Radio communications using ultra wideband (UWB) frequency have rapidly developed since the beginning of the year 2000. This technique offers advantages that made it attractive to a large number of civilian and military applications. The aim of this work is the study of the geometry features of a UWB antenna and the improvement of the bandwidth by inserting slots. To obtain a very large bandwidt...

Detection characteristics, resolution capability, and target coordinates measurement accuracy of Multisite Radar Systems (MSRSs) consisting of Ultra-Wideband (UWB) radars are analyzed. Two types of UWB radars are considered: using short carrier-free pulses and using pulses with carrier frequencies. Target radial dimensions are assumed to be much greater than range resolution cells of UWB radars...

Ultra-wideband (UWB) communications systems provide extremely high data rates while using low transmit power relative to narrowband systems. Recent research concludes that such systems have characteristics that make them appropriate for highspeed wireless network applications. One of the distinguishing aspects of the UWB signal is an extremely high fractional bandwidth when compared with conven...

For an indoor ultra-wideband (UWB) communication system, the line-of-sight (LOS) between the transmitter and receiver may be frequently blocked by moving people. Blocking of LOS may significantly affect the quality of service of on-going UWB communications. Based on the Angular Power Spectrum Density and the human blocking models, we build a packet-level UWB channel model considering the shadow...

There are currently a large variety of wireless access networks, including the emerging vehicular ad hoc networks (VANETs). A large variety of applications utilizing these networks will demand features such as realtime, high-availability, and even instantaneous highbandwidth in some cases. Therefore, it is imperative for network service providers to make the best possible use of the combined re...

In order to estimate performance of Ultra-wideband (UWB) systems and their coexistence with licensed radio services, a characterization of the power spectrum density is required, in particular the influence of the pulse shape used and the pulse repetition rate. In this paper, an improved and faster periodogram algorithm is applied to UWB signals, in order to make use of the special characterist...

The focusing resolution is very important performance for ultra wideband (UWB) imaging system. In this paper, the accuracy of focusing resolution with time-reversal (TR) electromagnetic (EM) pulse propagation is analyzed. The TR EM pulse propagation is done via the numerical simulation of finite difference time domain (FDTD) method. The modulated Gaussian pulse is used as the UWB EM pulse. The ...

Manuscript Received 23-October-2012 and revised 16-Janaury-2013 ISSN: 2322-4088 Accepted on daymonth-year Abstract— In this paper, Ultra-wideband (UWB) multiple access relay channel with correlated noises at the relay and receiver is investigated. We obtain outer and inner bounds for the IEEE 802.15.3a UWB multiple access relay channel, and also, a diversity gain bound. Finally, we evaluate som...

We present experimental demonstrations of in-building impulse radio (IR) ultra-wideband (UWB) link consisting of 100 m multi mode fiber (MMF) and 4 m wireless transmission at a record 4 Gbps, and a record 8 m wireless transmission at 2.5 Gbps. A directly modulated vertical cavity surface emitting laser (VCSEL) was used for the generation of the optical signal. 8 m at 2.5 Gbps corresponds to a b...

---------------------------------------------------------------------------------------------------------------------------------------------Abstract: -In this paper, a compact ultra wideband (UWB) bandpass filter (BPF) with a passband covering 4.73 GHz to 10.43GHz with a bandwidth of 5.7 GHz and a fractional bandwidth of 75.2% is proposed. The filter has three transmission poles in the passban...