Sreymom Noun, Sreyrong Chhit, Phally Phan, Jong-Sik Lim, Sang-Min Han, Dal Ahn, Youna Jang
{"title":"Development of a New Equivalent Circuit of DGS with Ideal Transformer","authors":"Sreymom Noun, Sreyrong Chhit, Phally Phan, Jong-Sik Lim, Sang-Min Han, Dal Ahn, Youna Jang","doi":"10.1155/2024/5534731","DOIUrl":"https://doi.org/10.1155/2024/5534731","url":null,"abstract":"<p>In this paper, a new equivalent circuit of a rectangular dumbbell-shaped defected ground structure (DGS) with an ideal transformer is proposed. The proposed circuit incorporates a parallel resistor in the DGS gap, enabling the extraction of the coupling coefficient of DGS occurring in the narrow line gaps. Both circuit simulations and measurements demonstrate excellent agreement, confirming excellent performance compared to the measured results. Unlike the conventional equivalent circuit, which consists only of the lumped element, this one has an accuracy of only DGS units. In the proposed circuit, an ideal transformer has higher accuracy for the DGS in parallel with a resistor. We observed that increasing the resistance of the parallel resistor on the DGS unit leads to a decrease in the coupling coefficient and, conversely, decreasing the resistance prompts an increase in the coupling coefficient. The goal of this study is to develop a new equivalent circuit for a DGS unit with the ideal transformer, especially to find the coupling coefficient that occurred in the DGS gap. Here, we analyzed that the structure of the DGS unit had a gap, and the coupling coefficient must be built into any value. To demonstrate the effectiveness of the proposed circuit, DGS was used to design and conduct fabrication and measurement. The advantages of the proposed circuit analysis of the DGS behavior can be used to develop the attenuation pole as a one-pole low-pass filter, paving the way for future applications and developments in microwave and RF circuit design.</p>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/5534731","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141487953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mutual Coupling Reduction in a Switched Beamforming Multilayer Antenna Array System","authors":"Emna Jebabli, Mohamed Hayouni, Fethi Choubani","doi":"10.1155/2024/3615181","DOIUrl":"https://doi.org/10.1155/2024/3615181","url":null,"abstract":"<p>In this paper, we present a millimeter-wave beamforming antenna array for the fifth generation (5G) of mobile networks and beyond. One of our priority objectives was to minimize the antenna array’s total physical size, by paying attention to avoid radiation performance degradation, such as bandwidth and efficiency. Another priority objective was to avoid mutual coupling (MC) between radiation elements and enhance the gain of the antenna to meet the requirements and challenges of the 5G. In these prospects, we have designed a 4 × 3 Chebyshev modified rectangular antenna array, engraved on the dielectric substrate of the top layer. The antenna array is powered across a 4 × 4 Butler matrix, engraved on the dielectric substrate of the bottom layer. The prototype overall size is 35.76 × 45.56 × 1.589 mm<sup>3</sup>. Hence, four switched main lobes pointed according to the angles -14°, +26°, -23° and +12°. The corresponded maximum gains at 28 GHz are 11.1, 10.5, 11, and 11.5 dB, respectively. Moreover, a reduction of the MC is ensured by using a CSRR metamaterial carved into the ground plane (GP) of the upper dielectric substrate layer. Experimental and simulation results concord well and show a multiband behavior at 26 GHz and in Ka-band. The impedance bandwidths are 1.5%, 2.7%, and 2.43% at 26, 28, and 40 GHz, respectively. A low MC, between the antenna array’s elements, is also achieved, and the levels of the transmission coefficients vary between -11 dB and -68 dB.</p>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/3615181","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Narrow Beam Gain Enhanced Wideband Antenna Array Using Slits, I-Slots, and L-Shaped Reflector for 5G Millimeter Wave Applications","authors":"Arun Kumar, Ganga Prasad Pandey","doi":"10.1155/2024/8919125","DOIUrl":"https://doi.org/10.1155/2024/8919125","url":null,"abstract":"<div>\u0000 <p>In this paper, a planar antenna structure-based compact high gain wideband antenna array is presented for 5G millimeter wave applications. The proposed array uses a 1-to-8 power divider to feed eight antenna elements arranged linearly. To enhance the gain, multiple slits and I-slots are placed on the ground plane and feeding network, respectively. To further improve the gain of the design, an L-shaped metallic reflector is positioned at the optimum distance. With a large 10 dB bandwidth of 35.93% from 22.6 to 32.5 GHz, the proposed antenna array operates in the two 5G bands of 26 GHz and 28 GHz. The proposed antenna array’s measured gain varies from 9.18 to 13.22 dBi which is higher than the gain of 6.60–10.45 dBi of the unmodified array for the entire operating range. The antenna array shows a narrow beamwidth of 6.25° in its <i>E</i>-plane and radiates in end-fire direction. The overall dimension of the proposed antenna array is 57 mm × 25.978 mm × 0.787 mm, which features a simple, compact design. This antenna can be used for millimeter wave application as it fulfills all the requirements of future 5G applications at 26 and 28 GHz bands.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/8919125","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141326717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compact Slot Microstrip Patch Antenna Loaded with Open Metal Cavity for Microwave Hyperthermia","authors":"Kun Hu, Qi Xiao, Kama Huang","doi":"10.1155/2024/9422872","DOIUrl":"https://doi.org/10.1155/2024/9422872","url":null,"abstract":"<div>\u0000 <p>Cancer is a significant disease that often results in severe side effects from traditional treatments. Microwave hyperthermia has emerged as a minimally invasive, highly effective, and low-toxicity treatment option that has gained widespread use in recent years. The primary objective of this study is to develop and assess a miniaturized slit patch antenna designed to operate at 2450 MHz for hyperthermia therapy. The octagonal antenna patch features four symmetrical slots to reduce its size, enhance directional radiation, and improve focusing and penetration depth. Additionally, a metal cavity is incorporated at the top of the antenna to create a gap between the antenna and the skin, allowing for skin heat dissipation, improved impedance matching, reduced outgoing radiation, and enhanced directional radiation. The performance of the antenna is assessed based on specific absorption rate (SAR), penetration depth (PD), and effective field size (EFS). Subsequently, the antenna is fabricated and tested in pork tissue, with the measured results demonstrating good agreement with the simulated outcomes.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/9422872","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141264666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of Hybrid Bandpass Filter Chips with High Selectivity and Wideband Using IPD and FBAR Technology","authors":"Keyan Li, Yongle Wu, Zhiguo Lai, Qinghua Yang, Weimin Wang, Yuhao Yang","doi":"10.1155/2024/9928016","DOIUrl":"https://doi.org/10.1155/2024/9928016","url":null,"abstract":"<div>\u0000 <p>A novel hybrid bandpass filter (BPF) with wideband and high selectivity is proposed in this paper. The hybrid BPF is composed of two film bulk acoustic resonator (FBAR) cells and three lumped component resonators realized by the integrated passive device (IPD) technology. The <i>ABCD</i> matrix to <i>S</i>-parameters matrix method is used to calculate the frequency response of the BPF. Moreover, the expressions of transmission zeros (TZs) have been extracted. In the design process, an iterative design approach is proposed to improve the circuit and layout of the hybrid filter based on the packaged acoustic-electric hybrid simulation effect. Finally, two parts of the filter are packaged based on the flip-chip method, and two prototypes for the BPF are measured. The measured results of two chips with 3 dB fractional bandwidth of 13.7% and 15.8% are designed and fabricated, which verifies the validity of the proposed design principle.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/9928016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141246043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stub Asymmetry-Enabled Self-Phase-Shift Circularly Polarized Antenna under Dual-Mode Resonance","authors":"Shan-Shan Gu, Wen-Jun Lu, Fei-Yan Ji, Lei Zhu","doi":"10.1155/2024/3884672","DOIUrl":"https://doi.org/10.1155/2024/3884672","url":null,"abstract":"<div>\u0000 <p>In this article, a novel design approach to wideband dual-mode resonant circularly polarized (CP) antenna is advanced. An analytical design approach with low complexity as supported by a set of closed-form formulas is presented. Thus, the wideband dual-mode CP characteristics can be forward predicted and simply realized by incorporating stub asymmetry-enabled self-phase-shift dipoles and unequal feeding branches. At first, stubs are employed to broaden the impedance bandwidth by simultaneously exciting dual resonant modes. Then, the phase quadrature and equal magnitude conditions for wideband CP can be automatically realized by incorporating unequal Y-shaped microstrip branches and asymmetric slotline stubs. Finally, the coincidence between the simulated and measured results of the fabricated prototype antenna further confirms the feasibility of the design approach. It is shown that the presented antenna can exhibit an impedance bandwidth of 20.1% and a 3 dB axial ratio bandwidth of 16.3% in the boresight direction.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/3884672","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141245920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Frequency-Tunable SIW Band-Reject Filter with Increased Fundamental Mode Bandwidth for Spectrum Underlay Cognitive Radio","authors":"Sreenath Reddy Thummaluru, Rajkishor Kumar, Raghvendra Kumar Chaudhary","doi":"10.1155/2024/4303470","DOIUrl":"10.1155/2024/4303470","url":null,"abstract":"<div>\u0000 <p>This paper presents the design of a frequency-tunable substrate-integrated waveguide (SIW) band-reject filter, specifically for spectrum underlay cognitive radio operation. The proposed filter has a simple tuning circuit but provides a wide frequency tuning range from 2.9 to 4.4 GHz (41%). The second resonant mode has been suppressed using a simple quadrature coupling; hence, the fundamental mode bandwidth of the filter has been increased from 2.08 GHz to 3.36 GHz. Due to its wide tuning range, simple tuning circuit, and increased fundamental mode bandwidth, the proposed filter is greatly important in underlay cognitive radio construction. The second-order filter has also been developed, and its performance is analyzed with both simulation and measurement. It gives a tunable bandwidth of 41%, an insertion loss of more than 10 dB, and a fundamental mode bandwidth of 3.36 GHz. The filter performance is also analyzed after connecting it to the standard horn antenna. Finally, from the total efficiency plots, it has been concluded that the proposed filter achieves all the above advantages with a low-lossy nature.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/4303470","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141106632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and Tensor Impedance Analysis of 4 × 4 Isotropic Homogeneous Metasurface-Backed Slotted Dual-Layered Bio-Superstrate-Loaded MPA","authors":"Swarnadipto Ghosh, Samik Chakraborty, Ayona Chakraborty, Bhaskar Gupta","doi":"10.1155/2024/8815739","DOIUrl":"10.1155/2024/8815739","url":null,"abstract":"<div>\u0000 <p>A 4 × 4 Isotropic Homogeneous Metasurface (IHM) backed, rectangular slotted dual-layered triband microstrip patch antenna (MPA) is proposed in this article. A detailed mathematical way to analyze the tensor surface impedance matrix (TSIM) of the proposed 4 × 4 IHM and slotted patch is demonstrated. The proposed IHM-backed MPA has a triband even-mode resonance at <i>f</i><sub>r0</sub> = 2.45 GHz, 2<i>f</i><sub>r0</sub> = 5.4 GHz, and 4<i>f</i><sub>r0</sub> = 7.7 GHz. A better and more accurate estimation of bio-superstrate loading effect for triband resonance is employed using the human skin (<i>ε</i><sub>r</sub> = 52.79, <i>σ</i><sub>s</sub> = 1.39) and blood (<i>ε</i><sub>r</sub> = 52.8, <i>σ</i><sub>s</sub> = 1.23) layer on the top of dual-layered metasurface-backed slotted MPA. TSIM characterization is observed for both blood- and skin layer-loaded dual-layered metasurface-backed slotted MPA. Chicken breast (<i>ε</i><sub>r</sub> = 55.2, <i>σ</i><sub>s</sub> = 1.49, and tan<i>δ</i> = 0.325) with blood (<i>ε</i><sub>r</sub> = 58.2, <i>σ</i><sub>s</sub> = 2.59, and tan<i>δ</i> = 0.364) is loaded onto fabricated dual-layered structure to verify numerically modeled estimation. A closed form triband, even-order resonance mode (i.e., <i>f</i><sub>r0</sub>, 2<i>f</i><sub>r0</sub>, and 4<i>f</i><sub>r0</sub>) estimation based on dielectric superstrate thickness (<i>H</i><sub>s</sub>) is numerically established using MATLAB solver. Complete measurement setup with simulated vs. measured results is compared in this article.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/8815739","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141124874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermal Characteristic Investigation for a Multichip Module Based on APDL","authors":"Qian Lin, Peng-Fei Zhao, Rui-lan Yang, Hai-feng Wu","doi":"10.1155/2024/2028369","DOIUrl":"10.1155/2024/2028369","url":null,"abstract":"<div>\u0000 <p>Aiming at the failure problems of integrated circuit (IC) caused by higher package density, thinner package, and more heat sources, taking a multichip module (MCM) for receiver front end as an example, the 3-D model is established based on ANSYS Parametric Design Language (APDL). Then, the steady-state thermal analysis is achieved to complete the automatic calculation of thermal characteristic. As a result, the temperature, stress, and deformation are investigated in details, and its temperature distribution, stress distribution, deformation distribution, and reliability variations of this MCM under different powers and temperatures can be obtained. This can provide important theoretical reference for the chip package optimization. Different from other studies which only focus on temperature or stress, it is more comprehensive and systematic for the thermal characteristic analysis of MCM. Meanwhile, this MCM is also representative for wireless communication system. It is of great significance to optimize the layout design and improve the thermal characteristic for IC.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/2028369","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140690637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design of Cross-Coupled Bandpass Filters with Flexible Coupling via Half-Mode Substrate-Integrated Waveguide","authors":"Qianwen Liu, Lei Zhu","doi":"10.1155/2024/3897878","DOIUrl":"10.1155/2024/3897878","url":null,"abstract":"<div>\u0000 <p>In this article, a simple approach for achievement of flexible coupling is presented based on the half-mode substrate-integrated waveguide (HMSIW). Since both electric and magnetic fields vary along the magnetic wall of the HMSIW, there exists mixed coupling between two adjacent HMSIWs. In this context, only by adjusting the width of the coupling slot at specific regions, both coupling property and strength can be conveniently controlled. Besides, as the coupling slot possesses the merits of simple structure and high flexibility, it is also expected to achieve desired couplings between multimode resonators. For demonstration, three cross-coupled bandpass filters (BPFs) with different kinds of frequency responses are constructed based on the typical cascaded trisection coupling topology by mixing one SIW and two HMSIWs, including two single-band and one dual-band designs. All measured results are highly consistent with the simulated ones, validating that the HMSIW not only has the inherent advantage of smaller size than the conventional SIW counterparts but also possesses unique feature in providing flexible coupling without extra circuit.</p>\u0000 </div>","PeriodicalId":54944,"journal":{"name":"International Journal of RF and Microwave Computer-Aided Engineering","volume":"2024 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/2024/3897878","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140738368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}