{"title":"Multiband circularly-polarized stacked elliptical patch antenna with eye-shaped slot for GNSS applications","authors":"Ahmad Abdalrazik, Ahmed Gomaa, Asmaa Afifi","doi":"10.1017/s175907872400045x","DOIUrl":"https://doi.org/10.1017/s175907872400045x","url":null,"abstract":"This paper introduces a tri-band stacked elliptical patch antenna featuring a right-handed circular polarized, designed to operate at the L2, L5, and L1 Global Navigation Satellite System bands. Initially, an elliptic patch is constructed and fed by a probe feed to generate <jats:italic>TM</jats:italic><jats:sub>110</jats:sub> and <jats:italic>TM</jats:italic><jats:sub>210</jats:sub> modes at resonance frequencies calculated using Mathieu functions. The probe position is precisely adjusted to excite the quasi-orthogonal mode of <jats:italic>TM</jats:italic><jats:sub>110</jats:sub> to generate circularly polarized (CP) waves at the L2 and L5 bands. Subsequently, an eye-shaped aperture is engraved into the elliptical patch to enhance the axial ratio (AR) beamwidth in the L2 and L5 bands and stimulate the orthogonal mode of <jats:italic>TM</jats:italic><jats:sub>210</jats:sub> to produce CP waves at the L1 band. Lastly, a stacked partially elliptical parasitic element is placed beneath the upper slotted elliptical patch to enhance the orthogonality of <jats:italic>TM</jats:italic><jats:sub>210</jats:sub> surface current versions and thus improve the AR beamwidth at the L1 band. The proposed antenna shows low reflection coefficient values at 1.12–1.33 (L2/L5), and 1.5–1.66 GHz (L1). The AR beamwidths are 133/213<jats:sup>∘</jats:sup>, 167/163<jats:sup>∘</jats:sup>, and 36/103<jats:sup>∘</jats:sup> at two orthogonal cutplanes at L5, L2, and L1 bands, respectively. The antenna also has decent gains of 6–6.9 dBic across the three bands.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576659","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}
{"title":"Absorptive reconfigurable bandstop filter with ultra-wide frequency tuning range using distributed lossy resonators","authors":"Qun Li","doi":"10.1017/s1759078724000412","DOIUrl":"https://doi.org/10.1017/s1759078724000412","url":null,"abstract":"An absorptive reconfigurable bandstop filter (BSF) with compact size and ultra-wide frequency tuning range using distributed lossy resonators is presented. In each reconfigurable bandstop resonator, a varactor and a PIN diode are utilized as the control and absorption devices. When the PIN diodes are in off and on states, the upper and lower frequency tuning ranges of stopbands can be obtained, respectively. Therefore, the ultra-wide total frequency tuning range which is the combination of the upper and lower frequency tuning ranges can be realized. Meanwhile, the stopband frequency and bandwidth tuning can be independently controlled by bias voltages. The resistances in the varactors and PIN diodes can dissipate the electromagnetic power and thus result in absorptive stopband without using extra absorptive circuits. The stopband suppression level and stopband absorption ratio are proportional to the number of distributed lossy resonators. For demonstration, an absorptive reconfigurable BSF prototype using six pairs of distributed lossy resonators is designed and fabricated. The measured total frequency tuning range is 3.03–6.39 GHz (71%) with the suppression level of 20 dB, while the frequency tuning range with the suppression level of 10 dB is 2.04–6.39 GHz (103%).","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576821","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}
{"title":"A 4 × 4 Butler matrix with switching/steering beams based on new tunable phase difference couplers","authors":"Taleb Mohamed Benaouf, Abdelaziz Hamdoun, Mohamed Himdi, Olivier Lafond, Hassan Ammor","doi":"10.1017/s175907872300154x","DOIUrl":"https://doi.org/10.1017/s175907872300154x","url":null,"abstract":"Basically, a 4 × 4 Butler matrix (BM) connected to an antenna array allows to have four beams, each oriented in a specific direction depending on the excitation port. In this paper, an almost continuously steerable beam system based on a conventional 4 × 4 BM with adjustable phase shift is presented and demonstrated. Here, varicap diodes are used instead of an additional phase shifter. Under different bias levels applied to the couplers throughout these varicap diodes, an output variable phase difference was obtained. A prototype of the proposed tunable BM integrated with an antenna array operating at 3.5 GHz was fabricated and tested. The experimental results show a good agreement with those simulated. A reflection and isolation coefficient better than −15 dB over the entire desired frequency band and an amplitude imbalance lower than ±1.5 dB were achieved. The measured radiating beam under different DC biasing can be oriented from ±6° to ±18° when port 1 or 4 is excited and oriented from ±32° to ±43° for ports 2 and 3.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576741","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}
{"title":"A single-layer multimode high gain circularly polarized metasurface antenna using CMA for C-band applications","authors":"Deepak Gangwar, Ankit Sharma","doi":"10.1017/s1759078724000424","DOIUrl":"https://doi.org/10.1017/s1759078724000424","url":null,"abstract":"This article presents an innovative design for a low-profile, high-gain circularly polarized (CP) antenna using a single-layer metasurface (MTS). The proposed design incorporates an MTS layer, comprising a 4 × 4 array of hexagonal-shaped patches, printed on the top layer of the substrate. The bottom layer features a coplanar waveguide-fed slotted ground. Circular polarization and broadside radiation are achieved through the application of characteristic mode analysis (CMA). CMA is employed to simultaneously excite desired modes, aiming for wideband circular polarization and gain enhancement. Experimental results validate the effectiveness of the design, with compact dimensions of 0.67λ<jats:sub>0</jats:sub> × 0.67λ<jats:sub>0</jats:sub> × 0.04λ<jats:sub>0</jats:sub>. The measurements demonstrate an impressive impedance bandwidth of 84.3% within the 3.7–9.1 GHz. Additionally, a 3-dB axial ratio bandwidth of 18.6% is observed between 4.96 and 5.98 GHz and 3.74% between 8.38 and 8.7 GHz. The antenna exhibits excellent radiation pattern characteristics, featuring a maximum gain of 10.08 dBi at 7.1 GHz. The radiation pattern is symmetrical with broadside directionality, making the antenna well-suited for sensing applications.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576820","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}
{"title":"A compact UWB MIMO antenna augmented with isolation improvement structures in situ with ground stubs and slots","authors":"Jeet Banerjee, Abhik Gorai, Rowdra Ghatak","doi":"10.1017/s1759078723001150","DOIUrl":"https://doi.org/10.1017/s1759078723001150","url":null,"abstract":"An orthogonally oriented microstrip-fed bi-element ultra-wideband (UWB) diversity antenna possessing a super-wide bandwidth, high isolation, and band rejection attributes is proposed. The intended diversity antenna uses a 2nd-order Cayley fractal tree-shaped neutralization line among a pair of radiating square monopoles along with additional components like extended ground stubs, hybrid Koch fractal parasitic elements, and an <jats:italic>L</jats:italic>-shaped defected ground structure to attain high isolation of <−20 dB over 3.1–18 GHz. To nullify the intervention from the existent wireless local area network band, a hybrid Koch–Minkowski slot is carved out from the radiators. A minimal inter-element spacing of 8 mm is attained with the suggested layout measuring 28 mm (<jats:italic>L</jats:italic>) × 42 mm (<jats:italic>W</jats:italic>) in extent. The numerical as well as experimental investigations of vital diversity attributes like the envelope correlation coefficient, mean effective gain, total active reflection coefficient, and multiplexing efficiency depict high diversity actualization. The consistency amidst the simulation as well as the empirical results recommends the worthiness of the intended antenna for handy UWB and UWB multiple-input multiple-output systems.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140577234","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}
{"title":"Bandpass filter with multiple selective absorptive stopbands for 28 GHz transmitters","authors":"Stefano Moscato, Steven Caicedo, Matteo Oldoni","doi":"10.1017/s1759078724000394","DOIUrl":"https://doi.org/10.1017/s1759078724000394","url":null,"abstract":"This manuscript presents a novel design for an absorptive bandpass filter for mm-wave applications, specifically the commercial FR2 spectrum. Three bands have been selected to be properly input matched with only one of them being the passband, where the insertion loss is minimized. The proposed approach relies on a multiplexer topology implemented through microstrip lines and on thin-film manufacturing process on alumina to shrink the footprint. Cascades of half-wavelength C-shape open-ended resonators are exploited to create the matched bands and define the filter’s selectivity. The selected passband spans from 26.5 to 28.5 GHz, with a measured maximum insertion loss of 3.05 dB for a −3 dB fractional bandwidth of 7.3%. Two absorptive bands are realized to match signals at 24 and 32.25 GHz. The alumina die footprint is 5500 × 3440 µm<jats:sup>2</jats:sup>, compatible with immediate integration within a mm-wave lineup.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576717","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}
{"title":"Bioinspired planar switched beam network using Butler matrix on a flexible substrate targeting multifaceted millimeter-wave applications","authors":"Balaka Biswas, Ayan Karmakar","doi":"10.1017/s1759078724000400","DOIUrl":"https://doi.org/10.1017/s1759078724000400","url":null,"abstract":"<p>This paper details the design and development of a planar switched beam network using 4 × 4 Butler matrix (BM) over a thin and flexible type biocompatible substrate. Four mils thick liquid crystal polymer (LCP) is used as a substrate here (<span>ϵ</span><span>r</span> = 2.92, tan<span>δ</span> = 0.002). The proposed design is centered at 28 GHz, targeting commercial millimeter-wave applications. Floral-shaped antenna with defective ground structures has been implemented as basic radiating elements. The whole structure is based on microstrip line configuration. The architecture occupies an area of 23.85 × 19.20 mm<span>2</span> over the LCP substrate. Individual components of the BM are detailed here, followed by a system analysis of the whole integrated structure. The present work also covers the electrical equivalent circuit modeling of the whole beam-forming network. The fabricated prototype offers better than 18 dB return losses at each input port for the desired frequency band with 6 dBi (max.) peak gain and 500 MHz bandwidth around the center frequency. Port-to-port isolation of better than 15 dB is achieved with this topology. Experimental and simulated results are in good agreement in all aspects. A comparative study is also chalked out to highlight the significance of the current research work with respect to alike earlier reported structures.</p>","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576725","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}
David Marzi, Erith Munoz Rios, Antonietta Sorriso, Fabio Dell’Acqua, Paolo Gamba
{"title":"Joint multitemporal SAR and optical mapping of urban changes","authors":"David Marzi, Erith Munoz Rios, Antonietta Sorriso, Fabio Dell’Acqua, Paolo Gamba","doi":"10.1017/s175907872400031x","DOIUrl":"https://doi.org/10.1017/s175907872400031x","url":null,"abstract":"<p>This paper presents a methodology designed to leverage multitemporal sequences of synthetic aperture radar (SAR) and multispectral data and automatically extract urban changes. The approach compares results using different radar and optical sensors, describing the advantages and drawbacks of using SAR data from the COnstellation of small Satellites for the Mediterranean basin Observation (COSMO)/SkyMed, SAtélite Argentino de Observación COn Microondas (SAOCOM), and Sentinel-1 constellations, as well as nighttime light data or Sentinel-2 images. Multiple indexes obtained from multispectral data are compared, too, and results obtained by an unsupervised clustering procedure are analyzed. The results show that using different datasets it is possible to obtain consistent results about different types of changes in urban areas (e.g., demolition, development, and densification) with different levels of spatial details.</p>","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140198094","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}
{"title":"An applicator for high-power rock comminution using microwave technology in the megawatt range","authors":"Yasin Alekajbaf, Dragos Dancila","doi":"10.1017/s1759078724000308","DOIUrl":"https://doi.org/10.1017/s1759078724000308","url":null,"abstract":"The mining industry is heavily dependent on energy-intensive processes, such as rock breakage, which leads to significant operational costs. This paper explores microwave-assisted rock breakage as an innovative method to enhance the efficiency of comminution within the mining industry. It introduces a system that employs a Klystron microwave power source with a maximum output of 7.5 MW, using a <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S1759078724000308_inline1.png\" /> <jats:tex-math>$mathrm{TM}_{010}$</jats:tex-math> </jats:alternatives> </jats:inline-formula> single-mode cavity at 3 GHz, to channel energy inside a specially designed rock cavity. The paper emphasizes the importance of designing an efficient microwave cavity for this system, focusing on the cavity’s design and simulation. Through both simulated results (using HFSS software) and experimental observations, the study reveals the promising application of microwave technology in the field of mining. The simulated frequency response of the designed cavity (<jats:italic>S</jats:italic><jats:sub>11</jats:sub>) is −22 dB, it demonstrates significant potential for reducing both energy consumption and associated costs. Additionally, the designed cavity is fabricated from aluminum and filled with polyether ether ketone material. The measured frequency response (<jats:italic>S</jats:italic><jats:sub>11</jats:sub>) of the cavity at 3 GHz is −17 dB.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140197834","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}
{"title":"An acceleration method employing sparse sensing matrix for fast analysis of the wide-angle electromagnetic problems based on compressive sensing","authors":"Qi Qi, Xinyuan Cao, Yi Liu, Meng Kong, Xiaojing Kuang, Mingsheng Chen","doi":"10.1017/s1759078724000291","DOIUrl":"https://doi.org/10.1017/s1759078724000291","url":null,"abstract":"<p>The electromagnetic scattering problem over a wide incident angle can be rapidly solved by introducing the compressive sensing theory into the method of moments, whose main computational complexity is comprised of two parts: a few calculations of matrix equations and the recovery of original induced currents. To further improve the method, a novel construction scheme of measurement matrix is proposed in this paper. With the help of the measurement matrix, one can obtain a sparse sensing matrix, and consequently the computational cost for recovery can be reduced by at least half. The scheme is described in detail, and the analysis of computational complexity and numerical experiments are provided to demonstrate the effectiveness.</p>","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140152148","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}