Pub Date : 2024-11-19DOI: 10.1109/LAWP.2024.3502788
Ze Yu;Chang Chen;Wei-Dong Chen;Xiang Zhang;Xiao-Lin Zhang
The electronically steered phased array (ESPA), which is composed of periodic antenna elements, usually uses subarrays with large spacing to lower system complexity and cost. This kind of phased subarray (PSA) has a serious problem with grating lobes while beam scanning. A prephased metalens PSA (PMPSA) that combines prephases and metalens for modifying the transmitting phases is proposed. Further, the limited random phase method (LRPM) for randomizing the feeding phases and cooperating with prephased metalens to suppress the grating lobes is also proposed. In comparison to a PSA with the same parameters, the results demonstrate that the PMPSA can achieve a much better SLL, especially at wide scanning angles. Finally, calculated and simulated results show that a 16 × 16-unit phased array with 2 × 2-unit subarrays can achieve an SLL below −9.9 dB in 2D scanning using the limited random phase method.
{"title":"A Novel Grating Lobe Suppression Method for Large-Spacing Phased Arrays Using Prephased Metalens and Limited Random Phase","authors":"Ze Yu;Chang Chen;Wei-Dong Chen;Xiang Zhang;Xiao-Lin Zhang","doi":"10.1109/LAWP.2024.3502788","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3502788","url":null,"abstract":"The electronically steered phased array (ESPA), which is composed of periodic antenna elements, usually uses subarrays with large spacing to lower system complexity and cost. This kind of phased subarray (PSA) has a serious problem with grating lobes while beam scanning. A prephased metalens PSA (PMPSA) that combines prephases and metalens for modifying the transmitting phases is proposed. Further, the limited random phase method (LRPM) for randomizing the feeding phases and cooperating with prephased metalens to suppress the grating lobes is also proposed. In comparison to a PSA with the same parameters, the results demonstrate that the PMPSA can achieve a much better SLL, especially at wide scanning angles. Finally, calculated and simulated results show that a 16 × 16-unit phased array with 2 × 2-unit subarrays can achieve an SLL below −9.9 dB in 2D scanning using the limited random phase method.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"444-448"},"PeriodicalIF":3.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-19DOI: 10.1109/LAWP.2024.3502398
Shilong Tan;Shixing Yu;Na Kou
In this letter, we propose using the conical conformal array antenna to launch the steering electromagnetic orbital angular momentum (OAM) vortex waves. First, the theoretical calculation method for generating the steering OAM beams using conical array antenna is deduced and the formula of compensated phase shift for each antenna unit located in the conical array is derived. In addition, a polarization correction approach is proposed to achieve better radiation characteristics of the OAM vortex beam. Next, a prototype of a conical conformal array antenna, which consists of 114 U-slot microstrip patch antennas, is fabricated and experimentally verified. The measured results indicate that using the conical array antenna to launch steering OAM vortex beams directed at the elevation angle of 0° to 60° can prevent significant distortion and guarantee high mode purity even though the scanning angle becomes large. This could serve as a reference for potential future applications of electromagnetic vortex communication on a conformal carrier.
{"title":"Generating Steering Orbital Angular Momentum Vortex Beams Using Conical Conformal Array Antenna","authors":"Shilong Tan;Shixing Yu;Na Kou","doi":"10.1109/LAWP.2024.3502398","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3502398","url":null,"abstract":"In this letter, we propose using the conical conformal array antenna to launch the steering electromagnetic orbital angular momentum (OAM) vortex waves. First, the theoretical calculation method for generating the steering OAM beams using conical array antenna is deduced and the formula of compensated phase shift for each antenna unit located in the conical array is derived. In addition, a polarization correction approach is proposed to achieve better radiation characteristics of the OAM vortex beam. Next, a prototype of a conical conformal array antenna, which consists of 114 U-slot microstrip patch antennas, is fabricated and experimentally verified. The measured results indicate that using the conical array antenna to launch steering OAM vortex beams directed at the elevation angle of 0° to 60° can prevent significant distortion and guarantee high mode purity even though the scanning angle becomes large. This could serve as a reference for potential future applications of electromagnetic vortex communication on a conformal carrier.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"429-433"},"PeriodicalIF":3.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anomalous reflection efficiency is limited in the case of large deflection angles. In this letter, we design a metagrating that can maintain high efficiency in an incident angle range of 10°–60° with a fractional bandwidth up to 55.3%. By adjusting the period of the metagrating, only the 0th and −1st-diffraction orders exist under oblique incidence. The unit cell of the metagrating consists of two metal rings, which exhibit a π phase difference and can shut down the 0th-order diffraction mode. Therefore, only the −1st-order anomalous reflection can be achieved under oblique incidence conditions. Simulated and experimental results demonstrate that the proposed metagrating can achieve anomalous reflection at broadband and large angles. Furthermore, a multifunctional metagrating can be implemented by redesigning the metal rings, which have various functions of anomalous reflection, polarization selection, and multibeam generation.
{"title":"Broadband and Wide-Incident-Angle Anomalous Reflection Multifunctional Metagrating","authors":"Wenyu Gao;Yahong Liu;Xin Zhou;Lijun Ding;Xiaoyong Yang;Peng Li;Jintao Zhang;Kun Song;Zhenfei Li;Xiaopeng Zhao","doi":"10.1109/LAWP.2024.3502165","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3502165","url":null,"abstract":"Anomalous reflection efficiency is limited in the case of large deflection angles. In this letter, we design a metagrating that can maintain high efficiency in an incident angle range of 10°–60° with a fractional bandwidth up to 55.3%. By adjusting the period of the metagrating, only the 0th and −1st-diffraction orders exist under oblique incidence. The unit cell of the metagrating consists of two metal rings, which exhibit a π phase difference and can shut down the 0th-order diffraction mode. Therefore, only the −1st-order anomalous reflection can be achieved under oblique incidence conditions. Simulated and experimental results demonstrate that the proposed metagrating can achieve anomalous reflection at broadband and large angles. Furthermore, a multifunctional metagrating can be implemented by redesigning the metal rings, which have various functions of anomalous reflection, polarization selection, and multibeam generation.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"419-423"},"PeriodicalIF":3.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-19DOI: 10.1109/LAWP.2024.3502256
Long Li;Qingxiu Ma;Zhao Wu;Jiajun Liang
This letter proposes a tri-polarization reconfigurable diversity antenna with integrated filtering functions based on ellipse-shaped metasurfaces (MTS). The antenna consists of three layers: the feedline layer, the coupled aperture layer, and the MTS layer. To get a low-frequency radiation null, the complementary split ring resonators (CSRRs) are loaded on the coupled aperture layer, utilizing resonant characteristics. Furthermore, a nonradiation characteristics mode of the MTS is excited for a high-frequency radiation null. Thus, a filtering function of the proposed antenna is provided. Besides, there are three coupled slots on the aperture layer. Six sets of PIN diodes are inserted on the microstrip and coupled aperture. Through controlling the PIN diode, the polarization reconfigurability is obtained by choosing different coupled slots and changing the associated electric field vector. Eventually, the proposed antenna could switch between linear polarization (LP), left-hand circular polarization (LHCP), and right-hand circular polarization. In the experiment, the proposed antenna shows a wide −10 dB impedance bandwidth (IMBW) of 29% and 29.5% for LP and CP modes. While operating in CP modes, the antenna has a wide measured 3 dB axial ratio (AR) bandwidth of 29%. Meanwhile, the out-of-band radiation suppression level in low frequency is more than 30 dB and 20 dB for LP and CP modes, respectively.
{"title":"Polarization-Reconfigurable Enhanced Ellipse-Shaped Metasurfaces Antenna With Integrated Filtering Functions","authors":"Long Li;Qingxiu Ma;Zhao Wu;Jiajun Liang","doi":"10.1109/LAWP.2024.3502256","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3502256","url":null,"abstract":"This letter proposes a tri-polarization reconfigurable diversity antenna with integrated filtering functions based on ellipse-shaped metasurfaces (MTS). The antenna consists of three layers: the feedline layer, the coupled aperture layer, and the MTS layer. To get a low-frequency radiation null, the complementary split ring resonators (CSRRs) are loaded on the coupled aperture layer, utilizing resonant characteristics. Furthermore, a nonradiation characteristics mode of the MTS is excited for a high-frequency radiation null. Thus, a filtering function of the proposed antenna is provided. Besides, there are three coupled slots on the aperture layer. Six sets of PIN diodes are inserted on the microstrip and coupled aperture. Through controlling the PIN diode, the polarization reconfigurability is obtained by choosing different coupled slots and changing the associated electric field vector. Eventually, the proposed antenna could switch between linear polarization (LP), left-hand circular polarization (LHCP), and right-hand circular polarization. In the experiment, the proposed antenna shows a wide −10 dB impedance bandwidth (IMBW) of 29% and 29.5% for LP and CP modes. While operating in CP modes, the antenna has a wide measured 3 dB axial ratio (AR) bandwidth of 29%. Meanwhile, the out-of-band radiation suppression level in low frequency is more than 30 dB and 20 dB for LP and CP modes, respectively.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"424-428"},"PeriodicalIF":3.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-18DOI: 10.1109/LAWP.2024.3500029
Binchao Zhang;Kuan Lu;Pengfei Wang;Yibei Zhang;Bingyan Zhou;Cheng Jin;Baihong Chi
In this letter, an integrated low radar cross section (RCS) circularly polarized (CP) antenna based on multimode metasurface is proposed. The mode resources of the metasurface are fully utilized, and each mode are endowed with various functions by different excitation methods. As a result, the stealth and radiation properties are integrated into a simple structure. A specific design is carefully elaborated to illustrate this route. First, a rectangular patch is diagonally placed to perform wideband polarization rotation, which has three distinct resonant modes. Next, the polarization rotation of the middle mode is destroyed by central slotting, which is utilized as the antenna's operating mode. Finally, proper feeding techniques are used to excite the middle mode to produce a efficient radiation. As an example, an 8 × 8 metasurface-based integrated low RCS CP antenna array is designed and fabricated, which achieves both reliable radiation performance and effective RCS reduction simultaneously. Both simulated and measured results verify the effectiveness of the proposed method.
{"title":"Integrated Low RCS Circularly Polarized Antenna Based on Multimode Metasurface","authors":"Binchao Zhang;Kuan Lu;Pengfei Wang;Yibei Zhang;Bingyan Zhou;Cheng Jin;Baihong Chi","doi":"10.1109/LAWP.2024.3500029","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3500029","url":null,"abstract":"In this letter, an integrated low radar cross section (RCS) circularly polarized (CP) antenna based on multimode metasurface is proposed. The mode resources of the metasurface are fully utilized, and each mode are endowed with various functions by different excitation methods. As a result, the stealth and radiation properties are integrated into a simple structure. A specific design is carefully elaborated to illustrate this route. First, a rectangular patch is diagonally placed to perform wideband polarization rotation, which has three distinct resonant modes. Next, the polarization rotation of the middle mode is destroyed by central slotting, which is utilized as the antenna's operating mode. Finally, proper feeding techniques are used to excite the middle mode to produce a efficient radiation. As an example, an 8 × 8 metasurface-based integrated low RCS CP antenna array is designed and fabricated, which achieves both reliable radiation performance and effective RCS reduction simultaneously. Both simulated and measured results verify the effectiveness of the proposed method.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"394-398"},"PeriodicalIF":3.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-18DOI: 10.1109/LAWP.2024.3501977
David Toribio;Arno Thielens
The increased exposure of insects to radio frequency electromagnetic fields (RF-EMFs) may have an impact on their health. The RF-EMF absorbed power in certain insects is considerably higher in the range of 6 GHz to 300 GHz, due to more comparable wavelengths to their size. Likewise, in this range, the near-field interactions between antennas' and certain insects can significantly affect antennas' performance. Thus, in this work, the volume and frequency dependencies of the RF-EMF absorbed power in various insects is evaluated in the range of 6 GHz to 120 GHz, at a fixed separation distance of 10 cm between the insects and a dipole antenna. Moreover, the effect of these insects on the dipoles' performance is assessed. To this aim, numerical simulations using finite-difference time-domain (FDTD) were performed on insect models obtained through micro-CT scanning. These simulation results showed an average absorbed power of 3.1 $pm$ 2.7 mW/W at 6 GHz and of 3.4 $pm$ 2.8 mW/W at 120 GHz. Also, they revealed that the absorbed power increases with increasing insect volume at an approximate rate of $text{2.5}:{mu text{W}}/{text{W}cdot text{mm}^{3}}$ at 6 GHz, and of $text{1.2}:{mu text{W}}/{text{W}cdot text{mm}^{3}}$ at 120 GHz, and that this rate of increase lowers with increasing frequency. Furthermore, results showed that the dipoles' gain pattern have a dependency on the insects' volume with a stronger dependency for higher frequencies.
{"title":"Radio Frequency Electromagnetic Field Exposure of Insects at 10 cm From an Antenna","authors":"David Toribio;Arno Thielens","doi":"10.1109/LAWP.2024.3501977","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3501977","url":null,"abstract":"The increased exposure of insects to radio frequency electromagnetic fields (RF-EMFs) may have an impact on their health. The RF-EMF absorbed power in certain insects is considerably higher in the range of 6 GHz to 300 GHz, due to more comparable wavelengths to their size. Likewise, in this range, the near-field interactions between antennas' and certain insects can significantly affect antennas' performance. Thus, in this work, the volume and frequency dependencies of the RF-EMF absorbed power in various insects is evaluated in the range of 6 GHz to 120 GHz, at a fixed separation distance of 10 cm between the insects and a dipole antenna. Moreover, the effect of these insects on the dipoles' performance is assessed. To this aim, numerical simulations using finite-difference time-domain (FDTD) were performed on insect models obtained through micro-CT scanning. These simulation results showed an average absorbed power of 3.1 <inline-formula><tex-math>$pm$</tex-math></inline-formula> 2.7 mW/W at 6 GHz and of 3.4 <inline-formula><tex-math>$pm$</tex-math></inline-formula> 2.8 mW/W at 120 GHz. Also, they revealed that the absorbed power increases with increasing insect volume at an approximate rate of <inline-formula><tex-math>$text{2.5}:{mu text{W}}/{text{W}cdot text{mm}^{3}}$</tex-math></inline-formula> at 6 GHz, and of <inline-formula><tex-math>$text{1.2}:{mu text{W}}/{text{W}cdot text{mm}^{3}}$</tex-math></inline-formula> at 120 GHz, and that this rate of increase lowers with increasing frequency. Furthermore, results showed that the dipoles' gain pattern have a dependency on the insects' volume with a stronger dependency for higher frequencies.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"414-418"},"PeriodicalIF":3.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This letter proposes a bilayer transmissive Huygens metasurface with an independent phase response for two orthogonal polarizations to generate two distinct modes of orbital angular momentum (OAM) beams. The performance of the proposed unit cell is comprehensively investigated, and its efficiency in the near field is verified through an analytical approach. Then, the necessary theories for realizing converged OAM beams by merging the lens and OAM phase distributions are inclusively elaborated. Moreover, a dual-polarized quad-ridged open-ended waveguide antenna is designed to illuminate the metasurface. Ultimately, two scenarios are explored through the designed surface. The first strategy generates the second ($l_{x}=2$) and third ($l_{y}=3$) modes of the OAM beams in the x- and y-polarizations, respectively, while the second strategy produces modes $l_{x}=0$ and $l_{y}=2$ in two orthogonal polarizations. It appears that the suggested configuration managed to obtain a respectable level of agreement between simulation and measurement results.
{"title":"Anisotropic Bilayer Transmissive Huygens Metasurface for Generating Multi-OAM Beams With Orthogonal Modes and Polarizations","authors":"Rasoul Ebrahimzadeh;Larbi Talbi;Mohammad Yousefzadeh;Khelifa Hettak","doi":"10.1109/LAWP.2024.3501371","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3501371","url":null,"abstract":"This letter proposes a bilayer transmissive Huygens metasurface with an independent phase response for two orthogonal polarizations to generate two distinct modes of orbital angular momentum (OAM) beams. The performance of the proposed unit cell is comprehensively investigated, and its efficiency in the near field is verified through an analytical approach. Then, the necessary theories for realizing converged OAM beams by merging the lens and OAM phase distributions are inclusively elaborated. Moreover, a dual-polarized quad-ridged open-ended waveguide antenna is designed to illuminate the metasurface. Ultimately, two scenarios are explored through the designed surface. The first strategy generates the second (<inline-formula><tex-math>$l_{x}=2$</tex-math></inline-formula>) and third (<inline-formula><tex-math>$l_{y}=3$</tex-math></inline-formula>) modes of the OAM beams in the <italic>x</i>- and <italic>y</i>-polarizations, respectively, while the second strategy produces modes <inline-formula><tex-math>$l_{x}=0$</tex-math></inline-formula> and <inline-formula><tex-math>$l_{y}=2$</tex-math></inline-formula> in two orthogonal polarizations. It appears that the suggested configuration managed to obtain a respectable level of agreement between simulation and measurement results.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"409-413"},"PeriodicalIF":3.7,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-15DOI: 10.1109/LAWP.2024.3500079
Dajiang Li;Hao-Lan Zhou;Kun-Zhi Hu;Zhiyuan Chen;Yaqing Yu;Dong Yan
In this letter, the single-layer wideband and dual-band endfire filtering antennas with high front-to-back ratio (FTBR) are developed. The wideband design mainly consists of five parts: the double-sided parallel-strip line (DSPSL) feeding structure, two sets of driven elements, the parasitic strips, the directors, and the U-shaped ground. Herein, the adoption of two sets of driven elements realizes a natural lower radiation null, while the incorporation of parasitic strips facilitates an upper radiation null. The dual-band design is achieved by simply loading the additional longer parasitic strips onto the wideband design, which creates a middle radiation null between the two bands. Including the elaborated ground and the directors effectively enhances the FTBR of both designs. For verification, prototypes were manufactured and measured, and the measured results are in good agreement with the simulated ones. The overlapped bandwidth (|S11| ≤ −10 dB and FTBR ≥ 15 dB) of the wideband design reaches 54.3%, and that of the dual-band design is 33.6% and 15.5%, respectively. Moreover, both designs exhibit good frequency selectivity with multiple radiation nulls.
{"title":"Single-Layer Wideband and Dual-Band Endfire Filtering Antennas With High Front-to-Back Ratio","authors":"Dajiang Li;Hao-Lan Zhou;Kun-Zhi Hu;Zhiyuan Chen;Yaqing Yu;Dong Yan","doi":"10.1109/LAWP.2024.3500079","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3500079","url":null,"abstract":"In this letter, the single-layer wideband and dual-band endfire filtering antennas with high front-to-back ratio (FTBR) are developed. The wideband design mainly consists of five parts: the double-sided parallel-strip line (DSPSL) feeding structure, two sets of driven elements, the parasitic strips, the directors, and the U-shaped ground. Herein, the adoption of two sets of driven elements realizes a natural lower radiation null, while the incorporation of parasitic strips facilitates an upper radiation null. The dual-band design is achieved by simply loading the additional longer parasitic strips onto the wideband design, which creates a middle radiation null between the two bands. Including the elaborated ground and the directors effectively enhances the FTBR of both designs. For verification, prototypes were manufactured and measured, and the measured results are in good agreement with the simulated ones. The overlapped bandwidth (|<italic>S</i><sub>11</sub>| ≤ −10 dB and FTBR ≥ 15 dB) of the wideband design reaches 54.3%, and that of the dual-band design is 33.6% and 15.5%, respectively. Moreover, both designs exhibit good frequency selectivity with multiple radiation nulls.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"399-403"},"PeriodicalIF":3.7,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-14DOI: 10.1109/LAWP.2024.3498446
Xinyu Zhu;Xing Zhao;Zhiming Liu;Minghao Hu;Haoming Ying;Qishen Huang;Bingying Li
A novel Fabry–Perot resonator antenna (FPRA) with wideband gain enhancement and frequency scanning characteristics is proposed. The gain of original monopole-type radiation patch exhibits a significant fluctuation in the operating frequency range, resulting in a narrow 3 dB gain bandwidth. Hence, two types of partially reflecting surface (PRS) units with appropriate reflection coefficients that can compensate the gain fluctuation of original radiation patch are designed. These PRS units improve the gain amplitude and flatness simultaneously, which would bring a much larger gain-bandwidth product (GBP). Meanwhile, the proposed FPRA also has a frequency scanning property due to the phase difference of adjacent incident waves to PRS that varies with the operating frequency. The measured results indicate that the proposed FPRA has a 10 dB impedance bandwidth of 7.1 GHz to 25.5 GHz (112.9%) and a 3 dB gain bandwidth of 7.42 GHz to 23.12 GHz (102.8%). It has a maximum gain of 15.73 dBi at 13.5 GHz and a large GBP per unit area of 1764.4, realized with a simple and compact structure. In 7.42 GHz to 13.9 GHz, it also illustrates a frequency scanning angle of approximately 0$^{circ }$–$43^{circ }$.
{"title":"A Fabry–Perot Resonator Antenna With Wideband Gain Enhancement and Frequency Scanning Characteristics","authors":"Xinyu Zhu;Xing Zhao;Zhiming Liu;Minghao Hu;Haoming Ying;Qishen Huang;Bingying Li","doi":"10.1109/LAWP.2024.3498446","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3498446","url":null,"abstract":"A novel Fabry–Perot resonator antenna (FPRA) with wideband gain enhancement and frequency scanning characteristics is proposed. The gain of original monopole-type radiation patch exhibits a significant fluctuation in the operating frequency range, resulting in a narrow 3 dB gain bandwidth. Hence, two types of partially reflecting surface (PRS) units with appropriate reflection coefficients that can compensate the gain fluctuation of original radiation patch are designed. These PRS units improve the gain amplitude and flatness simultaneously, which would bring a much larger gain-bandwidth product (GBP). Meanwhile, the proposed FPRA also has a frequency scanning property due to the phase difference of adjacent incident waves to PRS that varies with the operating frequency. The measured results indicate that the proposed FPRA has a 10 dB impedance bandwidth of 7.1 GHz to 25.5 GHz (112.9%) and a 3 dB gain bandwidth of 7.42 GHz to 23.12 GHz (102.8%). It has a maximum gain of 15.73 dBi at 13.5 GHz and a large GBP per unit area of 1764.4, realized with a simple and compact structure. In 7.42 GHz to 13.9 GHz, it also illustrates a frequency scanning angle of approximately 0<inline-formula><tex-math>$^{circ }$</tex-math></inline-formula>–<inline-formula><tex-math>$43^{circ }$</tex-math></inline-formula>.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"389-393"},"PeriodicalIF":3.7,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-11-13DOI: 10.1109/LAWP.2024.3496903
Qing Yu;Xianzhong Chen;Qingwen Hou;Jie Zhang
Microwave radars have been utilized as detectors within blast furnaces to accomplish the measurement of the surface shape of the furnace burden. However, the additional physical information contained in the radar echoes has not yet been fully explored. The electromagnetic scattering model of the burden surface can serve as the theoretical foundation for the inversion of radar data. In this letter, first, the statistical values of the roughness parameters of the burden surface are obtained by measuring typical samples. Second, an equivalent dielectric constant model is proposed for the coexistence of coke, ore, water, and gas on the burden surface. Finally, the back-scattering coefficient of the burden surface was calculated by the integral equation method (IEM) based on the roughness parameters and geometric characteristics of the burden surface. The effects of charge size and volume fractions of ore, coke, and water on the electromagnetic scattering characteristics were analyzed. The experimental results indicate that for the blast furnace burden surface where coke, ore, and gas coexist, when the angle of incidence is 30° and the root mean square height is less than 0.03 m, the back-scattering is enhanced as the roughness of the burden surface increases. In comparison, for the surface of coke material, the moisture content has a greater impact on electromagnetic scattering than the incorporation of ore with the same volume fraction.
{"title":"Electromagnetic Scattering of Blast Furnace Burden Surface With Stochastic Properties","authors":"Qing Yu;Xianzhong Chen;Qingwen Hou;Jie Zhang","doi":"10.1109/LAWP.2024.3496903","DOIUrl":"https://doi.org/10.1109/LAWP.2024.3496903","url":null,"abstract":"Microwave radars have been utilized as detectors within blast furnaces to accomplish the measurement of the surface shape of the furnace burden. However, the additional physical information contained in the radar echoes has not yet been fully explored. The electromagnetic scattering model of the burden surface can serve as the theoretical foundation for the inversion of radar data. In this letter, first, the statistical values of the roughness parameters of the burden surface are obtained by measuring typical samples. Second, an equivalent dielectric constant model is proposed for the coexistence of coke, ore, water, and gas on the burden surface. Finally, the back-scattering coefficient of the burden surface was calculated by the integral equation method (IEM) based on the roughness parameters and geometric characteristics of the burden surface. The effects of charge size and volume fractions of ore, coke, and water on the electromagnetic scattering characteristics were analyzed. The experimental results indicate that for the blast furnace burden surface where coke, ore, and gas coexist, when the angle of incidence is 30° and the root mean square height is less than 0.03 m, the back-scattering is enhanced as the roughness of the burden surface increases. In comparison, for the surface of coke material, the moisture content has a greater impact on electromagnetic scattering than the incorporation of ore with the same volume fraction.","PeriodicalId":51059,"journal":{"name":"IEEE Antennas and Wireless Propagation Letters","volume":"24 2","pages":"369-373"},"PeriodicalIF":3.7,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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