1-Tx/5-Rx Through-Wall UWB Switched-Antenna-Array Radar for Detecting Stationary Humans

This research proposes a through-wall S-band ultra-wideband (UWB) switched-antenna-array radar scheme for detection of stationary human subjects from respiration. The proposed antenna-array radar consists of one transmitting (Tx) and five receiving antennas (Rx). The Tx and Rx antennas are of Vivaldi type with high antenna gain (10 dBi) and narrow-angle directivity. The S-band frequency (2–4 GHz) is capable of penetrating non-metal solid objects and detecting human respiration behind a solid wall. Under the proposed radar scheme, the reflected signals are algorithmically preprocessed and filtered to remove unwanted signals, and 3D signal array is converted into 2D array using statistical variance. The images are reconstructed using back-projection algorithm prior to Sinc-filtered refinement. To validate the detection performance of the through-wall UWB radar scheme, simulations are carried out and experiments performed with single and multiple real stationary human subjects and a mannequin behind the concrete wall. Although the proposed method is an odd concept, the interest of this paper is applying the 1-Tx/5-Rx UWB switched-antenna array radar with the proposed method that is capable of distinguishing between the human subjects and the mannequin behind the concrete wall.

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Human Respiration Localization Method Using UWB Linear Antenna Array

Journal of Sensors ◽

10.1155/2015/601926 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Yuan Liu ◽

Shiyou Wu ◽

Jie Chen ◽

Guangyou Fang ◽

Hejun Yin

Keyword(s):

Antenna Array ◽

Vital Sign ◽

Ultra Wideband ◽

Linear Antenna ◽

Angle Of Arrival ◽

Localization Method ◽

Linear Antenna Array ◽

Human Respiration ◽

Simulation And Experiment ◽

The Individual

Human respiration is the basic vital sign in remote monitoring. There has been remarkable progress in this area, but some challenges still remain to obtain the angle-of-arrival (AOA) and distinguish the individual signals. This paper presents a 2D noncontact human respiration localization method using Ultra-Wideband (UWB) 1D linear antenna array. The imaging reconstruction based on beamforming is used to estimate the AOA of the human chest. The distance-slow time 2D matrix at the estimated AOA is processed to obtain the distance and respiration frequency of the vital sign. The proposed method can be used to isolate signals from individual targets when more than one human object is located in the surveillance space. The feasibility of the proposed method is demonstrated via the simulation and experiment results.

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Random-Noise Denoising and Clutter Elimination of Human Respiration Movements Based on an Improved Time Window Selection Algorithm Using Wavelet Transform

Sensors ◽

10.3390/s19010095 ◽

2018 ◽

Vol 19 (1) ◽

pp. 95 ◽

Cited By ~ 6

Author(s):

Farnaz Shikhsarmast ◽

Tingting Lyu ◽

Xiaolin Liang ◽

Hao Zhang ◽

Thomas Gulliver

Keyword(s):

Time Window ◽

Human Subjects ◽

Wavelet Packet ◽

Random Noise ◽

Vital Signs ◽

Ultra Wideband ◽

Multiple Time ◽

Selection Algorithm ◽

Human Respiration ◽

Window Selection

This paper considers vital signs (VS) such as respiration movement detection of human subjects using an impulse ultra-wideband (UWB) through-wall radar with an improved sensing algorithm for random-noise de-noising and clutter elimination. One filter is used to improve the signal-to-noise ratio (SNR) of these VS signals. Using the wavelet packet decomposition, the standard deviation based spectral kurtosis is employed to analyze the signal characteristics to provide the distance estimate between the radar and human subject. The data size is reduced based on a defined region of interest (ROI), and this improves the system efficiency. The respiration frequency is estimated using a multiple time window selection algorithm. Experimental results are presented which illustrate the efficacy and reliability of this method. The proposed method is shown to provide better VS estimation than existing techniques in the literature.

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Ultra-Wideband Dielectric Lens Antennas for Beamsteering Systems

International Journal of Antennas and Propagation ◽

10.1155/2019/6732758 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Renan Alves dos Santos ◽

Gabriel Lobão da Silva Fré ◽

Luís Gustavo da Silva ◽

Marcelo Carneiro de Paiva ◽

Danilo Henrique Spadoti

Keyword(s):

Antenna Array ◽

Ultra Wideband ◽

Printed Antennas ◽

Lens Antennas ◽

Dielectric Lens ◽

Dielectric Lenses

This paper presents a high-directivity ultra-wideband beamsteering antenna array. An innovative beamsteering system based on hemispherical dielectric lenses fed by a set of different printed antennas is proposed. Diversity of signals in different spatial positions can be radiated at the same time. A prototype was manufactured and characterized, operating in a bandwidth varying from 8 GHz to 12 GHz with gain up to 13 dBi.

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Realizing UWB Antenna Array with Dual and Wide Rejection Bands Using Metamaterial and Electromagnetic Bandgaps Techniques

Micromachines ◽

10.3390/mi12030269 ◽

2021 ◽

Vol 12 (3) ◽

pp. 269

Author(s):

Ayman A. Althuwayb ◽

Mohammad Alibakhshikenari ◽

Bal S. Virdee ◽

Pancham Shukla ◽

Ernesto Limiti

Keyword(s):

Antenna Array ◽

Ground Plane ◽

Ultra Wideband ◽

Dual Band ◽

Area Network ◽

Electromagnetic Bandgap ◽

Uwb Antenna ◽

Average Gain ◽

Left Handed ◽

Notched Band

This research article describes a technique for realizing wideband dual notched functionality in an ultra-wideband (UWB) antenna array based on metamaterial and electromagnetic bandgap (EBG) techniques. For comparison purposes, a reference antenna array was initially designed comprising hexagonal patches that are interconnected to each other. The array was fabricated on standard FR-4 substrate with thickness of 0.8 mm. The reference antenna exhibited an average gain of 1.5 dBi across 5.25–10.1 GHz. To improve the array’s impedance bandwidth for application in UWB systems metamaterial (MTM) characteristics were applied it. This involved embedding hexagonal slots in patch and shorting the patch to the ground-plane with metallic via. This essentially transformed the antenna to a composite right/left-handed structure that behaved like series left-handed capacitance and shunt left-handed inductance. The proposed MTM antenna array now operated over a much wider frequency range (2–12 GHz) with average gain of 5 dBi. Notched band functionality was incorporated in the proposed array to eliminate unwanted interference signals from other wireless communications systems that coexist inside the UWB spectrum. This was achieved by introducing electromagnetic bandgap in the array by etching circular slots on the ground-plane that are aligned underneath each patch and interconnecting microstrip-line in the array. The proposed techniques had no effect on the dimensions of the antenna array (20 mm × 20 mm × 0.87 mm). The results presented confirm dual-band rejection at the wireless local area network (WLAN) band (5.15–5.825 GHz) and X-band satellite downlink communication band (7.10–7.76 GHz). Compared to other dual notched band designs previously published the footprint of the proposed technique is smaller and its rejection notches completely cover the bandwidth of interfering signals.

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1D CNN Based Human Respiration Pattern Recognition using Ultra Wideband Radar

2019 International Conference on Artificial Intelligence in Information and Communication (ICAIIC) ◽

10.1109/icaiic.2019.8669000 ◽

2019 ◽

Cited By ~ 3

Author(s):

Seong-Hoon Kim ◽

Gi-Tae Han

Keyword(s):

Pattern Recognition ◽

Ultra Wideband ◽

Human Respiration ◽

Respiration Pattern ◽

Wideband Radar

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Angle and polarization-independent miniaturized UWB FSS design

International Journal of Microwave and Wireless Technologies ◽

10.1017/s175907872000166x ◽

2021 ◽

pp. 1-9

Author(s):

Yanning Yuan ◽

Yuchen Zhao ◽

Xiaoli Xi

Keyword(s):

Design Method ◽

Incident Angle ◽

Stop Band ◽

Single Layer ◽

Wireless Systems ◽

Frequency Selective Surface ◽

Ultra Wideband ◽

Band Frequency ◽

Gain Enhancement ◽

Polarization Independent

Abstract A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.

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