An adaptive beamforming method for ultrawide-band (UWB) array in the case of nearfield is proposed based on the radical basis function neural network (RBFNN) in this paper. The desired outputs corresponding with measured inputs for the nearfield impulse source are reflected into a set of training samples. Genetic algorithm and recursive least square algorithm are employed to determine the struc...

This note applies Variable 0 Z technology to the design of an Ultra Wideband (UWB) YagiUda array optimized using Central Force Optimization. Variable 0 Z is a novel and proprietary approach to antenna design and optimization that treats the feed system characteristic impedance, 0 Z , as a design variable instead of a fixed design parameter as is traditionally done. Variable 0 Z is applicable to...

The modified aspects for simulating UWB multipath channels are presented in this paper. Pulse distortion mechanisms based on the geometric optics and the geometric theory of diffraction are specifically generated combing with the spatio-temporal characteristics of multipath clusters based on 3x3 planar array systems. In each particular scenario, model parameters such as angle-of-arrival, angle-...

This paper presents a review of Ultra Wide Band (UWB) communication system and its application for the indoor environment, in general, and in underground mine environment. It shows that, to improve the UWB system performance many researcher proposed the modification in transmitting and receiving schemes of UWB system. Literature survey given in this paper, gives brief idea on the techniques whi...

A UWB impulse array antenna (IAA) utilizing a novel electrical scanning system with tapped delay lines is proposed and its usefulness is experimentally verified. The experimental antenna is composed of impulse generators installed in each antenna element and tapped delay lines used for creating transmitting trigger signals, which is a simple circuit configuration. It is shown that the output ph...

In this paper we present a low power temporaldifference image sensor with wireless communication capability designed specifically for imaging sensor networks. The eventbased image sensor features a 64×64 pixel array and can also report standard analog intensity images. An ultra-wideband (UWB) radio channel allows to transmit digital temporal difference images wirelessly to a receiver with high ...

This paper evaluates the level of interference caused by different ultra-wideband (UWB) signals to other various radio systems, as well as the performance degradation of UWB systems in the presence of narrowband interference and pulsed jamming. The in-band interference caused by a selection of UWB signals is calculated at GSM900, UMTS/wideband code-division multiple-access (WCDMA), and global p...

Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) approach using UWB signals with short duration of pulses provide unique advantages in short-range high data rate wireless applications which include easy penetration through obstacles, high precision ranging and low processing power. In this paper a performance study on MB-OFDM is attempted for high data rate ultra wideband (UWB) WP...

This paper presents a tightly-coupled integration of GPS observations and ultra-wideband ranges that accounts for systematic UWB errors in real-time using additional error states to augment an extended Kalman filter. Results of range measurements obtained using commercially available UWB radios in optimal line-of-sight conditions are compared to surveyed ranges using conventional methods to ass...

An ultra-wideband microwave imaging system that employs a heterogeneous breast phantom and covers the ultrawideband (UWB) frequency range (3.1 GHz to 10.6 GHz) is presented. The platform scanning system allows monostatic and bistatic mode of operation. In this work, developed heterogeneous phantoms are used to mimic the realistic breast tissues. A utilized tapered slot antenna array allows for ...