Cooperative diversity has emerged as a major technique of providing gains from spatial diversity to devices/terminals. While ultra-wideband (UWB) offers high information rates for wireless communication and sensor networks, the EIRP limits on UWB devices severely affects its coverage radius. In this paper, a low complexity cooperative diversity scheme for UWB channel is proposed. The scheme use...

This paper reports an evaluation of UWB radio technology and Time-Reversal (TR) technique in tunnel environments for train-to-wayside communication. UWB technology has the potential to offer simultaneous ground-totrain communication, train location and obstacle detection in front of the trains. Time-Reversal channel pre-filtering facilitates signal detection and helps reduce interference. Thus,...

The technology for through-wall human detection with ultra-wideband (UWB) radar was discussed. Due to the large amount of UWB radar data, compressive sensing theory was introduced and compressed UWB radar data can be collected. The singular value decomposition algorithm was used to acquire the singular values of compressed radar data. The compressed UWB radar data were collected at two statuses...

Ultra-wideband (UWB) bandpass filters play a key role in the development of UWB systems. In this paper, we present a review on their development since the release of UWB band for indoor and hand-held systems by Federal Communications Commission (FCC) in 2002.

Performance evaluation of time-hopping UWB using various modulation techniques has been proposed. Then the performance improvement is analysed based on the BERs of various existing methods. Recently a new method called TH-BPSK UWB system is proposed which provides a better performance than all other existing systems. The literature survey discusses all the existing techniques of UWB communication.

The aim of this document it to present an overview of some recent research activities on ultra–wideband (UWB) channel modeling. Compared to models introduced in DRB1.2, recent research was focused on more sophisticated tools to model UWB channels, like information theoretic arguments. Physical modeling of UWB channels was also investigated. Reference D.xx.xx Issue n.m 4 November 2006 507325 NEW...

-In ultra-wideband (UWB) impulse radio (IR) technology, it is important that the pulse shape be adjusted such that the power spectral characteristics not only satisfy the standard limits, but also be characterized by deep nulls at the locations of existing narrowband primary users. Cognitive Radio Technology (CR) is presented as a viable solution for UWB systems for narrowband interference supp...

Power control is a critical parameter for the design and evaluation of UWB-based WPAN networks due to its distributed control nature and non-fixed topology. The main issues in UWB PC are the channel gain fluctuations induced by indoor channel fluctuation and interference arising from narrowband systems. In this paper we introduce a joint PHY/MAC technique for DS-UWB power control design by expl...

In this paper, the significance of linearity for UWB front-end circuit is discussed. The effects of strong narrow band interferer on UWB signal are investigated. Wideband linearization techniques for UWB LNA are first proposed in this work. A high linearity UWB LNA is designed in TSMC 0.18μ CMOS process The simulation results show that the designed LNA exhibits very high IIP3 (6.9~13.8 dBm) whi...

In this paper, we present an ultra-wideband (UWB) pulse generator based on the step recovery diode. The principle of operation and the architecture of the developed pulse generator are explained. Furthermore, hardware implementation issues and the details on the generated UWB pulse including its peak voltage equal to 8.9 V, its full width at half maximum (fwhm) equal to 240 ps, and frequency sp...