This paper introduce the concept of cognitive UWB radio, a wireless system based on UWB transmission able to self adapt to the characteristics of the surrounding environment. UWB is an promising underlying method for coexistence among different systems. However, the performance may not be as good as expected due to the changing spectrum environment. Thus, cognitive UWB radio is proposed by taki...

The ultra wideband (UWB) radio has been a promising technology for the short range wireless systems. The frequencydependent behavior of the antennas are not negligible in UWB systems, especially in the impulse radio (IR). This letter presents the extension of the Friis’ transmission formula for the link budget estimation of UWB radio, considering the transmit signal waveform and the imperfect a...

The next generation of wireless systems is sprouting towards personal area networks. Among them, a very promising application is the Wireless Body Area Network (WBAN) used for health monitoring and ubiquitous computing. Ultra-Wideband (UWB) communication is one of the potential transmission techniques for wireless networks. To optimize receiver structures and antennas for UWB-WBANs with respect...

We study an adaptive transmission approach that exploits the increased phase coherence of ultra-wideband (UWB) channels with a “discrete” number of reflectors relative to narrowband wireless channels. The proposed multipath beamforming technique suggests selecting a ternary or multilevel sequence for an impulsive direct sequence UWB signal waveform based on the signs of the reflection coefficie...

The average age of population is predicted to be raised universally but the number of nursing staff is not increasing at the same rate. This leads us to the situation where, e.g., we have too many patients for one nurse. On the other hand, sparse population in some regions, such as Northern or Eastern Finland, causes a severe problem that doctors are far away from patient. In this paper, we sum...

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We provide an overview of techniques for the photonic generation of arbitrary RF waveforms, particularly those suitable for impulse radio or multi-band ultrawideband (UWB)-over-fiber transmission, and chirped microwave waveforms, with an emphasis on microwave photonic filtering and optical spectral shaping followed by wavelength-to-time mapping. We discuss possibilities for integrating the vari...

The report is devoted to the problem of indoor location using ultrawideband chaotic signals. Two cases are considered. The first corresponds to distance estimation between the transmitter and the receiver. In the second the position of the tag on the plane is determined. Efficiency of proposed systems in comparison with the ultrashort pulses systems is demonstrated. Index terms – Dynamic chaos,...