Pub Date : 2025-11-04DOI: 10.1109/TTHZ.2025.3623809
{"title":"IEEE Microwave Theory and Techniques Society Information","authors":"","doi":"10.1109/TTHZ.2025.3623809","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3623809","url":null,"abstract":"","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"15 6","pages":"C2-C2"},"PeriodicalIF":3.9,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11225872","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-04DOI: 10.1109/TTHZ.2025.3617955
Thomas Kürner;David A. Humphreys;Thomas Kleine-Ostmann
{"title":"Editorial on the Special Section on “Metrology for THz Communications”","authors":"Thomas Kürner;David A. Humphreys;Thomas Kleine-Ostmann","doi":"10.1109/TTHZ.2025.3617955","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3617955","url":null,"abstract":"","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"15 6","pages":"949-950"},"PeriodicalIF":3.9,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11225912","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A quasi-optical (QO) test bench was designed, simulated, and calibrated for characterizing all four S-parameters of devices in the 220–330 GHz (WR3.4) frequency range, from room temperature down to 4.8 K. Quasioptical calibration methods were applied to de-embed the impact of cryostat and optical elements on device under test measurements. The devices were measured through vacuum windows via focused beam radiation. A de-embedding method employing line-reflect-match (LRM) calibration was established to account for the effects of optical components and vacuum windows. Such a method does not require multiple line standards inside the cryostat and mechanical translation of quasioptics. System validation was performed with measurements of cryogenically cooled devices, such as bare silicon wafers and stainless-steel frequency-selective surface (FSS) bandpass filters, and superconducting bandpass FSS fabricated in niobium. A permittivity reduction of Si based on a 4 GHz resonance shift was observed concomitant with a drop in temperature from 296 to 4.8 K. The stainless steel FSS measurements revealed a relatively temperature invariant center frequency and return loss level of 263 GHz and 35 dB on average, respectively. Finally, a center frequency of 257 GHz was measured with the superconducting filters, with return loss improved by 11 dB on average at 4.8 K. To the best of our knowledge, this is the first reported attempt to scale LRM calibration to 330 GHz and use it to de-embed the impact of optics and cryostat from cryogenically cooled device S-parameters.
{"title":"Quasioptic, Calibrated, Full 2-Port Measurements of Cryogenic Devices Under Vacuum in the 220–330 GHz Band","authors":"Maxim Masyukov;Aleksi Tamminen;Irina Nefedova;Andrey Generalov;Samu-Ville Pälli;Roman Grigorev;Pouyan Rezapoor;Rui Silva;Juha Mallat;Juha Ala-Laurinaho;Zachary Taylor","doi":"10.1109/TTHZ.2025.3628558","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3628558","url":null,"abstract":"A quasi-optical (QO) test bench was designed, simulated, and calibrated for characterizing all four S-parameters of devices in the 220–330 GHz (WR3.4) frequency range, from room temperature down to 4.8 K. Quasioptical calibration methods were applied to de-embed the impact of cryostat and optical elements on device under test measurements. The devices were measured through vacuum windows via focused beam radiation. A de-embedding method employing line-reflect-match (LRM) calibration was established to account for the effects of optical components and vacuum windows. Such a method does not require multiple line standards inside the cryostat and mechanical translation of quasioptics. System validation was performed with measurements of cryogenically cooled devices, such as bare silicon wafers and stainless-steel frequency-selective surface (FSS) bandpass filters, and superconducting bandpass FSS fabricated in niobium. A permittivity reduction of Si based on a 4 GHz resonance shift was observed concomitant with a drop in temperature from 296 to 4.8 K. The stainless steel FSS measurements revealed a relatively temperature invariant center frequency and return loss level of 263 GHz and 35 dB on average, respectively. Finally, a center frequency of 257 GHz was measured with the superconducting filters, with return loss improved by 11 dB on average at 4.8 K. To the best of our knowledge, this is the first reported attempt to scale LRM calibration to 330 GHz and use it to de-embed the impact of optics and cryostat from cryogenically cooled device S-parameters.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"258-271"},"PeriodicalIF":3.9,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11224641","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-28DOI: 10.1109/TTHZ.2025.3626648
Dexian Yan;Leilei Xu;Shuai Sun;Yi Wang;Jia Li;Xiangjun Li;Le Zhang;Jining Li
Terahertz hollow core negative curvature fiber (HCNCF) offers high-performance waveguiding but face fabrication challenges due to complex processes. In this article, we present a simple and cost-effective new paradigm, the film-to-fiber method, utilizing commercial polyimide (PI) films to form a typical six-cladding-tube HCNCF structure. Additionally, metal microstructures can be integrated onto the PI film to enhance waveguiding properties. Three HCNCF types—without metal structures, with full metal integration, and with selective metal placement—are fabricated and characterized using terahertz time-domain spectroscopy system across 0.2–1.5 THz. Experimental results, including experimental loss, refractive index (birefringence), dispersion, and other parameters, align well with numerical simulations. This study introduces a cost-effective and flexible fabrication approach that accommodates polymer films of arbitrary thickness, providing a new paradigm for HCNCF manufacturing and advancing terahertz applications.
{"title":"A Novel Paradigm for Fabricating Terahertz Hollow-Core Negative Curvature Fibers","authors":"Dexian Yan;Leilei Xu;Shuai Sun;Yi Wang;Jia Li;Xiangjun Li;Le Zhang;Jining Li","doi":"10.1109/TTHZ.2025.3626648","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3626648","url":null,"abstract":"Terahertz hollow core negative curvature fiber (HCNCF) offers high-performance waveguiding but face fabrication challenges due to complex processes. In this article, we present a simple and cost-effective new paradigm, the film-to-fiber method, utilizing commercial polyimide (PI) films to form a typical six-cladding-tube HCNCF structure. Additionally, metal microstructures can be integrated onto the PI film to enhance waveguiding properties. Three HCNCF types—without metal structures, with full metal integration, and with selective metal placement—are fabricated and characterized using terahertz time-domain spectroscopy system across 0.2–1.5 THz. Experimental results, including experimental loss, refractive index (birefringence), dispersion, and other parameters, align well with numerical simulations. This study introduces a cost-effective and flexible fabrication approach that accommodates polymer films of arbitrary thickness, providing a new paradigm for HCNCF manufacturing and advancing terahertz applications.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"318-330"},"PeriodicalIF":3.9,"publicationDate":"2025-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The terahertz (THz) frequency range is considered an important spectrum for future six-generation communication. However, the high propagation losses and poor penetration inherent to THz waves restricted its development. Wavefront manipulation techniques for beam steering to redirect the propagation directions are essential for mitigating these limitations. In this article, cross-polarization conversion-based phase engineering for THz reflective beam steering is presented. This approach has the advantages of enabling quasi-linear phase response with sufficient phase-shifting range and maintaining high reflection magnitudes over a wide frequency band. Furthermore, a four-port equivalent circuit is developed to explain the design principle and verify the effectiveness of the polarizers. As a result, the metasurfaces composed of the proposed unit cells achieve stable wide-angle beam steering with high reflection intensity and have continuous frequency-scanning capability. In addition, the metasurfaces are verified to support the high-quality quadrature amplitude modulation with 16 states with an acceptable power penalty in a non-line-of-sight THz link.
{"title":"Wide-Angle Reflective Terahertz Beam Steering Metasurface Based on Cross-Polarization Conversion","authors":"Mengyao Li;Zhonghua Gu;Cheemalamarri Hemanth Kumar;Nanhan Liu;Frédéric Dutin;Pascal Szriftgiser;Guillaume Ducournau;Prakash Pitchappa","doi":"10.1109/TTHZ.2025.3626144","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3626144","url":null,"abstract":"The terahertz (THz) frequency range is considered an important spectrum for future six-generation communication. However, the high propagation losses and poor penetration inherent to THz waves restricted its development. Wavefront manipulation techniques for beam steering to redirect the propagation directions are essential for mitigating these limitations. In this article, cross-polarization conversion-based phase engineering for THz reflective beam steering is presented. This approach has the advantages of enabling quasi-linear phase response with sufficient phase-shifting range and maintaining high reflection magnitudes over a wide frequency band. Furthermore, a four-port equivalent circuit is developed to explain the design principle and verify the effectiveness of the polarizers. As a result, the metasurfaces composed of the proposed unit cells achieve stable wide-angle beam steering with high reflection intensity and have continuous frequency-scanning capability. In addition, the metasurfaces are verified to support the high-quality quadrature amplitude modulation with 16 states with an acceptable power penalty in a non-line-of-sight THz link.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"307-317"},"PeriodicalIF":3.9,"publicationDate":"2025-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-23DOI: 10.1109/TTHZ.2025.3624956
Myeongsang Shim;Chan-Gyu Choi;Sungmin Cho;Ho-Jin Song
This article presents a full D-band (110–170 GHz) frequency sixtupler MMIC and waveguide module for instrumentation applications. The frequency sixtupler, implemented in indium phosphide (InP) 250-nm double heterojunction bipolar transistor (DHBT) technology consists of a frequency tripler and a frequency doubler, both driven by amplifiers to provide sufficient power. The sixtupler operates across the full D-band by driving the multipliers with sufficient power for the saturated output power and using a doubly-tuned transformer for wideband frequency matching. The sixtupler MMIC is then packaged into a split-block waveguide module with an E-plane probe on a quartz substrate for a microstrip-to-waveguide transition. The transition coupler is designed to compensate for impedance mismatch caused by a bond-wire. Measured output power ranges from 2.7 to 9.8 dBm from the on-wafer test and –1.9 to 8.1 dBm from the waveguide module test, respectively, across the full D-band.
{"title":"Full D-Band InP Frequency Sixtupler MMIC and Waveguide Module for Instrumentation Application","authors":"Myeongsang Shim;Chan-Gyu Choi;Sungmin Cho;Ho-Jin Song","doi":"10.1109/TTHZ.2025.3624956","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3624956","url":null,"abstract":"This article presents a full D-band (110–170 GHz) frequency sixtupler MMIC and waveguide module for instrumentation applications. The frequency sixtupler, implemented in indium phosphide (InP) 250-nm double heterojunction bipolar transistor (DHBT) technology consists of a frequency tripler and a frequency doubler, both driven by amplifiers to provide sufficient power. The sixtupler operates across the full D-band by driving the multipliers with sufficient power for the saturated output power and using a doubly-tuned transformer for wideband frequency matching. The sixtupler MMIC is then packaged into a split-block waveguide module with an E-plane probe on a quartz substrate for a microstrip-to-waveguide transition. The transition coupler is designed to compensate for impedance mismatch caused by a bond-wire. Measured output power ranges from 2.7 to 9.8 dBm from the on-wafer test and –1.9 to 8.1 dBm from the waveguide module test, respectively, across the full D-band.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"347-351"},"PeriodicalIF":3.9,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A monolithic geodesic H-plane horn array antenna that operates up to 170 GHz is achieved for the first time using a low-cost additive manufacturing (AM) technique. To reach high gain and symmetric beam, a truncated geodesic H-plane horn is used to obtain a narrow beam in the H-plane, while a 1:8 power divider built on parallel-plate waveguides is constructed to narrow the beam in the E-plane. A ray-tracing and physical-optics model is developed to facilitate the design, which is capable of computing the full radiation pattern, directivity, and gain (considering conductive losses) of geodesic H-plane horn array antennas with significant time efficiency and high degree of accuracy. The adopted metal-only laser powder–bed fusion AM technique is especially suitable for fast prototyping structures with intricate shapes at a low cost. However, special adaptations are still considered in the design to ensure a successful fabrication of the prototype operating at the D-band. The prototype maintains good frequency stability from 110 to 170 GHz with a return loss better than 10 dB and a symmetric pencil beam. The measured data show a maximum realized gain of 29 dBi, a maximum aperture efficiency of 67% (calculated using realized gain), and a maximum radiation efficiency of 86%.
{"title":"A Sub-THz Low-Cost Additive Manufactured Monolithic Geodesic H-Plane Horn Array Antenna","authors":"Mingzheng Chen;José Rico-Fernández;Hairu Wang;Cleofás Segura-Gómez;Francisco Mesa;Oscar Quevedo-Teruel","doi":"10.1109/TTHZ.2025.3623926","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3623926","url":null,"abstract":"A monolithic geodesic H-plane horn array antenna that operates up to 170 GHz is achieved for the first time using a low-cost additive manufacturing (AM) technique. To reach high gain and symmetric beam, a truncated geodesic H-plane horn is used to obtain a narrow beam in the H-plane, while a 1:8 power divider built on parallel-plate waveguides is constructed to narrow the beam in the E-plane. A ray-tracing and physical-optics model is developed to facilitate the design, which is capable of computing the full radiation pattern, directivity, and gain (considering conductive losses) of geodesic H-plane horn array antennas with significant time efficiency and high degree of accuracy. The adopted metal-only laser powder–bed fusion AM technique is especially suitable for fast prototyping structures with intricate shapes at a low cost. However, special adaptations are still considered in the design to ensure a successful fabrication of the prototype operating at the <italic>D</i>-band. The prototype maintains good frequency stability from 110 to 170 GHz with a return loss better than 10 dB and a symmetric pencil beam. The measured data show a maximum realized gain of 29 dBi, a maximum aperture efficiency of 67% (calculated using <italic>realized gain</i>), and a maximum radiation efficiency of 86%.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"296-306"},"PeriodicalIF":3.9,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11208824","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Array detection chip is one of the key components of terahertz (THz) systems, with important applications in nondestructive testing, perspective imaging, and high-speed communication. This letter proposes an optical readout THz stacked metamaterial array chip operating at a frequency near the atmospheric window (0.22 THz). It adopts the design of upper and lower chips separation and then bonding to achieve the stacked structure. The upper chip combines with metamaterial cantilever pixels to achieve sensing and execution functions, while the lower chip undertakes auxiliary and support functions. The incident THz radiation can be absorbed and converted to mechanical energy of pixels, then read out in parallel at high speed by the optical system. The stacked mechanism reduces the size and thickness of the sensing/execution structure and improves the radiation–thermal–mechanical sensitivity of the chip. Spectral measurements show that its absorptivity is 97%. Meanwhile, the time measurement results indicate that the chip can quickly respond to THz radiation, with a response time of 1.62 ms.
{"title":"Optical Readout Terahertz Stacked Metamaterial Array Chip","authors":"Han Wang;Zhigang Wang;Cheng Gong;Bo Yan;Xinyu Li;Yayuan Zhang;Nan Zhang;Huali Zhu;Jierong Cheng;Fei Fan;Shengjiang Chang","doi":"10.1109/TTHZ.2025.3623783","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3623783","url":null,"abstract":"Array detection chip is one of the key components of terahertz (THz) systems, with important applications in nondestructive testing, perspective imaging, and high-speed communication. This letter proposes an optical readout THz stacked metamaterial array chip operating at a frequency near the atmospheric window (0.22 THz). It adopts the design of upper and lower chips separation and then bonding to achieve the stacked structure. The upper chip combines with metamaterial cantilever pixels to achieve sensing and execution functions, while the lower chip undertakes auxiliary and support functions. The incident THz radiation can be absorbed and converted to mechanical energy of pixels, then read out in parallel at high speed by the optical system. The stacked mechanism reduces the size and thickness of the sensing/execution structure and improves the radiation–thermal–mechanical sensitivity of the chip. Spectral measurements show that its absorptivity is 97%. Meanwhile, the time measurement results indicate that the chip can quickly respond to THz radiation, with a response time of 1.62 ms.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"342-346"},"PeriodicalIF":3.9,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article presents a two-way four-stage subterahertz (sub-THz) power amplifier (PA) fabricated in an advanced 130-nm SiGe BiCMOS process with $mathbf {f}_mathbf {T}$/$mathbf {f}_mathbf {{max}}$ = 470/650 GHz. To achieve compact and broadband performances simultaneously in a sub-THz band, a novel four-conductor subquarter-wavelength transmission line (T-line) balun is proposed. Compared to the conventional three-conductor balun, the proposed structure employs additional metal layers to form extra T-lines, achieving a wider impedance matching bandwidth. In addition, the vertical stacking layout reduces the overall size. Based on a generalized modeling analysis for asymmetric multilayer balun, the characteristics of the four-conductor balun are also analyzed in detail. The sub-THz PA using the proposed techniques exhibits a peak gain of 22 dB, a 3 dB small-signal bandwidth of 60 GHz (249–309 GHz) and a 3 dB saturated power bandwidth of 65 GHz (245–310 GHz). At 275 GHz, a maximum saturated power of 11.5 dBm was measured with a –1dB compressed output power ($ mathbf {OP_{-1dB}}$) of 10.5 dBm and a maximum power-added efficiency of 2.08%. The total core area is only 0.048 $mathbf {mm^{2}}$ with 306.25 $mathbf {mW/mm^{2}}$ output power per unit die area, which is the best performance among the reported PAs around 300 GHz.
{"title":"A Compact 249–309 GHz Power Amplifier Using a Four-Conductor Transmission Line Balun","authors":"Shouqing Fu;Shuyang Li;Huibo Wu;Xin Liu;Xingcun Li;Quanqin Liao;Shunhua Hu;Wenhua Chen","doi":"10.1109/TTHZ.2025.3623770","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3623770","url":null,"abstract":"This article presents a two-way four-stage subterahertz (sub-THz) power amplifier (PA) fabricated in an advanced 130-nm SiGe BiCMOS process with <inline-formula><tex-math>$mathbf {f}_mathbf {T}$</tex-math></inline-formula>/<inline-formula><tex-math>$mathbf {f}_mathbf {{max}}$</tex-math></inline-formula> = 470/650 GHz. To achieve compact and broadband performances simultaneously in a sub-THz band, a novel four-conductor subquarter-wavelength transmission line (T-line) balun is proposed. Compared to the conventional three-conductor balun, the proposed structure employs additional metal layers to form extra T-lines, achieving a wider impedance matching bandwidth. In addition, the vertical stacking layout reduces the overall size. Based on a generalized modeling analysis for asymmetric multilayer balun, the characteristics of the four-conductor balun are also analyzed in detail. The sub-THz PA using the proposed techniques exhibits a peak gain of 22 dB, a 3 dB small-signal bandwidth of 60 GHz (249–309 GHz) and a 3 dB saturated power bandwidth of 65 GHz (245–310 GHz). At 275 GHz, a maximum saturated power of 11.5 dBm was measured with a –1dB compressed output power (<inline-formula><tex-math>$ mathbf {OP_{-1dB}}$</tex-math></inline-formula>) of 10.5 dBm and a maximum power-added efficiency of 2.08%. The total core area is only 0.048 <inline-formula><tex-math>$mathbf {mm^{2}}$</tex-math></inline-formula> with 306.25 <inline-formula><tex-math>$mathbf {mW/mm^{2}}$</tex-math></inline-formula> output power per unit die area, which is the best performance among the reported PAs around 300 GHz.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"272-285"},"PeriodicalIF":3.9,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-13DOI: 10.1109/TTHZ.2025.3620905
Ryoma Sonoyama;Masahiko Inami;Yasuaki Monnai
Terahertz (THz) waves offer significant potential for advanced sensing and communication applications. However, severe path loss due to short wavelengths, as dictated by the Friis transmission formula, requires high-gain antennas to enhance signal levels in free space. The implementation of passive phased arrays for high-gain beam steering faces challenges in the THz range due to the lack of broadband and low-loss phase shifters. In addition, the steerable range of a phased array is usually limited. To circumvent these limitations, we propose a novel antenna design capable of omnidirectional steering of a THz fan beam in the WR3.4 band (220–330 GHz). This design hybridizes spatial and waveguide optics approaches and is based on a cylindrically symmetric structure that radiates a horizontally narrow and vertically wide fan beam in an arbitrary direction. The structure incorporates a tiny gimbal reflector that converts a TE11 mode from a circular waveguide into a guided wave in any azimuthal direction toward a narrowing taper, from which the wave is emitted into free space as a fan beam. Key design parameters, including waveguide dimensions and gimbal tilt, are optimized to balance beam collimation, fast steering, and device minimization. Experimental results validate the predicted radiation patterns and polarization, and demonstrate two types of beam scanning. Continuous beam steering is achieved in 5$^{circ }$ steps with a scan speed of 561 revolutions per minute. In addition, agile beam steering between two opposite azimuthal directions (180$^{circ }$ apart) is completed within ${text{12.9}} pm {text{3.1}}$ ms. This result lays the foundation for agile beam steering in THz communication systems, supporting real-time tracking of users and devices.
{"title":"Agile Omnidirectional Terahertz Fan-Beam Steering in the WR3.4 Band Based on Gimbal-Controlled Annular Aperture Excitation","authors":"Ryoma Sonoyama;Masahiko Inami;Yasuaki Monnai","doi":"10.1109/TTHZ.2025.3620905","DOIUrl":"https://doi.org/10.1109/TTHZ.2025.3620905","url":null,"abstract":"Terahertz (THz) waves offer significant potential for advanced sensing and communication applications. However, severe path loss due to short wavelengths, as dictated by the Friis transmission formula, requires high-gain antennas to enhance signal levels in free space. The implementation of passive phased arrays for high-gain beam steering faces challenges in the THz range due to the lack of broadband and low-loss phase shifters. In addition, the steerable range of a phased array is usually limited. To circumvent these limitations, we propose a novel antenna design capable of omnidirectional steering of a THz fan beam in the WR3.4 band (220–330 GHz). This design hybridizes spatial and waveguide optics approaches and is based on a cylindrically symmetric structure that radiates a horizontally narrow and vertically wide fan beam in an arbitrary direction. The structure incorporates a tiny gimbal reflector that converts a TE<sub>11</sub> mode from a circular waveguide into a guided wave in any azimuthal direction toward a narrowing taper, from which the wave is emitted into free space as a fan beam. Key design parameters, including waveguide dimensions and gimbal tilt, are optimized to balance beam collimation, fast steering, and device minimization. Experimental results validate the predicted radiation patterns and polarization, and demonstrate two types of beam scanning. Continuous beam steering is achieved in 5<inline-formula><tex-math>$^{circ }$</tex-math></inline-formula> steps with a scan speed of 561 revolutions per minute. In addition, agile beam steering between two opposite azimuthal directions (180<inline-formula><tex-math>$^{circ }$</tex-math></inline-formula> apart) is completed within <inline-formula><tex-math>${text{12.9}} pm {text{3.1}}$</tex-math></inline-formula> ms. This result lays the foundation for agile beam steering in THz communication systems, supporting real-time tracking of users and devices.","PeriodicalId":13258,"journal":{"name":"IEEE Transactions on Terahertz Science and Technology","volume":"16 3","pages":"286-295"},"PeriodicalIF":3.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146216613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：