IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)最新文献
We present a finite elements algorithm (FEA) for study of the global current systems produced by extra low frequency electromagnetic disturbances like hydromagnetic waves, solar-quite daily variations, and so on. All these problems can be reduced to Laplace's equation on a thin nonhomogeneous anisotropic shell. Our approach is based on satisfying this law within each elementary cell of the numerical grid. The main strength of the proposed algorithm is in the widely used finite difference method (FDM). It was found that the FDM accumulates numerical errors caused by numerical 'diffusion'. This artificial diffusion is a sequence of the finite difference representation of the differential operators of the original Laplace equation in a nonhomogeneous case.
{"title":"On the self-consistent algorithm for numerical simulation of the global geomagnetic disturbances and associated electric current spreading to low latitudes","authors":"L. Alperorich, B. Fidel","doi":"10.1109/APS.2001.960048","DOIUrl":"https://doi.org/10.1109/APS.2001.960048","url":null,"abstract":"We present a finite elements algorithm (FEA) for study of the global current systems produced by extra low frequency electromagnetic disturbances like hydromagnetic waves, solar-quite daily variations, and so on. All these problems can be reduced to Laplace's equation on a thin nonhomogeneous anisotropic shell. Our approach is based on satisfying this law within each elementary cell of the numerical grid. The main strength of the proposed algorithm is in the widely used finite difference method (FDM). It was found that the FDM accumulates numerical errors caused by numerical 'diffusion'. This artificial diffusion is a sequence of the finite difference representation of the differential operators of the original Laplace equation in a nonhomogeneous case.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128542764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A fast algorithm based on the volume integral equation is described for the analysis of antenna-radome interaction problems. The algorithm is implemented for both tetrahedron and hexahedron meshes, and is applicable to model arbitrarily shaped 3D dielectric radomes. The application of the multilevel fast multipole algorithm (MLFMA) significantly reduces the memory and CPU time requirement for solving the volume integral equation, and hence the algorithm presented in this paper can be applied to problems with electrically large sized radome. This algorithm is different from the ray tracing methods in that it yields highly accurate solution for radomes that contain small-scale geometric variations such as the sharp portion of the ogive radomes.
{"title":"Dielectric radome analysis using multilevel fast multiple algorithm","authors":"Caicheng Lu","doi":"10.1109/APS.2001.959569","DOIUrl":"https://doi.org/10.1109/APS.2001.959569","url":null,"abstract":"A fast algorithm based on the volume integral equation is described for the analysis of antenna-radome interaction problems. The algorithm is implemented for both tetrahedron and hexahedron meshes, and is applicable to model arbitrarily shaped 3D dielectric radomes. The application of the multilevel fast multipole algorithm (MLFMA) significantly reduces the memory and CPU time requirement for solving the volume integral equation, and hence the algorithm presented in this paper can be applied to problems with electrically large sized radome. This algorithm is different from the ray tracing methods in that it yields highly accurate solution for radomes that contain small-scale geometric variations such as the sharp portion of the ogive radomes.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128546428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A rectangular parallel-plate slot array fed by a post-wall waveguide is an attractive candidate for high-efficiency and mass-producible planar antennas in millimeterwave applications. The transmission loss is small in the waveguide in comparison with microstrip-type feed lines and the fabrication cost of simple via-holing and etching is low. The design is conducted assuming plane wave propagation, neglecting both the boundary conditions at the narrow walls and the slot coupling perturbation; this is effective only for an extremely large aperture and weakly coupled slots. Since the EM analysis for the actual structure seems too heavy, the key for the advanced design of the parallel plate waveguide arrays is to establish accurate, but still simple models, for the analysis and design. This paper discusses the fast evaluation of slot scattering inside the parallel plate waveguide. It gives the basis for future approximate but accurate analysis/design methods for parallel plate slotted waveguide arrays.
{"title":"Analysis of the internal scattering field distribution in an oversized rectangular slotted waveguide","authors":"H. Kai, J. Hirokawa, M. Ando","doi":"10.1109/APS.2001.959698","DOIUrl":"https://doi.org/10.1109/APS.2001.959698","url":null,"abstract":"A rectangular parallel-plate slot array fed by a post-wall waveguide is an attractive candidate for high-efficiency and mass-producible planar antennas in millimeterwave applications. The transmission loss is small in the waveguide in comparison with microstrip-type feed lines and the fabrication cost of simple via-holing and etching is low. The design is conducted assuming plane wave propagation, neglecting both the boundary conditions at the narrow walls and the slot coupling perturbation; this is effective only for an extremely large aperture and weakly coupled slots. Since the EM analysis for the actual structure seems too heavy, the key for the advanced design of the parallel plate waveguide arrays is to establish accurate, but still simple models, for the analysis and design. This paper discusses the fast evaluation of slot scattering inside the parallel plate waveguide. It gives the basis for future approximate but accurate analysis/design methods for parallel plate slotted waveguide arrays.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128181714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Excitation of the circularly polarized (CP) aperture-coupled hemispherical dielectric resonator antenna (DRA) using a parasitic patch is studied. The analysis consists of two parts, namely the DRA with a parasitic patch and the microstrip feed line. In this paper, theoretical results on the return loss and radiation field pattern are presented.
{"title":"Excitation of CP aperture-coupled dielectric resonator antenna with a parasitic patch","authors":"H. Ng, K. Leung","doi":"10.1109/APS.2001.959433","DOIUrl":"https://doi.org/10.1109/APS.2001.959433","url":null,"abstract":"Excitation of the circularly polarized (CP) aperture-coupled hemispherical dielectric resonator antenna (DRA) using a parasitic patch is studied. The analysis consists of two parts, namely the DRA with a parasitic patch and the microstrip feed line. In this paper, theoretical results on the return loss and radiation field pattern are presented.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128182995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present work is the continuation of previous investigations performed by the authors (1999) of electromagnetic short pulse propagation in different media. The following two adjustments are discussed: 1) The reflection and propagation of a short pulse in the half-space is considered instead of its propagation in infinite space as discussed in previous works; 2) The representation of the incident pulse field with Laguerre polynomials. It represents well the shape of a real pulse.
{"title":"Reflection and propagation of short electromagnetic pulse in plasma half-space and semi-infinite waveguide","authors":"A. Gutman","doi":"10.1109/APS.2001.958923","DOIUrl":"https://doi.org/10.1109/APS.2001.958923","url":null,"abstract":"The present work is the continuation of previous investigations performed by the authors (1999) of electromagnetic short pulse propagation in different media. The following two adjustments are discussed: 1) The reflection and propagation of a short pulse in the half-space is considered instead of its propagation in infinite space as discussed in previous works; 2) The representation of the incident pulse field with Laguerre polynomials. It represents well the shape of a real pulse.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128197139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the most desired innovations in modern antenna technology should be the widespread use of conformal designs. Antennas of this kind are expected to be applied primarily in arrays. However, another prospective application for conformal antennas is in handsets or other miniature terminals of mobile and wireless communications systems. The form of the handset and the range of available functions are the prerequisites of the phone market success. Furthermore, the terminal form is strongly related to a possibly large color display, which is no longer a tiny part of the device. Modern multimedia handsets call for multiband antennas, which should feature optimized radiation properties and should possibly be scarce in demand for space. In consequence, it would be an attractive opportunity for designers if antennas could fit into any arbitrary space available in small terminals, specifically in their upper parts. What becomes quite important is that some transmission methods require at least two antennas which must be mounted in the terminal. For these reasons we turned our attention to conformally shaped antennas which can be integrated into handheld terminals in a more flexible way.
{"title":"The effect of conformality on the electrical properties of small antennas","authors":"P. Kabacik, A. Kucharski","doi":"10.1109/APS.2001.960028","DOIUrl":"https://doi.org/10.1109/APS.2001.960028","url":null,"abstract":"One of the most desired innovations in modern antenna technology should be the widespread use of conformal designs. Antennas of this kind are expected to be applied primarily in arrays. However, another prospective application for conformal antennas is in handsets or other miniature terminals of mobile and wireless communications systems. The form of the handset and the range of available functions are the prerequisites of the phone market success. Furthermore, the terminal form is strongly related to a possibly large color display, which is no longer a tiny part of the device. Modern multimedia handsets call for multiband antennas, which should feature optimized radiation properties and should possibly be scarce in demand for space. In consequence, it would be an attractive opportunity for designers if antennas could fit into any arbitrary space available in small terminals, specifically in their upper parts. What becomes quite important is that some transmission methods require at least two antennas which must be mounted in the terminal. For these reasons we turned our attention to conformally shaped antennas which can be integrated into handheld terminals in a more flexible way.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128243890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The interaction of a transient electromagnetic pulse with an air layer in a dielectric medium is formulated in terms of a time-domain integral equation and solved numerically via the method of moments. Application of the standard marching-on-in-time approach in this case can not yield a solution. Hence, we utilize an implicit modeling scheme, and, to reduce the computational complexity, resort to a previously proposed time-domain impedance matrix compression method. This method uses spatio-temporal wavelet basis functions to construct and solve a reduced-rank matrix equation. Furthermore, by modeling the problem simultaneously at all the time steps, we can obtain a solution which roughly has the same level of accuracy for all these times.
{"title":"Transient analysis of air layer in a dielectric medium using wavelet-based implicit TDIE formulation","authors":"Y. Shifman, Y. Leviatan","doi":"10.1109/APS.2001.959516","DOIUrl":"https://doi.org/10.1109/APS.2001.959516","url":null,"abstract":"The interaction of a transient electromagnetic pulse with an air layer in a dielectric medium is formulated in terms of a time-domain integral equation and solved numerically via the method of moments. Application of the standard marching-on-in-time approach in this case can not yield a solution. Hence, we utilize an implicit modeling scheme, and, to reduce the computational complexity, resort to a previously proposed time-domain impedance matrix compression method. This method uses spatio-temporal wavelet basis functions to construct and solve a reduced-rank matrix equation. Furthermore, by modeling the problem simultaneously at all the time steps, we can obtain a solution which roughly has the same level of accuracy for all these times.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129313500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The NEMP associated with a high altitude nuclear burst can induce large currents and charges on computer hardware systems, high sensitivity instruments, communications networks, and military application systems such as aircraft, missiles, and satellites. In this paper, the time-domain moment method is used to calculate the electric field distributions inside a parallel plate NEMP simulator. The structure of the simulator system consists of the excitation source, the input and output tapered transition sections, the parallel plate transmission line, and the terminated load. The simulator is excited by a pulse form voltage having double exponential shape. We assume that the simulator is a transmission line with the usable test volume in the middle between the plates. The field at the dominant transverse electromagnetic mode (TEM) for such transmission lines is indistinguishable from that in free space propagation. The results of electric field distributions and time-response of the electric fields at 3 different locations inside the simulator are presented. The analysis of NEMP fields distributions will provide a valuable insight into parallel plate type NEMP simulators desirable for their design and use.
{"title":"Electric field distributions inside a parallel plate NEMP simulator by time-domain moment method","authors":"Hsing-Yi Chen, Bin Chang","doi":"10.1109/APS.2001.959425","DOIUrl":"https://doi.org/10.1109/APS.2001.959425","url":null,"abstract":"The NEMP associated with a high altitude nuclear burst can induce large currents and charges on computer hardware systems, high sensitivity instruments, communications networks, and military application systems such as aircraft, missiles, and satellites. In this paper, the time-domain moment method is used to calculate the electric field distributions inside a parallel plate NEMP simulator. The structure of the simulator system consists of the excitation source, the input and output tapered transition sections, the parallel plate transmission line, and the terminated load. The simulator is excited by a pulse form voltage having double exponential shape. We assume that the simulator is a transmission line with the usable test volume in the middle between the plates. The field at the dominant transverse electromagnetic mode (TEM) for such transmission lines is indistinguishable from that in free space propagation. The results of electric field distributions and time-response of the electric fields at 3 different locations inside the simulator are presented. The analysis of NEMP fields distributions will provide a valuable insight into parallel plate type NEMP simulators desirable for their design and use.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127330712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors proposed a circularly polarized conical beam spherical slot array antenna for applications of low bit rate or low gain/temperature ratio (G/T) land mobile satellite communication and broadcasting services in addition to wireless local area network base stations (see Krairiksh, M. et al., Int. J. Electronics, vol.86, no.7, p.815-23, 1999). The advantage of this antenna is that the structure is simple and suitable for mass production and the feeding structure is also simple. From preliminary results, the radiation pattern appears to be a conical beam (see Phongcharoenpanich, C. et al., IEICE Trans. Electronics, vol.E82-C, no.7, p.1242-7, 1999). This paper presents the theory and experiment of a circularly polarized conical beam spherical slot array antenna. The theoretical result is carried out by means of the method of moments. With the aid of the dyadic Green's function, the integral equations of the unknown currents are solved by using entire domain basis functions and Galerkin's method. The theoretical results of the radiation pattern, elevation angle and directivity, input impedance and axial ratio are illustrated. The experimental results agreed satisfactorily with the theoretical ones.
作者提出了一种圆极化圆锥波束球面缝隙阵列天线，用于低比特率或低增益/温度比(G/T)的陆地移动卫星通信和广播服务，以及无线局域网基站(见Krairiksh, M. et al.， Int.)。电子学报，第86卷，第86期。7，第815-23页，1999)。这种天线的优点是结构简单，适合批量生产，馈电结构也简单。从初步结果来看，辐射模式似乎是一个锥形光束(见Phongcharoenpanich, C. et al.， IEICE Trans。电子，vol.E82-C, no。7, p.1242-7, 1999)。本文介绍了圆极化圆锥波束球面缝隙阵列天线的原理和实验。用矩量法对理论结果进行了验证。借助并矢格林函数，利用全域基函数和伽辽金方法求解了未知电流的积分方程。给出了辐射方向图、仰角和指向性、输入阻抗和轴比的理论计算结果。实验结果与理论结果吻合得很好。
{"title":"Theory and experiment of a circularly polarized conical beam spherical slot array antenna","authors":"C. Phongcharoenpanich, M. Krairiksh, J. Takada","doi":"10.1109/APS.2001.960113","DOIUrl":"https://doi.org/10.1109/APS.2001.960113","url":null,"abstract":"The authors proposed a circularly polarized conical beam spherical slot array antenna for applications of low bit rate or low gain/temperature ratio (G/T) land mobile satellite communication and broadcasting services in addition to wireless local area network base stations (see Krairiksh, M. et al., Int. J. Electronics, vol.86, no.7, p.815-23, 1999). The advantage of this antenna is that the structure is simple and suitable for mass production and the feeding structure is also simple. From preliminary results, the radiation pattern appears to be a conical beam (see Phongcharoenpanich, C. et al., IEICE Trans. Electronics, vol.E82-C, no.7, p.1242-7, 1999). This paper presents the theory and experiment of a circularly polarized conical beam spherical slot array antenna. The theoretical result is carried out by means of the method of moments. With the aid of the dyadic Green's function, the integral equations of the unknown currents are solved by using entire domain basis functions and Galerkin's method. The theoretical results of the radiation pattern, elevation angle and directivity, input impedance and axial ratio are illustrated. The experimental results agreed satisfactorily with the theoretical ones.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130015263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Perry, C. Coleman, B.F. Basch, E. Rothwell, J. Ross
This paper investigates the use of a self-structuring antenna for television reception. Information about the received signal strength is obtained from the automatic gain control circuit of the television and used to determine the appropriate antenna structure. Because of the large number of possible configurations, a genetic algorithm is used to search for optimal switch arrangements. The antenna template and software were developed by undergraduate students at Michigan State University; refinement of the antenna by a core group of undergraduates is currently being undertaken.
{"title":"Self-structuring antenna for television reception","authors":"B. Perry, C. Coleman, B.F. Basch, E. Rothwell, J. Ross","doi":"10.1109/APS.2001.958817","DOIUrl":"https://doi.org/10.1109/APS.2001.958817","url":null,"abstract":"This paper investigates the use of a self-structuring antenna for television reception. Information about the received signal strength is obtained from the automatic gain control circuit of the television and used to determine the appropriate antenna structure. Because of the large number of possible configurations, a genetic algorithm is used to search for optimal switch arrangements. The antenna template and software were developed by undergraduate students at Michigan State University; refinement of the antenna by a core group of undergraduates is currently being undertaken.","PeriodicalId":159827,"journal":{"name":"IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130076447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229)
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