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Coaxial resonant cavity for measuring complex permittivity of liquids 测量液体复介电常数的同轴谐振腔
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-09-26 DOI: 10.1515/freq-2022-0115
Yi Wang, Zhixia Xu, Yulin Feng, Shaojun Fang
{"title":"Coaxial resonant cavity for measuring complex permittivity of liquids","authors":"Yi Wang, Zhixia Xu, Yulin Feng, Shaojun Fang","doi":"10.1515/freq-2022-0115","DOIUrl":"https://doi.org/10.1515/freq-2022-0115","url":null,"abstract":"Abstract In this letter, a new microwave sensor of the coaxial resonant cavity with a single-open-ended circuit loaded capacitor is proposed and used to detect the liquids’ complex permittivity. The improved cavity has a higher internal electric field and smaller size when compared with the cylindrical cavity, which gives the sensor a high sensitivity in measuring liquids’ complex permittivity. A coaxial resonant cavity operating in 1.9 GHz was designed in this work. The silicone hose used for the test is inserted vertically from the center of the cavity, and the liquids under test (LUTs) are guaranteed to be 2 ml each time. The dielectric properties of LUTs will cause perturbation to the internal electric field of the cavity. By analyzing the measured data, the sensitivity of the cavity is 0.12%, and the relative errors of the real part of the measured value and the reference value are 3.67%. which shows the measured value has a good agreement with the reference value.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"229 - 234"},"PeriodicalIF":1.1,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47992403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
A compact breath gas sensor system based on terahertz/millimeter-wave gas spectroscopy 基于太赫兹/毫米波气体光谱的紧凑型呼吸气体传感器系统
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-09-26 DOI: 10.1515/freq-2022-0131
N. Rothbart, K. Schmalz, R. Koczulla, H. Hübers
{"title":"A compact breath gas sensor system based on terahertz/millimeter-wave gas spectroscopy","authors":"N. Rothbart, K. Schmalz, R. Koczulla, H. Hübers","doi":"10.1515/freq-2022-0131","DOIUrl":"https://doi.org/10.1515/freq-2022-0131","url":null,"abstract":"Abstract We demonstrate a full-cycle breath gas sensor system based on terahertz/millimeter-wave gas spectroscopy. The sensor consists of a transmitter and receiver working around 250 GHz based on SiGe BiCMOS technology. Typical detection thresholds are in the ppm range depending on the respective molecule. The data analysis provides partial pressures of the investigated molecules by fitting of spectra which are measured by wavelength modulation. Beside the spectroscopic measurement and the data analysis, a full cycle of breath analysis includes the sampling and the conditioning of the sample tubes. The full cycle takes about 35 min per sample in average. As the system is compact and easy to operate, it allows for on-site analysis of breath samples in medical laboratories or hospitals.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"76 1","pages":"669 - 676"},"PeriodicalIF":1.1,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46079692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Towards single-cell pulsed EPR using VCO-based EPR-on-a-chip detectors 利用基于vco的EPR芯片探测器实现单细胞脉冲EPR
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-09-16 DOI: 10.1515/freq-2022-0096
Mohamed Atef Hassan, M. Kern, Anh Chu, Gatik Kalra, E. Shabratova, Aleksei Tsarapkin, Neil MacKinnon, K. Lips, C. Teutloff, R. Bittl, J. Korvink, J. Anders
{"title":"Towards single-cell pulsed EPR using VCO-based EPR-on-a-chip detectors","authors":"Mohamed Atef Hassan, M. Kern, Anh Chu, Gatik Kalra, E. Shabratova, Aleksei Tsarapkin, Neil MacKinnon, K. Lips, C. Teutloff, R. Bittl, J. Korvink, J. Anders","doi":"10.1515/freq-2022-0096","DOIUrl":"https://doi.org/10.1515/freq-2022-0096","url":null,"abstract":"Abstract Electron paramagnetic resonance (EPR) is the gold standard for studying paramagnetic species. As an example, in structural biology, it allows to extract information about distance distributions on the nanometer scale via site-directed spin labeling. Conventional pulsed EPR of biological samples is currently limited to relatively large sample concentrations and cryogenic temperatures, mainly due to low sensitivity and the significant dead time associated with conventional resonator-based EPR setups, essentially precluding in-cell EPR under physiological conditions. This paper presents our latest progress toward single-cell pulsed EPR using VCO-based EPR-on-a-chip (EPRoC) sensors. Together with an analytical model for VCO-based pulsed EPR, we present an experimental scheme to perform dead-time-free pulsed EPR measurements using EPRoC detectors. The proposed scheme is validated using extensive numerical simulations and proof-of-concept experiments on the spin dynamics of an organic radical at room temperature using a custom-designed EPRoC detector operating in the Ka-band around 30.4 GHz. Additionally, we discuss methods to improve the excitation field homogeneity and sample handling through chip post-processing and custom-designed microfluidics. Finally, we present our progress towards compact, portable pulsed EPR spectrometers incorporating EPRoC detectors, microfluidics, and custom-designed permanent magnets. Such portable EPR spectrometers can pave the way toward new EPR applications, including point-of-care diagnostics.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"76 1","pages":"699 - 717"},"PeriodicalIF":1.1,"publicationDate":"2022-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44773499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
A miniaturized quad band hexagon patch antenna for GSM1800, C band and WiMAX applications 用于GSM1800、C波段和WiMAX应用的小型化四频带六边形贴片天线
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-29 DOI: 10.1515/freq-2022-0046
F. Mouhouche, K. Djafri, M. Dehmas, Kahina Chibane, Safa Ksentini
{"title":"A miniaturized quad band hexagon patch antenna for GSM1800, C band and WiMAX applications","authors":"F. Mouhouche, K. Djafri, M. Dehmas, Kahina Chibane, Safa Ksentini","doi":"10.1515/freq-2022-0046","DOIUrl":"https://doi.org/10.1515/freq-2022-0046","url":null,"abstract":"Abstract In this article, a miniaturized patch antenna using fractal DGS and SRR DMS for GSM1800, C band and WiMAX applications is presented and investigated. Antenna miniaturization and multiband are accomplished by employing a fractal loop on the DGS structure and a split ring resonator slot in the patch. The proposed radiator has a hexagonal shape that operates at 6.8 GHz. To achieve downsize of 20.58, 38.22, 55.14 and 72.75% an antenna is designed using DGS and DMS structures for quad-band application appearing at 1.85, 3.05, 4.2, and 5.4 GHz. Simulated and tested data are investigated. The prototype antenna has adequate advantages, with a simple structure, compact size, multiband, and uniform radiation patterns.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"203 - 210"},"PeriodicalIF":1.1,"publicationDate":"2022-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48107157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Circular shape monopole antenna with modified ground plane proclaiming SWB characteristics 圆形单极天线与改进的地平面宣布SWB特性
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-26 DOI: 10.1515/freq-2022-0087
Ranjeet Kumar, R. Sinha, A. Choubey, S. K. Mahto
{"title":"Circular shape monopole antenna with modified ground plane proclaiming SWB characteristics","authors":"Ranjeet Kumar, R. Sinha, A. Choubey, S. K. Mahto","doi":"10.1515/freq-2022-0087","DOIUrl":"https://doi.org/10.1515/freq-2022-0087","url":null,"abstract":"Abstract Modern communication systems require an antenna with miniaturized size and large bandwidth with high data rate. In this article, a circular monopole antenna is presented with hexagonal patch on both sides of microstrip feedline and an I- shaped rectangular slot etched at the center of feedline to provide impedance matching. The modified loaded ground reduces the coupling between ground plane and radiation patch. This antenna has compact dimension of 30 mm × 25 mm with electrical size of 0.25λ × 0.20λ. This antenna has been designed and simulated in HFSS commercial software and fabricated on FR4 substrate of thickness 1.6 mm with relative permittivity 4.4, loss tangent of 0.02. The experimental results are compared with simulated one, which are in close agreement. It attains a frequency band ranging from 2.4 to 56.6 GHz with reflection coefficient <−10, percentage bandwidth of 183.72%, Bandwidth Ratio (BR) 23.58:1, and Bandwidth Dimension Ratio (BDR) of 3674.40. The peak gain and radiation efficiency of this antenna is 12.77 dBi and 98.82% at 45.84 and 5.6 GHz respectively. Time domain analysis has been done, which proclaims that the proposed antenna has SWB characteristics. It may be useful for high data rate transmission, medical imaging, and other SWB applications.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"303 - 313"},"PeriodicalIF":1.1,"publicationDate":"2022-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48761982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Compact quadband two-port antenna with metamaterial cell-inspired decoupling parasitic element for mobile wireless applications 紧凑型四频双端口天线，具有超材料蜂窝启发的去耦寄生元件，用于移动无线应用
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-25 DOI: 10.1515/freq-2021-0299
Pierre Moukala Mpele, Franck Moukanda Mbango, D. Konditi, Ce Lakpo Bamy, Felix Urimubenshi
{"title":"Compact quadband two-port antenna with metamaterial cell-inspired decoupling parasitic element for mobile wireless applications","authors":"Pierre Moukala Mpele, Franck Moukanda Mbango, D. Konditi, Ce Lakpo Bamy, Felix Urimubenshi","doi":"10.1515/freq-2021-0299","DOIUrl":"https://doi.org/10.1515/freq-2021-0299","url":null,"abstract":"Abstract In this paper, a quadband MIMO diamond-shaped antenna with two highly isolated elements is proposed and discussed. A novel metamaterial cell-inspired decoupling parasitic structure is deployed between the two antenna elements to achieve high isolation greater than 20 dB in the frequency bands of interest. Moreover, the design adopts a defected ground structure and open-ended multiple diamond-shaped branches for multiband characteristics, enabling the proposed MIMO to cover several modern wireless applications. The performance metrics of the proposed MIMO antenna are validated by evaluating various diversity parameters such as envelope correlation coefficient (ECC), diversity gain (DG), total active reflection coefficient (TARC), and channel capacity loss (CCL). This antenna is fabricated on an FR4 substrate with a compact size of 12 × 30 × 1.524 mm (0.082λ0 × 0.204λ0 × 0.001λ0, λ0 is the wavelength at 2.04 GHz). With the edge-to-edge separation distance of 0.053λ0 between the antenna elements, its prototype is experimentally measured using a two-port Rohde & Schwarz ZVA50 Vector Network Analyzer. The port-to-port isolation is about −20.87 dB, −23 dB, −25.93 dB, and −25.22 dB for 2.3 GHz, 3.18 GHz, 4.08 GHz, and 5.42 GHz frequency bands, respectively. Also, the proposed MIMO antenna exhibits good diversity performances with the ECC < 0.005, DG > 9.99, and TARC<−10 dB making it an outstanding candidate covering 4G/LTE, 5G NR sub-6 GHz n40/n41/n77/n78, Wi-Fi, WiMAX, ISM, WBAN, Bluetooth, MBAN, WiBro, C-V2X, and UWB applications.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"63 - 76"},"PeriodicalIF":1.1,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48137097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Design and fabrication of an ultra compact Gysel power divider with harmonic suppression by using U shaped resonators U型谐振腔抑制谐波的超小型Gysel功率分配器的设计与制造
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-23 DOI: 10.1515/freq-2021-0207
Maryam Shirzadian Gilan, Farhad Gholami
{"title":"Design and fabrication of an ultra compact Gysel power divider with harmonic suppression by using U shaped resonators","authors":"Maryam Shirzadian Gilan, Farhad Gholami","doi":"10.1515/freq-2021-0207","DOIUrl":"https://doi.org/10.1515/freq-2021-0207","url":null,"abstract":"Abstract In this paper, a new design of Gysel power divider with good performance and very compact size is presented. In this design, rectangular resonators and U shaped transmission lines are used. Operating frequency that is considered is 580 MHZ. The proposed power divider only takes 15.83% of the area of the corresponding conventional Gysel power divider. Proposed equal low pass filters are replaced with transmission lines and the harmonics suppression is also improved. In this design, 10 harmonics are suppressed. Finally, the proposed power divider is fabricated and a good match is found between the simulation and measurement results.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"23 - 27"},"PeriodicalIF":1.1,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47114150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Evolution of a theranostic applicator for microwave ablation treatment 用于微波消融治疗的治疗探头的发展
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-17 DOI: 10.1515/freq-2022-0088
Carolin Hessinger, F. Hübner, M. Schüßler, M. Paravicini, Markus Ketomäki, T. Vogl, R. Jakoby
{"title":"Evolution of a theranostic applicator for microwave ablation treatment","authors":"Carolin Hessinger, F. Hübner, M. Schüßler, M. Paravicini, Markus Ketomäki, T. Vogl, R. Jakoby","doi":"10.1515/freq-2022-0088","DOIUrl":"https://doi.org/10.1515/freq-2022-0088","url":null,"abstract":"Abstract The purpose of this work is to further develop a novel dual-mode microwave applicator for diagnosis and thermal ablation treatment. The MR-compatible MW applicator enables differentiation of tumor tissue and healthy tissue through dielectric contrast measurements, optimizing the positioning of the applicator in the lesion. Due to the robust applicator design and the resulting permittivity tracking during ablation, even carbonized tissue can be detected. The use of operating frequencies between 5 and 10 GHz allow a noticeably lower power consumption for microwave ablation of only 20 W compared to commercially available applicators. Clinically relevant dimensions of ablation zones can be achieved and additionally monitored using MR imaging and thermometry.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"76 1","pages":"677 - 684"},"PeriodicalIF":1.1,"publicationDate":"2022-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49112268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Terahertz subwavelength sensing with bio-functionalized germanium fano-resonators 生物功能化锗共振器的太赫兹亚波长传感
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-15 DOI: 10.1515/freq-2022-0078
C. Chavarin, E. Hardt, O. Skibitzki, T. Voß, Mohammed Eissa, Davide Spirito, G. Capellini, L. Baldassarre, J. Flesch, J. Piehler, C. You, Sönke Grüssing, F. Römer, B. Witzigmann
{"title":"Terahertz subwavelength sensing with bio-functionalized germanium fano-resonators","authors":"C. Chavarin, E. Hardt, O. Skibitzki, T. Voß, Mohammed Eissa, Davide Spirito, G. Capellini, L. Baldassarre, J. Flesch, J. Piehler, C. You, Sönke Grüssing, F. Römer, B. Witzigmann","doi":"10.1515/freq-2022-0078","DOIUrl":"https://doi.org/10.1515/freq-2022-0078","url":null,"abstract":"Abstract Localized Surface Plasmon Resonances (LSPR) based on highly doped semiconductors microstructures, such as antennas, can be engineered to exhibit resonant features at THz frequencies. In this work, we demonstrate plasmonic antennas with increased quality factor LSPRs from Fano coupling to dark modes. We also discuss the advances in the biofunctionalization of n-doped Ge antennas for specific protein immobilization and cell interfacing. Finally, albumin biolayers with a thickness of a few hundred nanometers are used to demonstrate the performance of the fano-coupled n-Ge antennas as sensors. A resonant change of over 10% in transmission, due to the presence of the biolayer, can be detected within a bandwidth of only 20 GHz.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"76 1","pages":"639 - 650"},"PeriodicalIF":1.1,"publicationDate":"2022-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43270961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A novel miniaturized V-shaped monopole antenna for GSM/WiMAX/WLAN applications 一种适用于GSM/WiMAX/WLAN应用的新型小型V形单极天线
IF 1.1 4区 工程技术
Frequenz Pub Date : 2022-08-15 DOI: 10.1515/freq-2022-0061
K. Fertas, F. Fertas, M. Challal, T. Denidni
{"title":"A novel miniaturized V-shaped monopole antenna for GSM/WiMAX/WLAN applications","authors":"K. Fertas, F. Fertas, M. Challal, T. Denidni","doi":"10.1515/freq-2022-0061","DOIUrl":"https://doi.org/10.1515/freq-2022-0061","url":null,"abstract":"Abstract This paper presents a novel miniaturized triple band V-shaped antenna (VSA). The miniaturization and the triple-band operation are obtained by performing two V-shaped turns on the metallic strip. The proposed antenna is printed on a single FR4 substrate and fed using the coplanar waveguide (CPW) technique. It operates in three frequency bands, [1.6–1.95 GHz], [2.8–4.4 GHz] and [5.4–5.8 GHz], with stable bidirectional radiation patterns in both E- and H-planes. A prototype of the designed antenna is fabricated and tested where the observed good agreement between simulated and experimental results indicates that the proposed structure, having a reasonably compact size of 0 . 0166 λ 0 2 $text{0}{text{.}0166lambda }_{0}^{2}$ , is suitable for GSM [1800 MHz], WiMAX [3.4–3.77 GHz] and WLAN [5.725–5.825 GHz] applications.","PeriodicalId":55143,"journal":{"name":"Frequenz","volume":"77 1","pages":"155 - 162"},"PeriodicalIF":1.1,"publicationDate":"2022-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45881608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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