Pub Date : 2024-02-16DOI: 10.1017/s1759078724000230
Ramesh Amugothu, Vakula Damera
In the proposed paper, a novel design and realization of a wide-band, oblique angle-insensitive metamaterial absorbers are presented. The absorber is designed to work over a wide range of frequencies, making it suitable for Ku-band applications. To get wide band absorption, a novel SM-shaped design with a square-tooth circular ring resonator structure is designed efficiently. The unit cell structure is designed with a dielectric substrate (FR4) with a thickness of 3.2 mm (0.16λ0), where λ0 is the wavelength of free space. The novel design of this configuration leads to wideband absorption with respect to a conventional absorber. Several physical parameters are also investigated, such as the dielectric constant, permittivity, permeability, impedance, and negative refractive index. The simulation and experimental results show from 13.60 to 16.14 GHz with 99.1% absorption, which is excellent agreement. The analysis of the proposed design indicates that it possesses the remarkable feature of being insensitive to polarization while also exhibiting high absorption even when the angle of incidence varies. For both the simulation and experiment, results are consistent with a frequency range of 13.60–16.14 GHz for normal incidence. Almost perfect absorption works well for solar cells, EM detection, and imaging applications.
本文提出了一种新颖的宽带斜角不敏感超材料吸收器的设计和实现方法。该吸收器的设计工作频率范围很宽,因此适用于 Ku 波段应用。为了获得宽带吸收,我们有效地设计了一种具有方齿圆环谐振器结构的新型 SM 形设计。单元单元结构设计采用厚度为 3.2 毫米(0.16λ0)的介质基板(FR4),其中 λ0 为自由空间的波长。与传统吸收器相比,这种结构的新颖设计实现了宽带吸收。此外,还研究了几个物理参数,如介电常数、介电常数、磁导率、阻抗和负折射率。模拟和实验结果表明,在 13.60 至 16.14 GHz 范围内,吸收率达到 99.1%,两者非常吻合。对拟议设计的分析表明,它具有对极化不敏感的显著特点,同时即使入射角度变化,也能表现出高吸收率。模拟和实验结果一致,正常入射的频率范围为 13.60-16.14 GHz。近乎完美的吸收特性非常适合太阳能电池、电磁探测和成像应用。
{"title":"A wideband, thin, dual-negative, and polarization-independent square-tooth circular ring resonator-based metamaterial absorber for Ku-band applications","authors":"Ramesh Amugothu, Vakula Damera","doi":"10.1017/s1759078724000230","DOIUrl":"https://doi.org/10.1017/s1759078724000230","url":null,"abstract":"In the proposed paper, a novel design and realization of a wide-band, oblique angle-insensitive metamaterial absorbers are presented. The absorber is designed to work over a wide range of frequencies, making it suitable for Ku-band applications. To get wide band absorption, a novel SM-shaped design with a square-tooth circular ring resonator structure is designed efficiently. The unit cell structure is designed with a dielectric substrate (FR4) with a thickness of 3.2 mm (0.16<jats:italic>λ</jats:italic><jats:sub>0</jats:sub>), where <jats:italic>λ</jats:italic><jats:sub>0</jats:sub> is the wavelength of free space. The novel design of this configuration leads to wideband absorption with respect to a conventional absorber. Several physical parameters are also investigated, such as the dielectric constant, permittivity, permeability, impedance, and negative refractive index. The simulation and experimental results show from 13.60 to 16.14 GHz with 99.1% absorption, which is excellent agreement. The analysis of the proposed design indicates that it possesses the remarkable feature of being insensitive to polarization while also exhibiting high absorption even when the angle of incidence varies. For both the simulation and experiment, results are consistent with a frequency range of 13.60–16.14 GHz for normal incidence. Almost perfect absorption works well for solar cells, EM detection, and imaging applications.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, a novel tunable dual-band bandpass filter (BPF) with independently controlled passbands and constant absolute bandwidth (CABW) is proposed. The CABW passbands of designed dual-band BPF are obtained using manageable electric and magnetic mix coupling. Furthermore, the multiple transmission paths from the input port to the output port are extended for extra transmission zeros, which results in modified selectivity of the proposed dual-band BPF. The tunability and switchability of the developed filter can be implemented by introducing a single bias voltage of varactors for each band. For the tunable dual-band BPF, the simulated results show that the center frequency (CF) of the first passband varies from 2.38 to 2.68 GHz, and the CF of the second passband varies from 3.28 to 3.88 GHz, while 3-dB absolute bandwidths are 101 ± 7 MHz and 98 ± 4 MHz, respectively. Moreover, the two passbands of the filter can also be independently switched by removing the voltage imposed on the varactor CV1 and CV2. The measured results agree well with simulated results, which verify the design theory.
{"title":"Design of dual-band tunable bandpass filter with constant absolute bandwidth based on triple transmission path","authors":"Jing Guo, Lirong Qian, Litian Wang, Cuiping Li, Yahui Tian, Honglang Li","doi":"10.1017/s1759078724000138","DOIUrl":"https://doi.org/10.1017/s1759078724000138","url":null,"abstract":"In this paper, a novel tunable dual-band bandpass filter (BPF) with independently controlled passbands and constant absolute bandwidth (CABW) is proposed. The CABW passbands of designed dual-band BPF are obtained using manageable electric and magnetic mix coupling. Furthermore, the multiple transmission paths from the input port to the output port are extended for extra transmission zeros, which results in modified selectivity of the proposed dual-band BPF. The tunability and switchability of the developed filter can be implemented by introducing a single bias voltage of varactors for each band. For the tunable dual-band BPF, the simulated results show that the center frequency (CF) of the first passband varies from 2.38 to 2.68 GHz, and the CF of the second passband varies from 3.28 to 3.88 GHz, while 3-dB absolute bandwidths are 101 ± 7 MHz and 98 ± 4 MHz, respectively. Moreover, the two passbands of the filter can also be independently switched by removing the voltage imposed on the varactor C<jats:sub>V1</jats:sub> and C<jats:sub>V2</jats:sub>. The measured results agree well with simulated results, which verify the design theory.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-13DOI: 10.1017/s1759078724000059
Guohua Liu, Jianyuan Yu, Yijun Lin
This paper proposes a design method for designing a wideband filtering power amplifier (PA) based on terminated coupled line structure (TCLS). This method generates four transmission zeros and three transmission poles by loading stepped impedance resonator and short-circuit stubs on the four ports of TCLS, which greatly optimizes the in-band return loss and stopband suppression of the output matching network. In addition, the effective suppression of the second harmonic also increases the efficiency of the PA. In order to verify the effectiveness and superiority of this design method, a wideband bandpass filtering PA is designed and manufactured in 2.9–3.7 GHz. Measurement results show that the saturated output power is from 40.1 dBm to 41.2 dBm, the drain efficiency is greater than 60.3%, and the gain is 10–11.2 dB.
{"title":"Wideband filtering power amplifier based on terminated coupled line structure","authors":"Guohua Liu, Jianyuan Yu, Yijun Lin","doi":"10.1017/s1759078724000059","DOIUrl":"https://doi.org/10.1017/s1759078724000059","url":null,"abstract":"This paper proposes a design method for designing a wideband filtering power amplifier (PA) based on terminated coupled line structure (TCLS). This method generates four transmission zeros and three transmission poles by loading stepped impedance resonator and short-circuit stubs on the four ports of TCLS, which greatly optimizes the in-band return loss and stopband suppression of the output matching network. In addition, the effective suppression of the second harmonic also increases the efficiency of the PA. In order to verify the effectiveness and superiority of this design method, a wideband bandpass filtering PA is designed and manufactured in 2.9–3.7 GHz. Measurement results show that the saturated output power is from 40.1 dBm to 41.2 dBm, the drain efficiency is greater than 60.3%, and the gain is 10–11.2 dB.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-12DOI: 10.1017/s1759078724000229
Chao Huang, Chenjiang Guo, Xia Ma, Yi Yuan, Jun Ding
An enhanced wideband tracking method for characteristic modes (CMs) is investigated in this paper. The method consists of three stages, and its core tracking stage (CTS) is based on a classical eigenvector correlation-based algorithm. To decrease the tracking time and eliminate the crossing avoidance (CRA), we append a commonly used eigenvalue filter (EF) as the preprocessing stage and a novel postprocessing stage to the CTS. The proposed postprocessing stage can identify all CRA mode pairs by analyzing their trajectory and correlation characteristics. Subsequently, it can predict corresponding CRA frequencies and correct problematic qualities rapidly. Considering potential variations in eigenvector numbers at consecutive frequency samples caused by the EF, a new execution condition for the adaptive frequency adjustment in the CTS is introduced. Finally, CMs of a conductor plate and a fractal structure are investigated to demonstrate the performance of the proposed method, and the obtained results are discussed.
{"title":"An enhanced wideband tracking method for characteristic modes","authors":"Chao Huang, Chenjiang Guo, Xia Ma, Yi Yuan, Jun Ding","doi":"10.1017/s1759078724000229","DOIUrl":"https://doi.org/10.1017/s1759078724000229","url":null,"abstract":"An enhanced wideband tracking method for characteristic modes (CMs) is investigated in this paper. The method consists of three stages, and its core tracking stage (CTS) is based on a classical eigenvector correlation-based algorithm. To decrease the tracking time and eliminate the crossing avoidance (CRA), we append a commonly used eigenvalue filter (EF) as the preprocessing stage and a novel postprocessing stage to the CTS. The proposed postprocessing stage can identify all CRA mode pairs by analyzing their trajectory and correlation characteristics. Subsequently, it can predict corresponding CRA frequencies and correct problematic qualities rapidly. Considering potential variations in eigenvector numbers at consecutive frequency samples caused by the EF, a new execution condition for the adaptive frequency adjustment in the CTS is introduced. Finally, CMs of a conductor plate and a fractal structure are investigated to demonstrate the performance of the proposed method, and the obtained results are discussed.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-09DOI: 10.1017/s1759078723001034
Guorui Han, Zijun Zheng, Jinrong Su, Hao Yuan, Wenmei Zhang
A novel wideband nonuniform metasurface antenna with stable gain is demonstrated. The nonuniform metasurface is composed of square patches and rings and is excited by a slot antenna. Based on characteristic mode analysis, two characteristic modes with same current direction are selected to achieve stable radiation performance in a wide frequency range. The wideband operation is achieved by assembling the resonant modes of the metasurface and slot antenna. The measured results show that the −10 dB impedance bandwidth of the proposed antenna is from 4.3 to 8.4 GHz (64.57%), and the 2 dB gain bandwidth is from 4.3 to 6.2 GHz (36.2%) with a peak gain value of 9.42 dBi. Moreover, broadside radiation performance is achieved.
演示了一种具有稳定增益的新型宽带非均匀元面天线。非均匀元面由方形贴片和环组成,并由槽形天线激励。根据特征模态分析,选择了两个电流方向相同的特征模态,从而在较宽的频率范围内实现了稳定的辐射性能。通过组合元表面和槽形天线的谐振模式,实现了宽带工作。测量结果表明,拟议天线的 -10 dB 阻抗带宽为 4.3 至 8.4 GHz(64.57%),2 dB 增益带宽为 4.3 至 6.2 GHz(36.2%),峰值增益为 9.42 dBi。此外,还实现了宽边辐射性能。
{"title":"Wideband nonuniform metasurface antenna with stable gain","authors":"Guorui Han, Zijun Zheng, Jinrong Su, Hao Yuan, Wenmei Zhang","doi":"10.1017/s1759078723001034","DOIUrl":"https://doi.org/10.1017/s1759078723001034","url":null,"abstract":"A novel wideband nonuniform metasurface antenna with stable gain is demonstrated. The nonuniform metasurface is composed of square patches and rings and is excited by a slot antenna. Based on characteristic mode analysis, two characteristic modes with same current direction are selected to achieve stable radiation performance in a wide frequency range. The wideband operation is achieved by assembling the resonant modes of the metasurface and slot antenna. The measured results show that the −10 dB impedance bandwidth of the proposed antenna is from 4.3 to 8.4 GHz (64.57%), and the 2 dB gain bandwidth is from 4.3 to 6.2 GHz (36.2%) with a peak gain value of 9.42 dBi. Moreover, broadside radiation performance is achieved.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-08DOI: 10.1017/s1759078723001617
Satish Kumar, Gopi Ram, Durbadal Mandal, Rajib Kar
Circular antenna array (CAA) is one of the most widely used antenna array designs. This paper addresses the design challenges of the CAA with the non-uniform single ring, which is placed in an X-Y plane with the best sidelobe level (SLL) and improved first null beamwidth (FNBW). It has been solved using differential evolution, craziness-based particle swarm optimization (CRPSO), and novel particle swarm optimization (NPSO) techniques. An optimal combination of feeding current and inter-element spacing provides an array pattern with the best SLL and improved FNBW, as well as some other parameter calculations of the antenna array like maximum directivity, maximum effective aperture, total effective aperture, maximum beam area, total beam area, circumference, and radius of the CAAs using these techniques. There are six designs of CAAs with different antenna elements (i.e., 10-, 12-, 16-, 20-, 36-, and 64-elements) which have been taken into account. Simulations are done in MATLAB. Based on various simulation results, we can analyze the performance of SLL and FNBW with other parameters using NPSO and compare them with different techniques of CAAs, as shown in the numerical analysis and simulation result section.
{"title":"Optimal pattern synthesis of circular antenna arrays with improved effective aperture and beam area","authors":"Satish Kumar, Gopi Ram, Durbadal Mandal, Rajib Kar","doi":"10.1017/s1759078723001617","DOIUrl":"https://doi.org/10.1017/s1759078723001617","url":null,"abstract":"Circular antenna array (CAA) is one of the most widely used antenna array designs. This paper addresses the design challenges of the CAA with the non-uniform single ring, which is placed in an X-Y plane with the best sidelobe level (SLL) and improved first null beamwidth (FNBW). It has been solved using differential evolution, craziness-based particle swarm optimization (CRPSO), and novel particle swarm optimization (NPSO) techniques. An optimal combination of feeding current and inter-element spacing provides an array pattern with the best SLL and improved FNBW, as well as some other parameter calculations of the antenna array like maximum directivity, maximum effective aperture, total effective aperture, maximum beam area, total beam area, circumference, and radius of the CAAs using these techniques. There are six designs of CAAs with different antenna elements (i.e., 10-, 12-, 16-, 20-, 36-, and 64-elements) which have been taken into account. Simulations are done in MATLAB. Based on various simulation results, we can analyze the performance of SLL and FNBW with other parameters using NPSO and compare them with different techniques of CAAs, as shown in the numerical analysis and simulation result section.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-08DOI: 10.1017/s1759078724000199
Yue Xie, Jianping Zhao, Yurong Sun, Juan Xu
This paper presents a broadband circularly polarized (CP) antenna array for millimeter-wave applications, and the antenna array has the advantages of wide impedance bandwidth (IBW), novel CP design, and low profile. The antenna unit consists of a two-layer substrate and two pairs of magnetoelectric dipoles. Stepped microstrip lines coupled by rectangular slits form a feeder network for easy integration. The axial ratio bandwidth (ARBW) is extended because a pair of parasitic patches is loaded and an elliptical perturbation is added. The simulation results show that the antenna has an ARBW of 18.6% (26.4–31.9 GHz) and an IBW of 45.5% (20.6–32.7 GHz), with a gain greater than 7.11 dBic in the IBW. To improve the gain of the antenna, a 2 × 2 antenna array is designed, fabricated, and measured. The measured results show that the array has an ARBW of 16.6% (26.42–31.21 GHz), an IBW of 41.6% (22.28–33.97 GHz), a peak gain of 13.89 dBic in the IBW, the cross-polarization levels in the xoz-plane and yoz-plane are above 20 dB, and a radiation efficiency greater than 89%.
{"title":"A broadband circularly polarized antenna for millimeter-wave applications","authors":"Yue Xie, Jianping Zhao, Yurong Sun, Juan Xu","doi":"10.1017/s1759078724000199","DOIUrl":"https://doi.org/10.1017/s1759078724000199","url":null,"abstract":"This paper presents a broadband circularly polarized (CP) antenna array for millimeter-wave applications, and the antenna array has the advantages of wide impedance bandwidth (IBW), novel CP design, and low profile. The antenna unit consists of a two-layer substrate and two pairs of magnetoelectric dipoles. Stepped microstrip lines coupled by rectangular slits form a feeder network for easy integration. The axial ratio bandwidth (ARBW) is extended because a pair of parasitic patches is loaded and an elliptical perturbation is added. The simulation results show that the antenna has an ARBW of 18.6% (26.4–31.9 GHz) and an IBW of 45.5% (20.6–32.7 GHz), with a gain greater than 7.11 dBic in the IBW. To improve the gain of the antenna, a 2 × 2 antenna array is designed, fabricated, and measured. The measured results show that the array has an ARBW of 16.6% (26.42–31.21 GHz), an IBW of 41.6% (22.28–33.97 GHz), a peak gain of 13.89 dBic in the IBW, the cross-polarization levels in the xoz-plane and yoz-plane are above 20 dB, and a radiation efficiency greater than 89%.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-08DOI: 10.1017/s1759078724000187
K. H. Murali Naik, Amit K. Singh, D. Rama Krishna
This paper proposes a lightweight frequency selective surface polarization-insensitive wideband metamaterial absorber in C band and X band that employs only a few resistive elements. The proposed absorber is embodied with four quadrature slotted inner circular patch, which is horizontally and vertically bisected, and outer concentric copper rings of 0.035 mm thickness are attached with four lumped resistors placed at 90° apart. A slotted inner circular patch provides significant inductive and capacitive loading. The absorption bandwidth of 8.02 GHz with more than 90% absorption is observed from 5.69 to 13.71 GHz under normal incidence and maintains almost same absorptivity range under oblique incidence up to 45° in both transverse electric mode and transverse magnetic mode. The designed metamaterial absorber is fabricated and measured using free space measurement technique. The actual experiments and the simulated ones are in good agreement.
本文提出了一种轻型频率选择性表面偏振不敏感宽带超材料吸波材料,适用于 C 波段和 X 波段,只采用了几个电阻元件。拟议的吸收器由四个正交开槽内圆贴片组成,内圆贴片在水平和垂直方向上被一分为二,厚度为 0.035 毫米的外同心铜环上连接着四个相距 90° 的块状电阻器。开槽内圆贴片提供了重要的电感和电容负载。在正常入射情况下,吸收带宽为 8.02 GHz,吸收率超过 90%,频率范围从 5.69 GHz 到 13.71 GHz;在斜入射情况下,横向电模式和横向磁模式的吸收率范围几乎相同,最高可达 45°。设计的超材料吸收器是利用自由空间测量技术制造和测量的。实际实验结果与模拟结果非常吻合。
{"title":"Polarization insensitive passive loaded wideband metamaterial absorber","authors":"K. H. Murali Naik, Amit K. Singh, D. Rama Krishna","doi":"10.1017/s1759078724000187","DOIUrl":"https://doi.org/10.1017/s1759078724000187","url":null,"abstract":"This paper proposes a lightweight frequency selective surface polarization-insensitive wideband metamaterial absorber in C band and X band that employs only a few resistive elements. The proposed absorber is embodied with four quadrature slotted inner circular patch, which is horizontally and vertically bisected, and outer concentric copper rings of 0.035 mm thickness are attached with four lumped resistors placed at 90° apart. A slotted inner circular patch provides significant inductive and capacitive loading. The absorption bandwidth of 8.02 GHz with more than 90% absorption is observed from 5.69 to 13.71 GHz under normal incidence and maintains almost same absorptivity range under oblique incidence up to 45° in both transverse electric mode and transverse magnetic mode. The designed metamaterial absorber is fabricated and measured using free space measurement technique. The actual experiments and the simulated ones are in good agreement.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-08DOI: 10.1017/s1759078724000102
Viktor Mattsson, Mauricio D. Perez, Laya Joseph, Robin Augustine
The Muscle Analyzer System (MAS) project wants to create a standalone microwave device that can assess the muscle quality, called the MAS device. To achieve that an algorithm that can derive the properties of skin, fat and muscle from the measurements is needed. This paper presents a machine learning algorithm that aims to do precisely that. The algorithm relies on first predicting the skin using the data from the MAS device, then predicting the fat again using the data from the MAS but also the predicted skin value and lastly the muscle is predicted using the microwave data together with the skin and fat predictions. Data have been collected in phantom experiments, materials that mimick the dielectric properties of human tissues. The algorithm is trained to predict the properties of said phantoms. The results show that the prediction for skin thickness works well, the fat thickness prediction is okay but the muscle prediction struggles. This is partly due to the error from the skin and fat layers are propagated to the muscle layer and partly because the muscle layer is farthest away from the sensor, which makes getting information from that layer harder.
肌肉分析仪系统(MAS)项目希望创建一个能够评估肌肉质量的独立微波设备,称为 MAS 设备。为实现这一目标,需要一种能从测量结果中推导出皮肤、脂肪和肌肉属性的算法。本文介绍的机器学习算法正是为了实现这一目标。该算法首先利用 MAS 设备的数据预测皮肤,然后利用 MAS 的数据以及预测的皮肤值再次预测脂肪,最后利用微波数据以及皮肤和脂肪预测值预测肌肉。数据是在模拟人体组织介电特性的模型实验中收集的。对算法进行了训练,以预测上述模型的特性。结果显示,对皮肤厚度的预测效果良好,对脂肪厚度的预测尚可,但对肌肉的预测却很困难。这一方面是由于皮肤和脂肪层的误差会传播到肌肉层,另一方面是由于肌肉层离传感器最远,因此很难从该层获取信息。
{"title":"Machine learning algorithm to extract properties of ATE phantoms from microwave measurements","authors":"Viktor Mattsson, Mauricio D. Perez, Laya Joseph, Robin Augustine","doi":"10.1017/s1759078724000102","DOIUrl":"https://doi.org/10.1017/s1759078724000102","url":null,"abstract":"The Muscle Analyzer System (MAS) project wants to create a standalone microwave device that can assess the muscle quality, called the MAS device. To achieve that an algorithm that can derive the properties of skin, fat and muscle from the measurements is needed. This paper presents a machine learning algorithm that aims to do precisely that. The algorithm relies on first predicting the skin using the data from the MAS device, then predicting the fat again using the data from the MAS but also the predicted skin value and lastly the muscle is predicted using the microwave data together with the skin and fat predictions. Data have been collected in phantom experiments, materials that mimick the dielectric properties of human tissues. The algorithm is trained to predict the properties of said phantoms. The results show that the prediction for skin thickness works well, the fat thickness prediction is okay but the muscle prediction struggles. This is partly due to the error from the skin and fat layers are propagated to the muscle layer and partly because the muscle layer is farthest away from the sensor, which makes getting information from that layer harder.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139753886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-02DOI: 10.1017/s1759078724000035
Andrea Quirini, Giovanni Paolo Blasone, Fabiola Colone, Pierfrancesco Lombardo
In this paper, we investigate low-cost solutions for enabling ground moving target indication applications with multichannel mobile passive radar systems. As known, in order to be competitive with their active counterparts, passive radars are typically characterized by severe constraints in terms of cost, complexity, and compactness, especially when installed on moving platforms. On the one hand, carrying out the computations onboard requires processing techniques as simple as possible. On the other hand, the need for lightweight and compact systems that can be installed on a moving platform requires using a limited number of receiving channels. To meet these requirements, we propose a series of nonadaptive detectors based on multichannel displaced phase center antennas, which allow suppressing the Doppler-spread clutter component without requiring computationally intensive space–time adaptive processing techniques. Moreover, we explore the use of nonuniformly spaced array configurations on receive, which represent a good alternative to conventional uniform linear arrays when a limited number of receiving channels can be implemented. The effectiveness of the proposed processing techniques and antenna design solutions is demonstrated via numerical analysis for the case of a DVB-T-based mobile passive radar system.
{"title":"Low-cost solutions for mobile passive radar based on multichannel DPCA and NULA configurations","authors":"Andrea Quirini, Giovanni Paolo Blasone, Fabiola Colone, Pierfrancesco Lombardo","doi":"10.1017/s1759078724000035","DOIUrl":"https://doi.org/10.1017/s1759078724000035","url":null,"abstract":"In this paper, we investigate low-cost solutions for enabling ground moving target indication applications with multichannel mobile passive radar systems. As known, in order to be competitive with their active counterparts, passive radars are typically characterized by severe constraints in terms of cost, complexity, and compactness, especially when installed on moving platforms. On the one hand, carrying out the computations onboard requires processing techniques as simple as possible. On the other hand, the need for lightweight and compact systems that can be installed on a moving platform requires using a limited number of receiving channels. To meet these requirements, we propose a series of nonadaptive detectors based on multichannel displaced phase center antennas, which allow suppressing the Doppler-spread clutter component without requiring computationally intensive space–time adaptive processing techniques. Moreover, we explore the use of nonuniformly spaced array configurations on receive, which represent a good alternative to conventional uniform linear arrays when a limited number of receiving channels can be implemented. The effectiveness of the proposed processing techniques and antenna design solutions is demonstrated via numerical analysis for the case of a DVB-T-based mobile passive radar system.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139662344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}