{"title":"A CM-based fast computation method for the angular glint feature of multiple objects","authors":"Jihong Gu;Jiaxuan Wang;Jie Kang;Jiamin Shi;Zhaoyuan Wang;Dazhi Ding","doi":"10.1029/2025RS008245","DOIUrl":"https://doi.org/10.1029/2025RS008245","url":null,"abstract":"A novel method based on the theory of characteristic modes to fast extract the angular glint feature of multiple objects is proposed in this paper. The Characteristic Modes (CMs) of a single object are obtained with the EFIE-based CMs equation. The primary currents induced by the incident plane wave and the primary scattering fields are obtained through the linear superposition of each object's CMs. Considering the reconstructed primary currents as secondary sources, the coupling effect among objects can also be calculated using linear superposition. Finally, the reconstructed scattering field is utilized to calculate the angular glint linear deviation with the energy-flow tilt concept. The accuracy and efficiency of the proposed method are validated by several examples. The angular glint of unmanned aerial vehicle formations with varying spacings and attitudes is studied with the proposed method, providing a valuable reference for enhancing or suppressing the angular glint of multiple objects.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-15"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-06-01DOI: 10.1029/2024RS008094
Sangeetha Subbaraj;Saffrine Kingsly
{"title":"A review on ultra-wideband antennas for through wall imaging and ground penetrating radar applications","authors":"Sangeetha Subbaraj;Saffrine Kingsly","doi":"10.1029/2024RS008094","DOIUrl":"https://doi.org/10.1029/2024RS008094","url":null,"abstract":"This paper presents the review on the design of various ultra-wideband antennas through wall imaging in radar applications. The technical and methodological features in the design of ultra-wideband is examined in this work. The parameters such as gain, directivity, frequency bandwidth sidelobe level and complexity involved in the design are studied. Furthermore, the image resolution and penetration depth required for Ground Penetrating Radar systems depends on the antenna parameters are analyzed in detail. The proposed manuscript gives a depth study of the suitable antenna design for penetrating ground radars. The comparative study is made on the various types of UWB antenna with a focus (a) To highlight the requirement for UWB antennas in wall imaging radar imaging systems (b) To describe the techniques used to enhance the performance of the antenna.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-15"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An omnidirectional low-profile dual-polarized UWB antenna for dual-functional applications in Internet of vehicles","authors":"Yuanqing Zhu;Xiaoming Liu;Shuo Yu;Aiqing Zhang;Youhong Feng;Xiaojun Jing","doi":"10.1029/2025RS008263","DOIUrl":"https://doi.org/10.1029/2025RS008263","url":null,"abstract":"In this paper, a snowflake-shaped low-profile ultra-wideband (UWB) antenna is reported for dual function multiplexing of the Passive Keyless Entry and Start (PKES) system and the Automated Valet Parking (AVP) system. This antenna demonstrates preferred properties of omnidirectional radiation patterns and dual polarization. Both horizontally polarized (HP) and vertically polarized (VP) elements cover the UWB band, ensuing reliable signal receiving/transmitting. The omnidirectional radiation patterns are obtained over the whole working frequency band, which is much preferred in uses of PKES and AVP. To realize omnidirectional patterns, the HP antenna comprises eight dual-antipodal Vivaldi antennas arranged in a circular array, connected by a 1-to-8 power divider. Corrugated edges and shorting pins are introduced to improve bandwidth. Meanwhile, the VP antenna is formed by two cross low-profile tapered monopolies, which also provide omnidirectional radiation over the whole UWB range. The proposed antenna boasts a compact size of only 96 × 96 × 7 mm, with a height of 0.07λ<inf>min</inf> (λ<inf>min</inf> represents the free-space wavelength at the minimum operating frequency). The realized bandwidth covers 3.06–10.62 GHz, which encompasses the UWB band and V2X band. The measured gain variation in different directions is less than 3 dB, confirming satisfactory omnidirectional radiation. Specifically, in the V2X band, the isolation is better than 25 dB. These advantageous properties render the antenna an ideal candidate for UWB applications of PKES and AVP in IoV.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-13"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A novel single DVCCTA based electronically tunable, wideband, four-mode instrumentation amplifier","authors":"Harika Pamu;Puli Kishore Kumar;Kiran Kumar Gurrala","doi":"10.1029/2025RS008241","DOIUrl":"https://doi.org/10.1029/2025RS008241","url":null,"abstract":"This paper describes a new instrumentation amplifier (IA) that has the ability to operate in all four possible modes: voltage, current, transimpedance, and transadmittance mode using a single Differential Voltage Current Conveyor Transconductance Amplifier (DVCCTA) along with external grounded resistors. The suggested IA structures offer a broad range of common mode rejection ratio bandwidth (BW) and differential gain (A<inf>dm</inf>) bandwidth of around (18.7 MHz, 26 MHz) for voltage mode, (17.29 MHz, 1.05 GHz) for current mode, (25.25 MHz, 168 MHz) for transimpedance mode and (17.29 MHz, 1.05 GHz) for transadmittance mode respectively, in which an unreported finding of 1.05 GHz gain BW underscores the uniqueness of the designs. Additionally, they are suitable for IC integration due to the available grounded passive attributes. Moreover, the designs come with an interesting feature for electronically tuning the gains via biasing current (I<inf>B</inf>) and also have a low power dissipation. Realization of DVCCTA uses 20MOS transistors, and OrCAD PSPICE with a 0.18 μm TSMC CMOS technology parameter is used to authenticate the workableness of the proposed IA circuits. The performance of the suggested topologies is analyzed by considering the non-idealities of the DVCCTA. Apart from that, process, voltage, temperature-dependent variations and Monte Carlo simulations are also delineated for the verification of the proposed designs. The functionality of the circuits has also been validated through practical experimentation, employing commercially accessible current feedback operational amplifiers, such as the ICAD844 and post layout simulations. The simulation results correlate well with the theoretical prediction.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-32"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-06-01DOI: 10.1029/2024RS008081
S. Sokolovskiy;I. Zakharenkova;D. C. Hunt;J. J. Braun;J. P. Weiss;W. S. Schreiner;Iu. Cherniak;Q. Wu;T. Vanhove
{"title":"Geolocation of the ionospheric irregularities in the equatorial F layer by back propagation of COSMIC-2 radio occultation signals","authors":"S. Sokolovskiy;I. Zakharenkova;D. C. Hunt;J. J. Braun;J. P. Weiss;W. S. Schreiner;Iu. Cherniak;Q. Wu;T. Vanhove","doi":"10.1029/2024RS008081","DOIUrl":"https://doi.org/10.1029/2024RS008081","url":null,"abstract":"Plasma irregularities in the ionosphere induce scintillation of radio signals. Radio occultation (RO) observations of the Global Navigation Satellite Systems (GNSS) signals from low Earth orbit (LEO) allow monitoring of the ionospheric scintillation. Under certain conditions, it is possible to localize (geolocate) plasma irregularities along the line-of-sight between the GNSS and LEO satellites. While several techniques have been considered for the localization, in this study we use the back propagation (BP) of complex RO signals (phase and amplitude) measured at a high rate (HR), 50–100 Hz. Our method is based on a numerical solution of the wave equation, originally proposed for geolocation in 2002, with some modifications. We consider theoretical aspects of the BP technique, including assumptions, approximations and limitations, and perform numerical modeling of radio wave propagation. We investigate geolocation by BP for two regions with aligned and mis-aligned irregularities and explain multi-valued geolocations. We focus on the equatorial F region, consistent with the COSMIC-2 observation sampling and use the IGRF-13 model of the Earth's magnetic field to define the orientation of plasma irregularities. We use our method for processing of COSMIC-2 HR scintillation data collected from the precise orbit determination antennas for 2 years: 2021 and 2023 (years with low and high solar activity). The results, represented by gridded monthly maps of geolocations, show clear seasonal and interannual variations. Additionally, we present comparison of the geolocations obtained independently from L1 and L2 signals for a 2-month period.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-21"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Manually reconfigurable reflecting surface (MRRS) by detached rotatable unit cells for 5G FR2 radio coverage at low-cost fabrication","authors":"H.-T. Chou;D.-Y. Lin;N.-W. Chen;S. Kawdungta;D. Torrungrueng","doi":"10.1029/2025RS008306","DOIUrl":"https://doi.org/10.1029/2025RS008306","url":null,"abstract":"A manually reconfigurable reflecting surface (MRRS) formed by detached rotatable unit cells is proposed to enhance the signal strengths in 5G FR2 radio coverage. The forming unit cell is a conductor-backed circular-patch-based element implemented with two anti-symmetric arms manually extendable to adjust the relative reflection phases. The proposed MRRS is structured in a two-substrate configuration on a ground plane. The first dielectric substrate accommodates all identical and detachable elements manually rotated to reconfigure the MRRS's reflection phases. In contrast, the second substrate's top face imprints the two arms' footprints. The reflection phases are altered by adjusting the overlapped arms' lengths between the two dielectric substrates. This allows one to redirect and reconfigure the scattering fields' patterns in the desired coverage area. Based on the novel configuration of unit cells, the cross-polarization of the reflected waves can be significantly reduced with the interleaved and mirrored cell constellation. A 21 × 21-element MRRS in the format of reflectarray is designed at 28 GHz to validate the effectiveness through experimental measurements. The measured results show 4% 1 dB and 7% 3 dB gain bandwidths. The maximum gain at 28 GHz is 25.6 dB, and the aperture efficiency is approximately 37.8%.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-13"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-06-01DOI: 10.1029/2024RS008165
Sami Abduljabbar Rashid;Lukman Audah;Mustafa Maad Hamdi;Mohammed Salah Abood;Ghassan Raad Abbas;Bassim Sayed Mohammed;Taha A. Elwi;Salahuddin Khan;Bal S. Virdee;Astrit Krasniqi;Lida Kouhalvandi;Mohammad Alibakhshikenari
{"title":"Delay-minimization and back-off aware Q-learning with advanced bio-inspired CH selection for multi-hop communication in vehicular ad-hoc networks","authors":"Sami Abduljabbar Rashid;Lukman Audah;Mustafa Maad Hamdi;Mohammed Salah Abood;Ghassan Raad Abbas;Bassim Sayed Mohammed;Taha A. Elwi;Salahuddin Khan;Bal S. Virdee;Astrit Krasniqi;Lida Kouhalvandi;Mohammad Alibakhshikenari","doi":"10.1029/2024RS008165","DOIUrl":"https://doi.org/10.1029/2024RS008165","url":null,"abstract":"The increasing significance of Vehicular Ad-hoc Networks (VANETs) in intelligent transportation systems has introduced challenges related to high mobility, network congestion, and energy efficiency. To address these challenges, this paper proposes a new approach based on Delay-Minimization and Back-Off Aware Q-Learning with Advanced Bio-Inspired Cluster Head (CH) Selection (DBACH) to enhance multi-hop data transmission in VANETs. The DBACH framework features network formation, latency minimization, a back-off Q-learning model, and an improved dragonfly algorithm-based CH selection. This method reduces transmission delay, routing overhead, and power consumption to enhance VANET QoS. DBACH was evaluated against RCDC, DCPA, and WCAM for effectiveness. The simulated vehicle numbers and speeds (km/h) were used to assess energy efficiency, throughput, packet delivery ratio, data loss ratio, computation time, and routing overhead. The DBACH boosts energy efficiency to 85 J, throughput to 160–200 Kbps, and packet delivery ratio to 11%—13%. Data loss drops to 7%–15%, latency is 60–94 ms, and routing overhead is 170—300 packets. When DBACH is a promising option for enhancing VANET communication dependability and energy economy due to its efficiency, communication stability, and success rates.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 6","pages":"1-17"},"PeriodicalIF":1.6,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144550378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-04-01DOI: 10.1029/2024RS008142
Ahmet Uluslu;Kervendurdy Allaberdiyev
{"title":"Competitive metaheuristic algorithms for building a performance database of a dual-band combline bandpass filter with microstrip connection","authors":"Ahmet Uluslu;Kervendurdy Allaberdiyev","doi":"10.1029/2024RS008142","DOIUrl":"https://doi.org/10.1029/2024RS008142","url":null,"abstract":"Dual-band bandpass filters have attracted intense attention in recent developments to meet many demands, especially wireless applications and multi-band radio wave. Here, a Combline filter in the form of a dual bandpass 3-row microstrip with a center resonance frequency of 2.5 and 3.0 GHz and a total of 13 design parameters, 6 of which are variable, has become a single-objective and multi-dimensional optimization design problem with the help of current competitive metaheuristic algorithms. Algorithms have been derived in recent years, have proven their success against existing algorithms, and have not been used in the filter design problem. In addition, in a different study conducted in recent years, among five different objective function pairs that were fabricated from mathematical models that have proven successful, the three most successful objective function pairs were selected based on the relevant study results and these objective function pairs were adapted for the filter and included in the study. Throughout this design optimization process, the filter toolbox in the R2023B version, available as of the MATLAB R2022B version, was used. In addition to the original objective function, the study includes multiple innovations such as the new filter toolbox and current competitive metaheuristic algorithms. During this entire optimization process, the most optimal results are verified by electromagnetic simulation. Considering all these results in the study, the optimization processes performed with the proposed competitive algorithms are an easy, fast and efficient solution for complex and multi-dimensional filter design optimization applications. Additionally, it can be quickly applied to other microwave optimization problems by changing the objective functions.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 4","pages":"1-18"},"PeriodicalIF":1.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143908345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-04-01DOI: 10.1029/2025RS008270
Kazuya Kobayashi;Jothiram Vivekanandan
{"title":"Thank you to our 2024 reviewers","authors":"Kazuya Kobayashi;Jothiram Vivekanandan","doi":"10.1029/2025RS008270","DOIUrl":"https://doi.org/10.1029/2025RS008270","url":null,"abstract":"The Editors thank the 2024 peer reviewers. As you are aware, the journal Radio Science (RDS) publishes original research papers on electromagnetic propagation and its applications. In 2024, we received a total of 206 manuscripts for consideration for publication in the RDS. We tried very carefully to find reviewers who were best fit to the topics of manuscripts. You worked hard in the peer-review process and gave us excellent evaluations. Our journal would never have kept a high reputation without your continued efforts. Thank you all for your significant contributions to the review process and we look forward to working with you also this year and in the coming years.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 4","pages":"1-4"},"PeriodicalIF":1.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143908348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Radio SciencePub Date : 2025-04-01DOI: 10.1029/2024RS008157
P. Chowdhury;E. Spencer;P. Adhya;S. Patra;S. K. Vadepu;P. S. Rayapati
{"title":"Analysis of sweeping impedance probe measurements in the F-layer of the ionosphere during the occurrence of a mid-latitude spread F event","authors":"P. Chowdhury;E. Spencer;P. Adhya;S. Patra;S. K. Vadepu;P. S. Rayapati","doi":"10.1029/2024RS008157","DOIUrl":"https://doi.org/10.1029/2024RS008157","url":null,"abstract":"Plasma Impedance Probes (PIP) are AC instruments that are used to measure and observe resonances and damping features in plasmas. These probes are typically flown on sounding rocket missions studying ionosphere plasma physics. In this work we present a combined circuit—empirical model for the frequency dependent impedance of a monopole probe on a sounding rocket payload that traverses multiple ionospheric layers. The purpose of this model is to resolve some difficulties encountered when interpreting and analyzing PIP measurements made at the higher altitudes during the Tropical STORMS sounding rocket launched from Wallops Island, Virginia, in 2007. In an earlier work (Spencer & Patra, 2015, https://doi.org/10.1002/2015rs005697), we identified the presence of anomalous damping in the measurements above 260 km. Here, we introduce a more detailed model of the plasma probe interaction to explain these observations. The new model incorporates the effect of a sheath, and some additional parallel conductivity elements that dampen the observed impedance in the F-layer of the ionosphere. We show that by accounting for the presence and gradual impact of the parallel conductance elements, the PIP data can be accurately analyzed and interpreted. We hypothesize that secondary electrons with higher mobilities may contribute to the observed effects, and propose future investigations that may be conducted to further understand the observations.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 4","pages":"1-19"},"PeriodicalIF":1.6,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143908279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}