Radio Science最新文献_第2页

A low ionosphere occultation observation method based on differential weight separation 基于差重分离的低电离层掩星观测方法

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008152

Jialiang Zhong;Sijia Han;Caiyun Wang;Wei Guo

引用次数: 0

Monitoring global ionospheric conditions with electromagnetic lightning impulses registered in extremely low frequency measurements 用极低频测量记录的电磁闪电脉冲监测全球电离层状况

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008140

Z. Nieckarz;M. Golkowski;J. Kubisz;M. Ostrowski;A. Michalec;J. Mlynarczyk;J. Lichtenberger;A. Maxworth

{"title":"Monitoring global ionospheric conditions with electromagnetic lightning impulses registered in extremely low frequency measurements","authors":"Z. Nieckarz;M. Golkowski;J. Kubisz;M. Ostrowski;A. Michalec;J. Mlynarczyk;J. Lichtenberger;A. Maxworth","doi":"10.1029/2024RS008140","DOIUrl":"https://doi.org/10.1029/2024RS008140","url":null,"abstract":"The Extremely Low Frequency band (ELF: 0.03-1,000 Hz) electromagnetic signals from thunderstorm lightning discharges can propagate around the globe in the Earth-ionosphere resonance cavity and thus be used for ionosphere monitoring. We use ELF observations of impulses detected by the World Wide Lightning Location Network (WWLLN) to investigate ELF propagation velocity and arrival azimuth under diurnal changes over 2 days in September 2023. Also, temporary effects of solar flares' ionizing fluxes are monitored, leading to increase of the ELF signal propagation speed in proportion to the X-ray flux intensity. We present a simple method for automatic and large-scale analysis, utilizing data from two registration systems (our ELF reciever and WWLLN) and enabling easy evaluation of changes in wave propagation speed. Comparative analysis of WWLLN identified impulses generated in Africa and America reveals varying effects of signal refraction, with increased azimuth changes for signals propagating across the ionospheric ionization gradients associated with the day/night terminator. The method has a potential to become a standard tool for the analysis and monitoring of the lower layers of the ionosphere.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 2","pages":"1-9"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535533","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}

引用次数: 0

Burj Khalifa-inspired reconfigurable microstrip patch antenna for wireless solutions 受哈利法塔启发的可重构微带贴片天线，用于无线解决方案

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008114

J. Salah;M. Madi;M. El Abbasi;M. Moussa;A. Daher;M. Hussein;K. Kabalan

{"title":"Burj Khalifa-inspired reconfigurable microstrip patch antenna for wireless solutions","authors":"J. Salah;M. Madi;M. El Abbasi;M. Moussa;A. Daher;M. Hussein;K. Kabalan","doi":"10.1029/2024RS008114","DOIUrl":"https://doi.org/10.1029/2024RS008114","url":null,"abstract":"This paper presents a new microstrip patch antenna inspired by the iconic Burj Khalifa, Dubai's world's tallest skyscraper. The antenna design focuses on being compact, lightweight, cost-effective, and versatile. Simulated through HFSS software, the patch antenna demonstrates a multi-frequency operation. Fabricated on a double-sided copper FR4 epoxy PCB (4 × 8 cm2, 1.6 mm thickness) using a coaxial probe feeding method, it achieves a gain exceeding 7 dB at 7 GHz. Prototypes show excellent consistency between measured and simulated reflection coefficients and gains at 4.8, 5.7, and 7 GHz. Two additional designs are presented to adjust the resonance frequency, making it suitable for biomedical sensors, WIFI, and point-to-point microwave links. One design involves adding a short slot that is close to the feed point, while the other design includes a pair of varactors. Both designs create a reconfigurable microstrip antenna with electromagnetic characteristics that can be adjusted to increase its electrical length. The antenna resonates at 4.8 GHz. The slotted short patch shifts the resonance to 3.1 GHz, and the varactor patch shifts the resonance frequency to 2.1 GHz. When the DC reverse bias voltage of the varactors varies from 0 to 6 V, the gain improves to 15.2 dB.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 2","pages":"1-15"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535449","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}

引用次数: 0

Compact and wideband cavity-backed antenna with elliptical coupling slot and elliptical aperture for satellite communications transceiver applications 具有椭圆耦合槽和椭圆孔径的小型宽带空腔背天线，用于卫星通信收发器

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008120

Y. Asci;C. Turkmen;M. Secmen

{"title":"Compact and wideband cavity-backed antenna with elliptical coupling slot and elliptical aperture for satellite communications transceiver applications","authors":"Y. Asci;C. Turkmen;M. Secmen","doi":"10.1029/2024RS008120","DOIUrl":"https://doi.org/10.1029/2024RS008120","url":null,"abstract":"A wideband full-metal cavity-backed antenna with elliptical coupling slot and elliptical aperture is proposed. The antenna consists of two elliptical structures, a coupling slot and a radiating aperture, which are placed on the feed waveguide side and the load side of a rectangular metal cavity resonator, respectively. By using an elliptical slot/aperture, the impedance bandwidth and gain of the antenna are found to be considerably improved in the same footprint and without increasing complexity compared to rectangular slot/aperture and also circular aperture. A prototype of the proposed wideband antenna is fabricated by using the additive manufacturing techniques of 3D printing with polylactic acid (PLA) material, which is covered with aluminum tape to validate the design at Ku-band for satellite communication (SatCom). The measured results show that the antenna has an impedance bandwidth of 4 GHz (10.86–14.86 GHz for |S<inf>11</inf>| < —15 dB), which gives a fractional bandwidth (FBW) of 31.1%. With low cross-polarization being less than — 25 dB at broadside, the antenna has a peak gain of 9 dBi. The proposed antenna is also compact, with a total volume of about 1.1λ<inf>0</inf>3 at the center frequency.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 2","pages":"1-13"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535440","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}

引用次数: 0

Design and optimization of a low-cost 5-m radio telescope at princess Nourah university (PNU), Saudi Arabia 沙特阿拉伯诺拉公主大学（PNU）低成本5米射电望远镜的设计与优化

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008170

Yazan M. Allawi;Eman M. Moneer;Modar Shbat;Walid M. Dyab;Mosab J. Banisalman;Norah M. Alwadai

{"title":"Design and optimization of a low-cost 5-m radio telescope at princess Nourah university (PNU), Saudi Arabia","authors":"Yazan M. Allawi;Eman M. Moneer;Modar Shbat;Walid M. Dyab;Mosab J. Banisalman;Norah M. Alwadai","doi":"10.1029/2024RS008170","DOIUrl":"https://doi.org/10.1029/2024RS008170","url":null,"abstract":"This paper presents the design and optimization of a low-cost, 5-m radio telescope developed at Princess Nourah University (PNU), focusing on the 1,420 MHz spectral line of neutral hydrogen (HI) for studying the structure and dynamics of the Milky Way galaxy. The design process integrates key principles of radio telescope engineering, including the optimization of the parabolic dish's geometry, reflectivity, and feed horn design and positioning. Key design outcomes include achieving a sensitivity of 19.63 m2 and an angular resolution of 2.94° providing our telescope with the ability to detect faint cosmic signals. Additionally, the focal length was optimized at 1.75 m with conical feed horn of circular aperture radius of 81.7 mm providing a directivity of 6.47 dB and an aperture efficiency of 51% achieving semi-optimal illumination for the designed reflector to minimize the signal loss. The resulting telescope gain of approximately 35 dB supports clear signal capture within the required frequency range. These performance metrics were verified through both simulations and experimental observations, confirming the high performance of our proposed radio telescope design. The advantages of this design include its affordability, replicability, and suitability for educational and research purposes, making it an accessible tool for radio astronomy studies in developing regions. The proposed radio telescope offers a cost-effective solution for institutions seeking to engage in astronomical research and develop hands-on learning experiences in antenna design and signal processing.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 2","pages":"1-17"},"PeriodicalIF":1.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535509","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}

引用次数: 0

Comparative analysis of performance for optimization-based transionospheric SAR autofocus 基于优化的过渡层SAR自动对焦性能比较分析

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008168

Mikhail Gilman;Semyon Tsynkov

引用次数: 0

Retraction: A survey of five generations of MIMO multiband base station antennas 摘要：五代MIMO多波段基站天线的研究

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/rds.21394

引用次数: 0

Characterization of the effective conductivity in radio frequency of additive manufacturing materials 增材制造材料射频有效导电性的表征

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-02-01 DOI: 10.1029/2024RS008149

Carmen Bachiller;Alvaro Ferrer;Aleksandr Voronov;Murta Capella;Francisco Boscá;M. Luisa Marin;Lluc Sempere;Mirko Kunowsky;Asunción Martínez-García

引用次数: 0

Application of SuperDARN interferometry for improved estimates of Doppler velocity and echo geolocation superdam干涉测量在改进多普勒速度估计和回波定位中的应用

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-01-01 DOI: 10.1029/2024RS008084

P. Ponomarenko;M. Ghalamkarian Nejad;A. V. Koustov

{"title":"Application of SuperDARN interferometry for improved estimates of Doppler velocity and echo geolocation","authors":"P. Ponomarenko;M. Ghalamkarian Nejad;A. V. Koustov","doi":"10.1029/2024RS008084","DOIUrl":"https://doi.org/10.1029/2024RS008084","url":null,"abstract":"It has been previously established that the Doppler velocities of F-region ionospheric echoes observed by the Super Dual Auroral Radar Network (SuperDARN) at high frequencies (HF, 8–20 MHz) are persistently lower than those measured by other instruments at the same locations. This was attributed to the ionospheric refractive index for HF radio waves being noticeably smaller than one. The refractive index values can be obtained in two ways: based on electron density estimates from a co-located instrument or a model, or by deriving them from SuperDARN elevation angle data. To compare these methods, we considered line-of-sight Doppler velocity observations by the Rankin Inlet (RKN) SuperDARN radar and the Resolute Bay Incoherent Scatter Radars (RISR). The velocity data were supplemented by electron density measurements from RISR. The elevation angle data were also used for accurate determination of SuperDARN echo geolocation because the actual ground range to the echo location may significantly differ from that obtained with the conventional SuperDARN models. The RISR Doppler velocity values were used as a reference to the RKN observations via 0.5-hop and 1.5-hop propagation paths. Correction by the index of refraction based on both maximum electron density from the RISR and elevation angle data from RKN brought 0.5-hop data close to the RISR velocity values, with the latter representing a self-contained approach. However, for 1.5-hop echoes from the polar cap, the uncorrected SuperDARN velocities exceeded those from RISR. We discuss potential causes of this apparent anomaly.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 1","pages":"1-15"},"PeriodicalIF":1.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106325","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}

引用次数: 0

Examining the power law relationship between absorption and frequency using spectral riometer data 利用光谱里程计的数据检验吸收和频率之间的幂律关系

IF 1.6 4区地球科学

Radio Science Pub Date : 2025-01-01 DOI: 10.1029/2024RS007951

R. A. D. Fiori;A. Kero;R. Gillies;T. G. Cameron;C. Cully;R. Ghaffari

{"title":"Examining the power law relationship between absorption and frequency using spectral riometer data","authors":"R. A. D. Fiori;A. Kero;R. Gillies;T. G. Cameron;C. Cully;R. Ghaffari","doi":"10.1029/2024RS007951","DOIUrl":"https://doi.org/10.1029/2024RS007951","url":null,"abstract":"High frequency radio wave propagation is sensitive to absorption in the D and lower E-region ionosphere. Absorption models typically characterize attenuation expected at 30 MHz, meaning scaling relationships are required to map to absorption expected at other frequencies. This is important when evaluating absorption at <20 MHz, as these frequencies are typically used for communication, and are highly sensitive to ionospheric disturbances. Typically, a power law relationship between absorption and frequency with a coefficient of n = − 2 is used. This relationship can be demonstrated through consideration of the Appleton-Hartree equation. This paper examines the performance of this relationship using data from the Kilpisjärvi Atmospheric Imaging Receiver Array for 13–14 November 2012. Using absorption measured at 30 MHz as a baseline, the power law relationship was used to calculated absorption at frequencies of 10–80 MHz. For this event, the power law relationship performed well when the measured absorption at 30 MHz was <1–2 dB, but strongly overestimated measurements as absorption increased. Performance improved when n was allowed to vary as a function of the overall level of absorption at 30 MHz. This accounts for local ionospheric changes associated with absorption events that change the balance of parameters in the Appleton-Hartree equation causing deviation from n = − 2. To further accommodate deviations associated with both local ionospheric disturbances and ambient electromagnetic noise contributions, an empirical relationship relating the logarithm of absorption to frequency was evaluated as a function of overall absorption. Compared to the simplified n = − 2 power law relationship between absorption and frequency, the new relationship better represents measured absorption for the event studied.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":"60 1","pages":"1-14"},"PeriodicalIF":1.6,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143106330","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}

引用次数: 0