scholarly journals A compact and miniaturized implantable antenna for ISM band in wireless cardiac pacemaker system

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Yang Feng ◽  
Zhaonan Li ◽  
Lin Qi ◽  
Wanting Shen ◽  
Gaosheng Li
Keyword(s):  
Frequency Band ◽  
Specific Absorption Rate ◽  
High Dielectric Constant ◽  
Impedance Matching ◽  
Cardiac Pacemaker ◽  
Actual Measurement ◽  
Implantable Antenna ◽  
Overall Performance ◽  
High Dielectric ◽  
Peak Gain

AbstractA tiny and compact implantable antenna for wireless cardiac pacemaker systems is designed. The antenna works in the Industrial Scientific Medical (ISM) frequency band (2.4–2.48 GHz). The size of the antenna is greatly reduced with the adoption of a high dielectric constant medium and a folded meander structure. The volume of the antenna is 4.5 mm3, and the size is only 3 mm × 3 mm × 0.5 mm. Based on the literature research, it was found that the design was the smallest among the same type of implanted antenna. The antenna is optimized and loaded with a defective slotted structure, which improves the efficiency of the overall performance of the antenna and thus the gain thereof. The antenna maintains good impedance matching in the ISM frequency band, covering the entire ISM frequency band. The actual bandwidth of the antenna is 22%, with the peak gain of − 24.9 dBi. The antenna is processed and manufactured in such a manner that the simulation keeps consistent with the actual measurement. In addition, the specific absorption rate of the antenna is also evaluated and analyzed. The result shows that this kind of antenna is the best choice to realize the wireless biological telemetry communication in the extremely compact space of the wireless cardiac pacemaker system.

Fe3O4-decorated single-walled carbon nanohorns with extraordinary microwave absorption property

RSC Advances ◽  
2015 ◽  
Vol 5 (92) ◽  
pp. 75817-75822 ◽  
Author(s):  
Longbin Cui ◽  
Yang Liu ◽  
Xiaohui Wu ◽  
Ziqi Hu ◽  
Zujin Shi ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Microwave Absorption ◽  
High Dielectric Constant ◽  
Impedance Matching ◽  
Microwave Absorption Property ◽  
Absorption Property ◽  
Carbon Nanohorns ◽  
Single Walled Carbon ◽  
Wave Absorption ◽  
High Dielectric

Single-walled carbon nanohorns (SWCNHs) are seldom used as electromagnetic (EM) wave absorption materials due to their inferior impedance matching resulting from their high dielectric constant.

scholarly journals Omega-Shaped Tag Antenna with Inductively-Coupled Feeding Using U-Shaped Stepped-Impedance Resonators for RFID Applications

2020 ◽  
Vol 35 (8) ◽  
pp. 951-961
Author(s):  
Adam Alhawari ◽  
Abdulkarem Almawgani ◽  
Hisham Alghamdi ◽  
Ayman Hindi ◽  
Tale Saeidi ◽  
...  
Keyword(s):  
Radio Frequency Identification ◽  
Impedance Matching ◽  
Feeding Method ◽  
Rfid Tag ◽  
Inductively Coupled ◽  
Feeding Technique ◽  
Frequency Identification ◽  
Overall Performance ◽  
Rfid Applications ◽  
Peak Gain

This study proposes a new omega-shaped tag antenna with inductively-coupled feeding (ICF) using U-shaped stepped- impedance resonators (SIRs). It aims at improving the performance of the tag antennas for Radio Frequency Identification (RFID) applications. The radiating body of the antenna is fed using two mirroring symmetrical U-shaped SIRs. This antenna is a simpler alternative for the existing antennas that match the impedance of the antenna to the chip impedance effectively applying varied reinforcement of the equivalent inductance of the radiating structure. In addition to the use of an omega-shaped structure, the proposed feeding technique boosts performance of the antenna impedance, dimensions, and peak gain. The measured size of the antenna was 50×55.55×1.6 mm3. It attains a peak gain of 1.8 dBi and radiation efficiency higher than 85% at its operating frequency. The experimental results revealed that this tag antenna has the characteristic of good impedance matching within the frequency range of 900-940 MHz, corresponding to a better power reflection coefficient of -3 dB. Comparison between the measured and simulated results verified that the proposed feeding method is capable to improve overall performance of RFID tag antennas.

SAR analysis of tri-band antennas for a 5G eyewear device

2020 ◽  
Vol 12 (8) ◽  
pp. 754-761
Author(s):  
M. Dilruba Geyikoğlu ◽  
Hilal Koç Polat ◽  
Fatih Kaburcuk ◽  
Bülent Çavuşoğlu
Keyword(s):  
Absorption Rate ◽  
Specific Absorption Rate ◽  
High Dielectric Constant ◽  
Human Head ◽  
3D Printer ◽  
Dipole Antennas ◽  
Device Applications ◽  
Simulation Results ◽  
High Dielectric ◽  
Sar Analysis

AbstractThe goal of this study is to analyze the specific absorption rate (SAR) distribution of the projected 5G frequencies below 6 GHz and at Wi-Fi frequency (2.45 GHz) on a human head, for eyewear device applications. Two separate tri-band printed dipole antennas for this purpose are designed and fabricated at operating frequencies of 2.45/3.8/6 GHz for prototype-1 and at operating frequencies of 2.45/3.6/4.56 GHz for prototype-2. In order to obtain the desired frequencies: first, the prototypes of the proposed antennas are fine-tuned via Computer Simulation Technology Microwave Studio (CST) and then fabricated on the FR4 layer. The reflection coefficient (S11) is tested and the simulation results are confirmed. In order to analyze the effect of wearing a pair of glasses' frame including a tri-band 5G antenna, a frame is designed and produced via 3D printer with polylactic acid material which has high dielectric constant (ɛr = 8.1). The SAR results of the proposed antennas have been examined for the cases where the antenna is embedded in the frame and is used alone. Both cases were analyzed by using the homogeneous specific anthropomorphic mannequin and the heterogeneous visible human head phantoms and the results have been evaluated in terms of SAR10 g values.

Enhanced performance of supercapacitors by constructing a “mini parallel-plate capacitor” in an electrode with high dielectric constant materials

2020 ◽  
Vol 8 (32) ◽  
pp. 16661-16668
Author(s):  
Huayao Tu ◽  
Shouzhi Wang ◽  
Hehe Jiang ◽  
Zhenyan Liang ◽  
Dong Shi ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Carbon Fiber ◽  
Parallel Plate ◽  
Sandwich Structure ◽  
High Dielectric Constant ◽  
Parallel Plate Capacitor ◽  
Plate Capacitor ◽  
Fiber Metal ◽  
High Dielectric ◽  
Mini Plate

The carbon fiber/metal oxide/metal oxynitride layer sandwich structure is constructed in the electrode to form a mini-plate capacitor. High dielectric constant metal oxides act as dielectric to increase their capacitance.

Skin–core structured fluorinated MWCNTs: a nanofiller towards a broadband dielectric material with a high dielectric constant and low dielectric loss

2018 ◽  
Vol 6 (9) ◽  
pp. 2370-2378 ◽  
Author(s):  
Yang Liu ◽  
Cheng Zhang ◽  
Benyuan Huang ◽  
Xu Wang ◽  
Yulong Li ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
High Dielectric Constant ◽  
Dielectric Material ◽  
Epoxy Composite ◽  
Low Dielectric ◽  
High Dielectric

A novel skin–core structured fluorinated MWCNT nanofiller was prepared to fabricate epoxy composite with broadband high dielectric constant and low dielectric loss.

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