{"title":"Dual-narrowband bandpass filter with exact equations of scattering parameters","authors":"Masoud Najafi, Ali Reza Hazeri","doi":"10.1017/s1759078724000485","DOIUrl":"https://doi.org/10.1017/s1759078724000485","url":null,"abstract":"<p>In this article, a new microstrip dual-narrowband bandpass filter employing parallel-coupled transmission lines and open stubs is presented, investigated, and fabricated. The proposed dual-narrowband bandpass filter is analyzed and its exact scattering parameters are calculated, simulated, and measured. So, calculated scattering parameters offer a deep inside view of the performance of the proposed filter. To analyze the proposed filter, the even- and odd-mode excitation are utilized. The input impedance under even- and odd-mode excitation are achieved by transmission line theory and inserted in the scattering parameter equations. Finally, the accurate scattering parameters are derived and compared with simulation results. Simulation results prove the theoretical results. Then, an optimized proposed filter is fabricated and matched with simulation results. The center frequency bands are 4.5 and 6.8 GHz. The optimized filter occupies 0.12 <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240427055755777-0089:S1759078724000485:S1759078724000485_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$ times $</span></span></img></span></span> 0.096<span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240427055755777-0089:S1759078724000485:S1759078724000485_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$lambda _g^2$</span></span></img></span></span>, which is small. Its fractional bandwidth of the first and second passband are 1.5 and 2.5%, respectively. Furthermore, wide and strong rejection levels in the stopbands are offered. The structure of the proposed filter provides many freedoms to design. There is an agreement between experimental and simulation results.</p>","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"71 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140808725","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":"Design and fabrication of optically transparent transmitarrays using inkjet-printing technology","authors":"Han Chang, Fei-Peng Lai, Yen-Sheng Chen","doi":"10.1017/s1759078724000497","DOIUrl":"https://doi.org/10.1017/s1759078724000497","url":null,"abstract":"<p>This paper explores the use of inkjet-printing technology for transparent transmitarrays, presenting a viable alternative to traditional copper microwire counterparts. The study focuses on achieving high-gain performance crucial for wireless communication systems, with a particular emphasis on the fifth-generation (5G) millimeter-wave communication. Transparent transmitarrays leverage transparent conducting films and conductive mesh structures, overcoming opacity limitations and seamlessly integrating with urban architecture. In this paper, the inkjet-printing process is detailed for fabricating transmitarray apertures, highlighting the flexibility and precision in depositing nanosilver particles onto a glass substrate. The design intricacies involve optimizing feeding characteristics, determining unit cell structures, and constructing transmitarrays of various sizes. To validate the proposed technique, three different apertures (15 × 15, 20 × 20, and 25 × 25 unit cells) are constructed. The antenna performances are evaluated in terms of reflection coefficients, radiation efficiency, realized gain, and patterns, demonstrating the effectiveness of inkjet-printed transmitarrays. Comparative analysis with copper microwire counterparts is also conducted, validating the inkjet-printing technology for similar gain performance with added advantages of flexibility, compatibility with transparent substrates, and cost-effective manufacturing.</p>","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"33 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140808726","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}
Zhonghong Du, Xiaohui Zhang, Peiyu Qin, Yurong Pu, Xiaoli Xi
{"title":"Introduction of the orthogonal mode via the polarization conversion parasitic structure for the isolation enhancement of MIMO patch antennas","authors":"Zhonghong Du, Xiaohui Zhang, Peiyu Qin, Yurong Pu, Xiaoli Xi","doi":"10.1017/s1759078724000461","DOIUrl":"https://doi.org/10.1017/s1759078724000461","url":null,"abstract":"In this study, a high-isolation multiple-input multiple-output (MIMO) microstrip patch antenna (MPA), which utilizes an orthogonal mode cancellation method is proposed. This method employs TM<jats:sub>10</jats:sub> and TM<jats:sub>01</jats:sub> modes, which are simultaneously excited in the rectangular passive MPA. Initially, a rectangular decoupling structure featuring polarization rotation characteristics is designed. Further studies show that by loading the polarization conversion parasitic structure (PCPS), the electric field of the spatial coupling wave can be transformed from the <jats:italic>x</jats:italic>-polarized TM<jats:sub>10</jats:sub> mode to the <jats:italic>y</jats:italic>-polarized TM<jats:sub>01</jats:sub> mode. Therefore, TM<jats:sub>10</jats:sub> and TM<jats:sub>01</jats:sub> modes from the excited antenna and decoupling structure are concurrently coupled to the passive antenna, forming an evident weak-field region on the passive antenna. Placing the feeding probe of the passive MPA within the weak-field region prevents signal reception at the port. Consequently, this results in an extremely low mutual coupling of −49 dB at a resonant frequency of 5.8 GHz. Finally, a prototype of the proposed antenna is fabricated and tested, and the measured results closely match the simulated results. Additionally, it is observed that PCPS slightly influences the performance of the MIMO antenna.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"26 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140798811","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":"Breast tumors detection using multistatic microwave imaging with antipodal Vivaldi antennas utilizing DMAS and it-DMAS techniques","authors":"Athul O. Asok, Ayush Tripathi, Sukomal Dey","doi":"10.1017/s1759078724000436","DOIUrl":"https://doi.org/10.1017/s1759078724000436","url":null,"abstract":"This work presents a study where a sinusoidal corrugated antipodal Vivaldi antenna (SC-AVA) operating in the ultra-wideband (UWB) region is employed as a transducer for microwave imaging (MWI) of a cancerous breast. The functionality of the antenna within the UWB range is confirmed based on performance parameters like return loss, gain, radiation pattern, fidelity factor, and group delay. E-field distribution, H-field distribution, and near field directivity simulations in the presence of the breast phantom have also been carried out and reported. The practical application of the developed antenna for biomedical imaging is evaluated by measuring the specific absorption rate (SAR) readings at multiple frequencies within its operating range. The SAR readings are obtained from an electromagnetic simulator by modelling a realistic heterogeneous breast phantom with multiple embedded tumors, and placing them in close proximity to the transducer. The modelled SC-AVA is further utilized for imaging multiple tumors hidden inside the gland layer of the heterogeneous breast phantom developed in-house. The fabricated breast phantom is scanned using the in-house developed multistatic MWI setup. Based on the data obtained from the scanning setup the images are reconstructed using both the delay multiply and sum (DMAS) and iterative DMAS imaging algorithms. Furthermore, a comparison of the reconstructed images is done to check in which case the obtained images are closer to the fabricated breast phantom.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"10 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140627607","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":"SICL based Ka-band series SPDT switch for duplexer application","authors":"Saurabh Shukla, Soumava Mukherjee","doi":"10.1017/s1759078724000473","DOIUrl":"https://doi.org/10.1017/s1759078724000473","url":null,"abstract":"This paper presents a Ka-band series single-pole double-throw (SPDT) switch circuit realized in substrate-integrated coaxial line (SICL) environment for time division duplex operation. It is designed with a low-cost printed circuit board (PCB) technique. The size of the proposed circuit is <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S1759078724000473_inline1.png\" /> <jats:tex-math>$3.1lambda_{g} times 5.9lambda_{g}$</jats:tex-math> </jats:alternatives> </jats:inline-formula>, where <jats:italic>λ<jats:sub>g</jats:sub></jats:italic> is the guided wavelength at the center frequency of 27.75 GHz. In this circuit, a SICL-based SPDT switching circuit is proposed with radio frequency (RF) isolation network where the shunt connection of butterfly stubs is in an asymmetric stripline environment. The proposed circuit exhibits less than 2 dB insertion loss at 27–27.9 GHz and less than 2.5 dB insertion loss at 27–28.5 GHz. The design offers good impedance matching in the Transmit (Tx) and Receive (Rx) channels from the common Tx/Rx input channel, along with more than 24 dB isolation between ON and OFF state output channels. The proposed circuit is suitable for millimeter-wave communication systems.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"73 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140611931","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":"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":"34 1","pages":""},"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":"2D leaky-wave antenna with controlled direction of radiation in the azimuthal plane","authors":"Jan Machac, Milan Svanda, Vaclav Kabourek","doi":"10.1017/s1759078724000448","DOIUrl":"https://doi.org/10.1017/s1759078724000448","url":null,"abstract":"This paper presents a two-dimensional (2D) metasurface antenna array composed of mushroom cells coupled by thin slots in the top metallization. The antenna is fed through power dividers designed in substrate-integrated waveguide technology. The antenna structure is therefore designed in a fully up-to-date integrated version. The array shows beam steering in the azimuthal plane controlled by signal amplitudes fed into particular ports at the edges of the matrix. The main advantage of this antenna is no need to use phase shifters applied in standard 2D antenna arrays. Two antenna versions have been designed, fabricated, and experimentally tested. The beam can be steered within 360° (90°) in azimuth. The steering of the beam in elevation from backward to forward directions within 40° is done by changing frequency from 21 up to 23.8 GHz. This interval is reduced to 30° by exciting the antenna simultaneously at two adjacent ports at the same amplitude.","PeriodicalId":49052,"journal":{"name":"International Journal of Microwave and Wireless Technologies","volume":"124 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576738","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":"41 1","pages":""},"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":"8 1","pages":""},"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":"6 1","pages":""},"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}