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For stroke detection, low frequencies are required due to the increasing signal attenuation in human tissues with the frequency. In this paper a multiband slotted Bowtie antenna is proposed, which can be operated directly on or near to the skin. The antenna has a very small size of 26×34 mm2. Moreover, the operating bands are from 0.5 to 0.7 GHz and 1.3 to 4 GHz. The antenna is optimized in the simulation...
This paper discusses the pulse distortion of two-arm spiral antennas in ultra-wideband (UWB) communication links and mitigation thereof by modifying the antenna so that phase and amplitude distortions are accounted for by the aperture itself. A new spiral topology, named power-spiral, is introduced to reduce the effect of the phase distortions. When combined with classical Archimedean spiral, this...
An important prerequisite for precision localization is to discern "direct paths" (DP), i.e., paths that suffer a single reflection process on their way from the transmitter to the receiver, from indirect paths (IPs). This paper studies how to distinguish between DPs and IPs purely based on measurements of radio propagation parameters, namely the time of arrival (TOA), direction of departure...
The use of UWB imaging for bone cancer is described. A UWB monopole antenna in the 1–10 GHz range is used to scan a three layer model of bone, muscle, bone cortex and marrow, with and without a tumor. Using image reconstruction techniques, the results for the detection of the tumor and for an estimation of the tumor size are presented. Tumors of a radius from 8 to 30 mm and at a depth from 2 to 31...
Design of miniaturized wideband filter in combline configuration using interresonator taps and interdigitally-coupled capacitive loading is described. The design is based on increasing the effective capacitance of the original quarter-wavelength combline resonator by engineering the loading interdigital capacitance at the open end of resonator, thus achieving the same resonant frequency by using a...
This paper discusses coexisting signal detection technique of the interference DAA (Detect And Avoid) operation. In this paper, the emission of the coexisting singles and their occupied frequency band detection technique for the MB-OFDM (Multi-Band OFDM) system is proposed in order to improve the DER (miss Detection Error Rate) and the FAR (False Alarm Rate). The received coexisting signal is assumed...
This paper provides a historical overview of ultrawideband (UWB) antennas. Early radio was narrowband in conception, but UWB in practice due to various technical limitations. Oliver Lodge pioneered UWB antenna engineering in the nineteenth century with his invention of both the biconical and bowtie antennas, and J.C. Bose demonstrated the first horn antennas in 1897. These nineteenth century spark-gap...
Remote sensing of body and inner organ motion by ultra-wideband radar is a promising alternative to electrocardiogram (ECG) based gating of several diagnostic imaging and image guided therapy modalities, e.g. cardiac magnetic resonance imaging (MRI) and high energy particle therapy. In this paper, we present a noncontact approach for the detection of cardiac mechanics by means of multi-channel UWB...
In multipath assisted indoor navigation and tracking (MINT), individual multipath components (MPCs) of the ultra wideband (UWB) channel needs to be extracted. A sequential Monte-Carlo based implementation of the multi-source multitarget probability hypothesis density (PHD) filter is used in order to jointly estimate the number of multipath components present as well as their individual parameters...
The article deals with SiGe based hardware for new, flexible ultra-wideband MIMO sensing purposes using pn-sequence approach. Introduced hardware serves as future platform for scientific investigations in the complex field of ultrawideband (UWB) applications. We discuss the design aspects and prototype evaluation of the single chip M-sequence based sensor head as well as realization particularities...
UWB has been a very attractive choice for medical radar and localization applications. The use of UWB signals can provide distance measurements with very high accuracy but a big challenge is caused by high attenuation resulting in low signal-to-noise ratios. It is well-known that analog-to-digital conversion is practically not feasible for UWB. Compressed Sensing is an emerging concept which potentially...
Impulse radio ultra wideband (IR UWB) is a promising technology for positioning. Many papers about UWB positioning focus on cooperative target. The study considers UWB positioning for noncooperative target, which means that the target is passive and does not transmit signal. There are few papers in the literature on the field. Existing papers place great emphasis on positioning algorithms instead...
Imaging by microwave UWB radar represents a promising technique for early-stage breast cancer detection. We present an experimental measurement setup for breast phantom trials based on M-sequence radar technology and active small antennas (interfacial dipoles). This approach combines short impulse responses, sufficient fidelity and very small antenna dimensions and allows for array construction with...
In this article we give an overview about the principles of polarimetric Ultrawideband Radar. Starting from the state of the art and a summary of the theory we analyze the calibration principles of polarized UWB Radar Data, we investigate possible imaging algorithms and we list important applications. Finally we show an example, to detect certain targets using a polarimetric MIMO UWB radar by doing...
This paper investigates the performance of high data rate coexistence-based channel coding within a noncoherent Multiband Impulse Radio UWB system. It is shown that in the presence of interference the combination of adaptive image-based thresholding and channel coding can lead to a significant performance gain in comparison to thresholding-only. For thresholding two low complex methods, the Otsu algorithm...
Main objective of this contribution is to apply Interference Alignment (IA) algorithms in real-world indoor environments for UWB MIMO MB-OFDM communication systems. In indoor environments, the required orthogonality between multiusers channels, which is necessary for proper IA, could be hardly reached. The spatial diversity among the users/nodes is mostly insufficient to obtain a robust performance...
An ultra-wide band pulse transceiver has been developed using integrated circuits which demonstrates a tunable 10dB bandwidth from 1.4 GHz to 3.3 GHz. The transceiver has a synchronous receiver which demodulates and extends the pulse in time using Equivalent Time Sampling (ETS) techniques. Equivalent time sampling has been shown to accurately reconstruct the RF pulse with an ETS factor up to 1.5 million...
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