Ultra wideband (UWB) antenna operation close to tissue is examined by using lumpedelement equivalent circuits in the present paper. The impact of tissue within the reactive near-field of the antenna is introduced in terms of efficiency, impedance and matching to 50 Ω. The parasitic components for the seriesand parallel-resonant stages of the equivalent models are proposed for taking the impact ...

In the area of wearable technology an enhancement basic microstrip antenna is evolution textile antenna. A major requirement for its flexible designed materials which incoprates fabric in structure. The parameters obtained from are return loss (S-11), directivity, gain, voltage standing wave ratio (VSWR) as well specific absorption rate (SAR) value. All these mostly influenced by value substrat...

Chaotic signals are ultra-wideband signals that can be generated with simple circuits in any frequency bands at arbitrary power level. The ultra-wideband property of chaotic carriers is beneficial in indoor and mobile applications where multipath propagation limits the attainable bit error rate. Another possible application is the ultra-wideband (UWB) radio, where the spectrum of transmitted si...

Ultra-wideband (UWB) communication techniques have attracted a great interest in both academia and industry in the past few years for applications in short-range wireless mobile systems. This is due to the potential advantages of UWB transmissions such as low power, high rate, immunity to multipath propagation, less complex transceiver hardware, and low interference. In this paper we review com...

Ultra Wideband (UWB) radio system is an emerging wireless radio technology. It can transmit digital data over a wide spectrum of frequency band with very low power. This paper presents an analysis of UWB technology on direct millimeter wave six-port receiver, to be designed as an application-specific integrated receiver using Frequency Diversity Spread Spectrum (FDSS) technique. With wideband s...

After a very short introduction to the history and theory of ultra wideband technology, we describe the current state-of-the-art (within the United States) in this emerging field by way of examples of recently fielded UWB hardware and equipment. Multispectral Solutions, Inc. (MSSI) is a pioneer and an established industry leader in the development of ultra wideband systems and has been actively...

In this paper, a new Ultra Wideband (UWB) channel estimation algorithm, UWB-SAGE (Space Alternating Generalized Expectation Maximization) is proposed. In the algorithm, a novel UWB signal model which is an extention of the conventional wideband signal model is employed in order to estimate the UWB channel with SAGE algorithm. The algorithm divides the measured data into individual ray paths and...

Mobile communication have become an important part of telecommunications. Original applications like paging, mobile phones or GPS have shown a tremendous growth, and new applications are emerging every day: tagging, wireless computer links, wireless microphones, remote control, wireless multimedia links, satellite mobile phones, wireless internet. Mobile means light, small, with low energy cons...

Ultra-wideband (UWB) radio is a fast emerging technology with uniquely attractive features inviting major advances in wireless communications, networking, radar, imaging, and positioning systems. UWB radios offer great flexibility and shows enormous potential in view of future fourth generation (4G) broadband wireless access in dense multipath environments. In this paper jointly PHY and MAC lay...

In this paper, the suitabilities of direct sequence ultra wideband (DS-UWB) and ultra wideband frequency modulation (UWB-FM) are studied for medical applications. The system performances are studied by applying the measured hospital channels. The channel measurements were done at the Oulu University hospital in 2005. The measurement campaign included three different hospital environments, i.e. ...