Due to the low power spectral properties of ultra wideband (UWB) signals, the technology is suitable to be used, e.g., in covert military applications. The open literature lacks of UWB radio channel models that are generated for outdoor use. This paper describes the radio channel measurement campaign carried out to increase the knowledge of the UWB propagation mechanisms in typical Finnish fore...

Non-line-of-sight (NLOS) propagation can severely degrade the reliability of communication and localisation accuracy in indoor ultra-wideband (UWB) ‘location-aware’ networks. Link adaptation and NLOS bias mitigation techniques have respectively been proposed to alleviate these effects, but implicitly rely on the ability to accurately distinguish between LOS and NLOS propagation scenarios. A sta...

A low-cost and portable vector network analyzer (VNA) which covered operating frequency between 1MHz to 3GHz is used for vector reflection coefficient and standing wave ratio (swr) of the various microstrip antennas. This paper presents measurements of various ultra wideband (uwb) microstrip antennas for applications in biomedical field. Selection of antenna is an important key for detection of...

This paper presents the results of a new monopole antenna that exhibits 2.75-10.7 GHz performance. The proposed antenna consists of a radiating patch with notches excited by capacitive coupling feed. Also, the antenna’s truncated ground-plane incorporates a central notch. This modification significantly improves the antenna’s impedance bandwidth by 118% over an ultra-wideband frequency range. T...

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. However, tremendous R&D eff...

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...

Ultra-Wideband Communication is increasingly being considered as an attractive solution for high data rate short range wireless and position location applications. Knowledge of the statistical nature of the channel is necessary to design wireless systems that provide optimum performance. This thesis investigates the spatial characteristics of the channel based on measurements conducted using UW...

The Impulse Radio based Ultra Wideband (IR-UWB) system transmits data by sending pulses, each with very small time duration followed by pauses that are approximately two hundred times that length. Rake receiver improves system performance by equalizing signals from different paths. This enables the use of Rake receiver techniques in UWB systems. For high data rate ultra-wideband communication s...

In this paper, the channel estimation techniques for multiband (MB) OFDM ultra-wideband (UWB) wireless communications are investigated. By combining orthogonal frequency-division multiplexing (OFDM) with multi-band, the MB-OFDM systems can capture multipath energy more efficiently than single-band directsequence UWB (DS-UWB). However, most researches for UWB channel estimation are focused on th...

The successful realization of a Wireless Body Area Network (WBAN) requires innovative solutions to meet the energy consumption budget of the autonomous sensor nodes. The radio interface is a major challenge, since its power consumption must be reduced below 100μW (energy scavenging limit). The emerging Ultra-WideBand (UWB) technology shows strong advantages in reaching this target. First, most ...