Communication
Motahareh Arezoomandan; Shahram Mohanna; Ahmad Bakhtiyari Shahri
Abstract
A new compact Ultra-Wide Band (UWB) arch shaped wide-slot antenna has been implemented for Microwave Imaging (MI) of breast cancer. It includes a fork-shaped strip and an arched slot ground, has a compact size of 16×20mm with a height of 1mm. The arched slot in the ground plate enhances the impedance ...
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A new compact Ultra-Wide Band (UWB) arch shaped wide-slot antenna has been implemented for Microwave Imaging (MI) of breast cancer. It includes a fork-shaped strip and an arched slot ground, has a compact size of 16×20mm with a height of 1mm. The arched slot in the ground plate enhances the impedance bandwidth and the gain of the antenna. It has a bandwidth of 3.7 GHz to 18 GHz, that covers WLAN (5.4 GHz), X band (8-12 GHz), and Ku band (12-18 GHz) and having gain of 2.7 dBi to 6.3 dBi in the frequency ranges. The fidelity factor was computed for both E-plane and H-plane scenarios, indicating range of 0.922 to 0.975 for the E-plane across all angles. It has a small size, simple design, less signal distortion, a high gain of 6.3 dBi, the fractional bandwidth percentage of 131%. and efficiency of 93.7% at 6 GHz. It has reliable performances in terms of the fidelity factor at all angles compared to the most recent works. A microwave imaging simulation for breast tumor detection is performed to detect changes in the backscattering signal in the presence or absence of a tumor with a high dielectric inclusion. S11 is quite high when measured in front of the breast model and a noticeable difference in S21 exists between the scenarios with and without a tumor in the breast model. A significant variation in the transmission parameter exists across the entire frequency range, the scenarios with and without the presence of the tumor.
Communication
Fatemeh Geran; Nasim Mirzababaee; Shahram Mohanna
Abstract
An RF energy harvester (rectenna) consists of a broadband monopole antenna and a quad-band rectifying circuit is designed to harvest EM wave energy in the frequency range of 1.412 GHz to 8.56 GHz, which covers GSM-1800, LTE-band, Wimax, Wi-Fi, and WLAN. The initial component of the rectenna is an antenna ...
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An RF energy harvester (rectenna) consists of a broadband monopole antenna and a quad-band rectifying circuit is designed to harvest EM wave energy in the frequency range of 1.412 GHz to 8.56 GHz, which covers GSM-1800, LTE-band, Wimax, Wi-Fi, and WLAN. The initial component of the rectenna is an antenna that includes a semi-circular radiating patch with 8 circular stubs and a semicircle ground plane. The simulation results show the antenna has −10 dB impedance bandwidth at 7.148 GHz (from 1.412 GHz to 8.56 GHz). The second part of the rectenna is a rectifier circuit with a quad-band matching network for RF to DC conversion. The rectifier benefits from a two-stage Dickson rectifier using Schottky diodes. The RF-DC conversion efficiency and output DC voltage are simulated, and the maximum output voltage of the rectifier with the optimum load resistance of R=12 kΩ is 7.2 V, and the peak conversion efficiency is 65.3% when the input power to the rectifier is -4 dBm at 1.71 GHz.
