a radically different approach to wireless communication compared to conventional narrow band systems. Global interest in the technology is huge. This paper reports on the state of the art of UWB wireless technology and highlights key application areas, technological challenges, higher layer protocol issues, spectrum operating zones and futur...

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A dislocation bow-out model has been developed to explain the strength of ultra-fine grained (UFG) materials with grain size roughly between 20 nm to 500 nm. In the model, perfect dislocations are assumed to be nucleated at grain-boundary sources and bow out between two pinning points on a boundary. Yielding is considered to occur when a dislocation takes a semi-circular shape under applied str...

Radio communications via channels already occupied by traditional telecommunication systems can be achieved by using ultrawideband (UWB) radio where extremely wideband wavelets are used in order to reduce the power spectral density (psd) of transmitted signal. Since the recovery of these UWB carriers is not feasible, noncoherent demodulation techniques have to be used. The letter evaluates and ...

UWB (Ultra Wide-Band) pulse radar is promising for surveillance systems because it has an outstanding high range-resolution. To realize an accurate UWB radar imaging system, we propose a new approach that employs multipath echoes from a target in an indoor environment. Using multipath echoes, the proposed system can accurately estimate images, even for targets in a shadow region where the targe...