Wall Compensation for Ultra Wideband Applications

Due to their low frequency contents, ultra wideband (UWB) signals have the ability to penetrate walls and obstacles. As the signal propagates through these obstacles, it gets attenuated, slows down, and gets dispersed. This paper demonstrates wall compensation for through-wall imaging, localization and communication receiver design purposes by first characterizing wave propagation through various building materials in the UWB frequency range. Knowledge of the walls obtained from the wall characterization is used to estimate and correct the position accuracy of a target object located behind the walls using three proposed methods namely; constant amplitude and delay (CDL), frequency dependent data (FFD), and data fitting methods (FIT). The obtained results indicated relatively acceptable measure of wall compensation for the three methods. Results from such work provide insight on how to develop algorithms for effective target position estimation in imaging and localization applications. They are also useful for channel modelling and link budget analysis

Fork-Coupled Resonators for High-Frequency Characterization of Dielectric Substrate Materials

Efficient coupling of energy in and out of a resonator can significantly enhance its performance, particularly when used for dielectric characterization of materials. In this paper, a new microstrip resonator is introduced, which uses fork-shaped feed elements for improving the coupling efficiency. The proposed resonator is studied both experimentally and theoretically with field simulation software. An important advantage of the fork microstrip resonator is attributed to its single-layer geometry and easier manufacturing processes. This resonator is used to characterize three different dielectric materials. Comparison of measurement results from the fork resonator with those obtained with a stripline resonator suggests that the proposed resonator offers a superior performanc

Fork-Coupled Resonators for High-Frequency Characterization of Dielectric Substrate Materials

Efficient coupling of energy in and out of a resonator can significantly enhance its performance, particularly when used for dielectric characterization of materials. In this paper, a new microstrip resonator is introduced, which uses fork-shaped feed elements for improving the coupling efficiency. The proposed resonator is studied both experimentally and theoretically with field simulation software. An important advantage of the fork microstrip resonator is attributed to its single-layer geometry and easier manufacturing processes. This resonator is used to characterize three different dielectric materials. Comparison of measurement results from the fork resonator with those obtained with a stripline resonator suggests that the proposed resonator offers a superior performanc

UWB Multipath Simulator based on TEM Horn Antenna

Most of the existing UWB models are extensions of narrowband models. These models suffer from limitations because UWB multipath propagation is frequency and antenna dependent. In this paper, a directional simulator based on TEM horn antenna is developed. This simulator illustrates the spatial impact on the received multipath profiles. Several deterministic scenarios are simulated to examine the antenna impact on receiver design and positioning accuracy

UWB Multipath Simulator based on TEM Horn Antenna

Most of the existing UWB models are extensions of narrowband models. These models suffer from limitations because UWB multipath propagation is frequency and antenna dependent. In this paper, a directional simulator based on TEM horn antenna is developed. This simulator illustrates the spatial impact on the received multipath profiles. Several deterministic scenarios are simulated to examine the antenna impact on receiver design and positioning accuracy

On the Positioning Capability of UWB Systems

A time-domain measurement experiment that illustrates the positioning capability of ultra wideband (UWB) systems is illustrated. Both measurement setup and measurement locations are detailed. The paper highlights the challenges that limit the utilization of the high precision of UWB systems. These challenges include multipath, pulse dispersion, and the antenna effect on the pulse-shape due to angles of transmission and arrival