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Micromachines
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Recent Advances in Microwave Components and Devices
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Recent Advances in Microwave Components and Devices

A special issue of Micromachines (ISSN 2072-666X). This special issue belongs to the section "E：Engineering and Technology".

Deadline for manuscript submissions: closed (20 October 2023) | Viewed by 21010

Special Issue Editors

Dr. Jingchen Wang

E-Mail Website
Guest Editor
Department of Communications and Networking, School of Advanced Technology, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
Interests: microwave circuit design; wireless power transfer and energy harvesting; wearable and implantable antenna design
Special Issues, Collections and Topics in MDPI journals
Dr. Wencheng Lai

E-Mail Website
Guest Editor
Department of Electronic Engineering, National Yunlin University of Science and Technology, Douliu, Taiwan
Interests: advanced nanomaterials and nanoparticles; MEMS sensing design; hardware/EE/RF circuit and IC design; antenna/microwave wireless design; EMC/EMI design; millimeter-wave and terahertz communication; artificial intelligence
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The development of microwave components and devices has been quite impressive over the past decade. Advances in microwave components and devices have enabled a wide range of applications in communications, radar, navigation, remote sensing, automotive electronics, health care, as well as wireless/microwave power transmission. Additionally, microwave components and devices are becoming increasingly significant for 5G/6G networks, which require high-speed data transmission and low latency. As the demand for more powerful, efficient, and reliable microwave systems continues to grow, so too does the need for further development of microwave components and devices.  

This Special Issue focuses on recent advances in microwave integrated circuits, microwave transmitters/receivers, transceiver, amplifiers, passive components, antennas, and rectifying circuits in the domain of radar systems, 5G/6G communication systems, microwave and terahertz engineering, wireless/microwave power transmission, Internet of Things (IoT), energy harvesting, along with simultaneously wireless information and power transfer. The topics include, but are not limited to, the following:

  • RF/THz integrated microsystems;
  • Microwave /THz antenna design;
  • RF/microwave integrated circuits;
  • Microwave antenna measurements;
  • RF Semiconductor devices in CMOS technology;
  • Microwave and millimeter-wave integrated passive components/circuits;
  • Wide bandgap semiconductor devices and their integrated circuit;
  • Microwave radar sensors;
  • Metamaterials/Metasurfaces.

Dr. Jingchen Wang
Dr. Wencheng Lai
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Micromachines is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • 5G/6G communication systems
  • microwave/wireless power transmission
  • energy harvesting
  • simultaneously wireless information and power transfer
  • Internet of Things (IoT)

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Related Special Issue

Published Papers (12 papers)

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Editorial

Jump to: Research

4 pages, 155 KiB  
Editorial
Editorial for the Special Issue on Recent Advances in Microwave Components and Devices
by Jingchen Wang and Wencheng Lai
Micromachines 2024, 15(2), 180; https://doi.org/10.3390/mi15020180 - 25 Jan 2024
Cited by 8 | Viewed by 1376
Abstract
Microwave components and devices are essential elements of many key communication, sensing, and monitoring systems [...] Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)

Research

Jump to: Editorial

13 pages, 6695 KiB  
Article
A 40–50 GHz RF Front-End with Integrated Local Oscillator Leakage Calibration
by Peigen Zhou, Pinpin Yan, Jixin Chen, Zhe Chen and Wei Hong
Micromachines 2023, 14(11), 2105; https://doi.org/10.3390/mi14112105 - 16 Nov 2023
Viewed by 1675
Abstract
This article presents a transmitter (TX) front-end operating at frequencies covering 40–50 GHz, including a differential quadrature mixer with integrated amplitude and phase imbalance tuning, a power amplifier, and a detection mixer (DM) that supports local oscillator (LO) leakage signal or image signal [...] Read more.
This article presents a transmitter (TX) front-end operating at frequencies covering 40–50 GHz, including a differential quadrature mixer with integrated amplitude and phase imbalance tuning, a power amplifier, and a detection mixer (DM) that supports local oscillator (LO) leakage signal or image signal calibration. Benefiting from the amplitude and phase imbalance tuning network of the in-phase quadrature (IQ) signal generator at the LO input, the TX exhibits more than 30 dBc image signal rejection over the full frequency band without any post-calibration. Based on the LO leakage signal fed back by the DM integrated at the RF output, the LO leakage of the TX has been improved by more than 10 dB through the LO leakage calibration module integrated in the quadrature mixer. When the intermediate frequency (IF) signal is fixed at 1 GHz, the TX’s 1 dB compressed output power (OP1 dB) is higher than 13.5 dBm over the operating band. Thanks to the LO leakage signal calibration unit and the IQ signal generator, the TX is compliant with the error vector magnitude (EVM) requirement of the IEEE 802.11aj standard up to the 64-quadrature amplitude modulation (QAM) operating mode. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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11 pages, 6830 KiB  
Article
A One-Bit Programmable Multi-Functional Metasurface for Microwave Beam Shaping
by Wu Zhang, Jiahan Lin, Zitao Zheng, Yusong Gao, Jifang Tao, Wenli Shang and Meng Zhang
Micromachines 2023, 14(11), 2011; https://doi.org/10.3390/mi14112011 - 29 Oct 2023
Viewed by 1366
Abstract
In this paper, we demonstrate a multi-functional metasurface for microwave beam-shaping application. The metasurface consists of an array of programmable unit cells, and each unit cell is integrated with one varactor diode. By turning the electrical bias on the diode on and off, [...] Read more.
In this paper, we demonstrate a multi-functional metasurface for microwave beam-shaping application. The metasurface consists of an array of programmable unit cells, and each unit cell is integrated with one varactor diode. By turning the electrical bias on the diode on and off, the phase delay of the microwave reflected by the metasurface can be switched between 0 and π at a 6.2 GHz frequency, which makes the metasurface 1-bit-coded. By programming the 1-bit-coded metasurface, the generation of a single-focus beam, a double-focus beam and a focused vortex beam was experimentally demonstrated. Furthermore, the single-focus beam with tunable focal lengths of 54 mm, 103 mm and 152 mm was experimentally observed at 5.7 GHz. The proposed programmable metasurface manifests robust and flexible beam-shaping ability which allows its application to microwave imaging, information transmission and sensing applications. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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15 pages, 13923 KiB  
Article
A Novel Synthesis of Quasi-Chebyshev Ultra-Wideband Bandpass Filter Using Nth Order Stub Loaded Coupled-Line Resonator
by Muhammad Abdul Rehman, Sohail Khalid, Bilal Mushtaq, Mueen Uddin, Jawaid Iqbal, Maha Abdelhaq and Raed Alsaqour
Micromachines 2023, 14(10), 1874; https://doi.org/10.3390/mi14101874 - 29 Sep 2023
Cited by 3 | Viewed by 1297
Abstract
This paper presents a novel synthesis of a quasi-Chebyshev Nth order stub-loaded coupled-line ultra-wideband bandpass filter. A unit element of a proposed filter topology consists of two short-circuited stubs loaded at the edges of coupled lines. A distributed equivalent circuit model of [...] Read more.
This paper presents a novel synthesis of a quasi-Chebyshev Nth order stub-loaded coupled-line ultra-wideband bandpass filter. A unit element of a proposed filter topology consists of two short-circuited stubs loaded at the edges of coupled lines. A distributed equivalent circuit model of a proposed topology is extracted and used to acquire a generalized filtering function. The extracted filtering function is of rational form. The denominator of the filtering function causes a mismatch with Chebyshev type-I polynomials. For conventional narrowband filters, the denominator term can be neglected because of the close vicinity of band-edge frequencies; however, for the ultra-wideband filter response, the factor in the denominator cannot be neglected and hence requires a new mathematical procedure to compensate for the effect of the frequency-dependent term in the denominator. The electrical parameters are calculated using the proposed synthesis and used to design an ideal filter topology on ADS. To validate the proposed design procedure, fabrication is performed on a high-frequency substrate. The proposed filter is miniaturized in size and has good out-of-band performance. The simulated and measured results provide good agreement. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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12 pages, 1763 KiB  
Article
A Mesh Space Mapping Modeling Method with Mesh Deformation for Microwave Components
by Shuxia Yan, Chenglin Li, Mutian Li, Zhimou Li, Xu Wang, Jian Wang and Yaocong Xie
Micromachines 2023, 14(9), 1783; https://doi.org/10.3390/mi14091783 - 17 Sep 2023
Viewed by 1148
Abstract
In this study, a low-cost space mapping (SM) modeling method with mesh deformation is proposed for microwave components. In this approach, the coarse-mesh model with mesh deformation is developed as the coarse model, and the fine-mesh model is simulated as the fine model. [...] Read more.
In this study, a low-cost space mapping (SM) modeling method with mesh deformation is proposed for microwave components. In this approach, the coarse-mesh model with mesh deformation is developed as the coarse model, and the fine-mesh model is simulated as the fine model. The SM technique establishes the mapping relationship between the coarse-mesh model and the fine-mesh model. This approach enables us to combine the computational efficiency of the coarse model with the accuracy of the fine model. The automatic mesh deformation technology is embedded in the coarse model to avoid the discontinuous change in the electromagnetic response. The proposed model consisting of the coarse model and two mapping modules can represent the features of the fine model more accurately, and predict the electromagnetic response of microwave components quickly. The proposed mesh SM modeling technique is applied to the four-pole waveguide filter. The value for the training and test errors in the proposed model is less than 1%, which is lower than that for the ANN models and the existing SM models trained with the same data. Compared with HFSS software, the proposed model can save about 70% CPU time in predicting a set of 100 data. The results show that the proposed method achieves a good modeling accuracy and efficiency with few training data and a low computational cost. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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12 pages, 6119 KiB  
Article
Compact Bandwidth-Enhanced 180-Degree Phase Shifter Using Edge-Coupled Multi-Microstrip and Artificial Transmission Line
by Ding He, Jingxin Fan, Zhiqiang Zhu, Yang Yuan and Zhongjun Yu
Micromachines 2023, 14(9), 1692; https://doi.org/10.3390/mi14091692 - 29 Aug 2023
Cited by 1 | Viewed by 1748
Abstract
Compactness has obtained sufficient importance in wideband phase shifter design considerations, as it is directly related to fabrication cost. In this paper, a novel structure was presented to create compact broadband 180-degree phase shifter, which has the advantages of enhanced bandwidth and significantly [...] Read more.
Compactness has obtained sufficient importance in wideband phase shifter design considerations, as it is directly related to fabrication cost. In this paper, a novel structure was presented to create compact broadband 180-degree phase shifter, which has the advantages of enhanced bandwidth and significantly reduced chip area. The proposed configuration consists of edge-coupled multi-microstrip lines (ECMML) and an artificial transmission line (ATL) with dual-shorted inductors, both of which have the periodic shunt load of capacitors. The ECMML can provide a high coupling coefficient, leading to an increase in the bandwidth, while the introduced capacitors can greatly reduce the line length (35.8% of the conventional method). To verify the relevant mechanisms, a wideband switched network with compact dimensions of 0.67 × 0.46 mm2 was designed via 0.15-micrometer GaAs pHEMT technology. Combined with the measured switch transistor, it was shown that the proposed phase shifter exhibits an insertion loss of less than 2 dB, a return loss of greater than 12 dB, a maximum phase error of less than 0.6° and a channel amplitude difference of less than 0.1 dB in the range of 10 to 20 GHz. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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10 pages, 4556 KiB  
Article
Ultra-Compact Low-Pass Spoof Surface Plasmon Polariton Filter Based on Interdigital Structure
by Zhou-Hao Gao, Xin-Shuo Li, Man Mao, Chen Sun, Feng-Xue Liu, Le Zhang and Lei Zhao
Micromachines 2023, 14(9), 1687; https://doi.org/10.3390/mi14091687 - 29 Aug 2023
Cited by 2 | Viewed by 1337
Abstract
An ultra-compact low-pass spoof surface plasmon polariton (SSPP) filter based on an interdigital structure (IS) is designed. Simulated dispersion curves show that adding the interdigital structure in an SSPP unit effectively reduces its asymptotic frequency compared with traditional and T-shaped SSPP geometries, and [...] Read more.
An ultra-compact low-pass spoof surface plasmon polariton (SSPP) filter based on an interdigital structure (IS) is designed. Simulated dispersion curves show that adding the interdigital structure in an SSPP unit effectively reduces its asymptotic frequency compared with traditional and T-shaped SSPP geometries, and the unit dimensions can be conversely reduced. Based on that, three IS-based SSPP units are, respectively, designed with different maximum intrinsic frequencies and similar asymptotic frequencies to constitute the matching and waveguide sections of the proposed filter, and the unit number in the waveguide section is adjusted to improve the out-of-band suppression. Simulation results illustrate the efficient transmission in the 0~5.66 GHz passband, excellent out-of-band suppression (over 24 dB) in the 5.95~12 GHz stopband and ultra-shape roll-off at 5.74 GHz of the proposed filter. Measurement results on a fabricated prototype validate the design, with a measured cut-off frequency of 5.53 GHz and an ultra-compact geometry of 0.5 × 0.16 λ02. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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10 pages, 5630 KiB  
Article
An 8–18 GHz 90° Switched T-Type Phase Shifter
by Jialong Zeng, Yuxin Ren, Cheng Tan, Yang Yuan, Jiaxuan Li and Zhongjun Yu
Micromachines 2023, 14(8), 1569; https://doi.org/10.3390/mi14081569 - 7 Aug 2023
Viewed by 1469
Abstract
This paper proposes a novel 8–18 GHz 90° switched T-type phase shifter (TPS). In contrast to the conventional TPS, the proposed TPS adds a compensation capacitance to greatly enhance the phase shifting capacity. Moreover, the designed structure also integrates a filtering compensation network, [...] Read more.
This paper proposes a novel 8–18 GHz 90° switched T-type phase shifter (TPS). In contrast to the conventional TPS, the proposed TPS adds a compensation capacitance to greatly enhance the phase shifting capacity. Moreover, the designed structure also integrates a filtering compensation network, which can effectively achieve a flat relative phase shift in a wide band. The proposed 90° TPS is fabricated using 0.15 μm GaAs pHEMT technology. The TPS achieves homogeneous phase shift at 8–18 GHz, with the measured phase error of less than ±1.5°. The insertion loss of the proposed phase shifter is 1.3–2.6 dB, and the chip size is merely 0.53 × 0.86 mm2. Thanks to these excellent performance characteristics, the designed phase shifter is well-suited for ultra-wideband wireless communication and radar systems. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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16 pages, 3997 KiB  
Article
Microwave Sensor for the Determination of DMSO Concentration in Water–DMSO Binary Mixture
by Supakorn Harnsoongnoen and Benjaporn Buranrat
Micromachines 2023, 14(7), 1378; https://doi.org/10.3390/mi14071378 - 5 Jul 2023
Viewed by 1832
Abstract
This research aims to develop a microwave sensor to accurately measure the concentration of dimethyl sulfoxide (DMSO) in water–DMSO binary mixtures. The proposed sensor will utilize microwave frequency measurements to determine the DMSO concentration, providing a non-invasive and efficient method for analyzing DMSO [...] Read more.
This research aims to develop a microwave sensor to accurately measure the concentration of dimethyl sulfoxide (DMSO) in water–DMSO binary mixtures. The proposed sensor will utilize microwave frequency measurements to determine the DMSO concentration, providing a non-invasive and efficient method for analyzing DMSO solutions. The research will involve the design, fabrication, and testing of the sensor, as well as the development of an appropriate calibration model. The outcomes of this study will contribute to improved monitoring and quality control in various fields, including pharmaceuticals, chemical synthesis, and biomedical research. The binary mixtures of dimethyl sulfoxide (DMSO) and water with varying concentrations were investigated in the frequency range of 1 GHz to 5 GHz at room temperature using a microwave sensor. The proposed microwave sensor design was based on an interdigital capacitor (IDC) microstrip antenna loaded with a hexagonal complementary ring resonator (HCRR). The performance of the sensor, fabricated using the print circuit board (PCB) technique, was validated through simulations and experiments. The reflection coefficient (S11) and resonance frequency (Fr) of binary mixtures of DMSO and water solutions were recorded and analyzed for DMSO concentrations ranging from 0% v/v to 75% v/v. Mathematical models were developed to analyze the data, and laboratory tests showed that the sensor can detect levels of DMSO/water binary mixtures. The sensor is capable of detecting DMSO concentrations ranging from 0% v/v to 75% v/v, with a maximum sensitivity of 0.138 dB/% for S11 and ΔS11 and 0.2 MHz/% for Fr and ΔFr at a concentration of 50% v/v. The developed microwave sensor can serve as an alternative for detecting DMSO concentrations in water using a simple and cost-effective technique. This method can effectively analyze a wide range of concentrations, including highly concentrated solutions, quickly and easily. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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10 pages, 2281 KiB  
Article
A Ku-Band Broadband Stacked FET Power Amplifier Using 0.15 μm GaAs pHEMT
by Jiaxuan Li, Yang Yuan, Bin Yuan, Jingxin Fan, Jialong Zeng and Zhongjun Yu
Micromachines 2023, 14(6), 1276; https://doi.org/10.3390/mi14061276 - 20 Jun 2023
Cited by 1 | Viewed by 1861
Abstract
To meet the application requirements of broadband radar systems for broadband power amplifiers, a Ku-band broadband power amplifier (PA) microwave monolithic integrated circuit (MMIC) based on a 0.15 µm gallium arsenide (GaAs) high-electron-mobility transistor (HEMT) technology is proposed in this paper. In this [...] Read more.
To meet the application requirements of broadband radar systems for broadband power amplifiers, a Ku-band broadband power amplifier (PA) microwave monolithic integrated circuit (MMIC) based on a 0.15 µm gallium arsenide (GaAs) high-electron-mobility transistor (HEMT) technology is proposed in this paper. In this design, the advantages of the stacked FET structure in the broadband PA design are illustrated by theoretical derivation. The proposed PA uses a two-stage amplifier structure and a two-way power synthesis structure to achieve high-power gain and high-power design, respectively. The fabricated power amplifier was tested under continuous wave conditions, and the test results showed a peak power of 30.8 dBm at 16 GHz. At 15 to 17.5 GHz, the output power was above 30 dBm with a PAE of more than 32%. The fractional bandwidth of the 3 dB output power was 30%. The chip area was 3.3 × 1.2 mm2 and included input and output test pads. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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15 pages, 7346 KiB  
Article
An Inductor-Loaded Single-Port Planar Dual-Broadband Antenna with Stable Gains
by Wenxing An, Xinyu Xu, Jian Wang and Shenrong Li
Micromachines 2023, 14(6), 1233; https://doi.org/10.3390/mi14061233 - 11 Jun 2023
Cited by 1 | Viewed by 1681
Abstract
A single-port dual-wideband base-station antenna is reported here for mobile communication systems. Loop and stair-shaped structures with lumped inductors are adopted for dual-wideband operation. The low and high bands share the same radiation structure to accomplish a compact design. The operation principle of [...] Read more.
A single-port dual-wideband base-station antenna is reported here for mobile communication systems. Loop and stair-shaped structures with lumped inductors are adopted for dual-wideband operation. The low and high bands share the same radiation structure to accomplish a compact design. The operation principle of the proposed antenna is analyzed, and the effects of the lumped inductors are studied. The measured operation bands are from 0.64 GHz to 1 GHz and from 1.59 GHz to 2.82 GHz, with relative bandwidths of 43.9% and 55.8%, respectively. Broadside radiation patterns and stable gain with a variation of less than 2.2 dB are achieved for both bands. The inductor-loading technology is proven to be an effective way for dual-band antenna design with wide bandwidth and stable gain performance. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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14 pages, 6010 KiB  
Article
Textile Bandwidth-Enhanced Polarization-Reconfigurable Half-Mode Substrate-Integrated Cavity Antenna
by Feng-Xue Liu, Jie Cui, Fan-Yu Meng, Tian-Yu Jiang, Shao-Fei Yan, Shuai Chao and Lei Zhao
Micromachines 2023, 14(5), 934; https://doi.org/10.3390/mi14050934 - 25 Apr 2023
Cited by 3 | Viewed by 1637
Abstract
A textile bandwidth-enhanced polarization-reconfigurable half-mode substrate-integrated cavity antenna was designed for wearable applications. A slot was cut out from the patch of a basic textile HMSIC antenna to excite two close resonances to form a wide −10 dB impedance band. The simulated axial [...] Read more.
A textile bandwidth-enhanced polarization-reconfigurable half-mode substrate-integrated cavity antenna was designed for wearable applications. A slot was cut out from the patch of a basic textile HMSIC antenna to excite two close resonances to form a wide −10 dB impedance band. The simulated axial ratio curve indicates the linear and circular polarization of the antenna radiation at different frequencies. Based on that, two sets of snap buttons were added at the radiation aperture to shift the −10 dB band. Therefore, a larger frequency range can be flexibly covered, and the polarization can be reconfigured at a fixed frequency by switching the state of snap buttons. According to the measured results on a fabricated prototype, the −10 dB impedance band of the proposed antenna can be reconfigured to cover 2.29~2.63 GHz (13.9% fractional bandwidth), and the circular/linear polarization radiation can be observed at 2.42 GHz with buttons OFF/ON. Additionally, simulations and measurements were carried out to validate the design and to study the effects of human body and bending conditions on the antenna performance. Full article
(This article belongs to the Special Issue Recent Advances in Microwave Components and Devices)
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