2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)最新文献_第2页

A summary of spectrum engineering, the why and how 摘要频谱工程，为什么和如何

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525038

E. Mokole, L. Cohen

{"title":"A summary of spectrum engineering, the why and how","authors":"E. Mokole, L. Cohen","doi":"10.1109/USNC-URSI-NRSM.2013.6525038","DOIUrl":"https://doi.org/10.1109/USNC-URSI-NRSM.2013.6525038","url":null,"abstract":"For many years, Electromagnetic Spectrum has been treated as a commodity within the United States, with allocation shared between Government and private sector interests. Government spectrum managers, working with their industry counterparts, carved out slices of spectrum under the governance of the Federal Communications Commission (FCC) and the National Telecommunications and Information Administration (NTIA) for commercial and government use, respectively. This relationship worked very well for many years due to the fact that electronic systems utilizing the spectrum, such as radar and satellite communications systems, were in designated bands. The solid-state revolution began to take hold aggressively in the early 1990s with an explosion of chip sets capable of performing the necessary functionality needed to support both the RF and signal processing infrastructures required for realizable high-speed wireless cellular communications. As the spectrum from UHF up through C band began to encounter greater congestion as a result of the influx of communications systems, the ability to manage a solution became rather tenuous at best. Since 2007 the US Navy has come to realize that in order to use spectrum, better engineering solutions are required to augment traditional spectrum management. These engineering solutions take the form of: (1) power amplifiers for radar and communications with lower levels of out-of-band emissions; (2) a waveform diversity approach for radar and communications that allow the requisite performance, but without adding to the out-of-band emissions; (3) antennas which support space-time diversity, thus allowing spectral compatibility in designated geographical zones; (4) adaptive software-defined receivers; and (5) bi-static/multi-static sensors, such as radars, that utilize the emissions of other users of the spectrum to support their operation.","PeriodicalId":123571,"journal":{"name":"2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115761453","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}

引用次数: 2

Radiation belt electron enhancements: History and new results from RBSP 辐射带电子增强:RBSP的历史和新结果

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525065

D. Baker, S. Kanekal, Xinlin Li, S. Elkington, H. Spence

{"title":"Radiation belt electron enhancements: History and new results from RBSP","authors":"D. Baker, S. Kanekal, Xinlin Li, S. Elkington, H. Spence","doi":"10.1109/USNC-URSI-NRSM.2013.6525065","DOIUrl":"https://doi.org/10.1109/USNC-URSI-NRSM.2013.6525065","url":null,"abstract":"Energetic electron data from low-altitude Earth-orbiting spacecraft show both a long historical record of the Van Allen radiation belts and the specific effects of powerful storms such as the 2003 Halloween storms. The fluxes of 2-6 MeV electrons measured by the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) from July 1992 to the current time are presented in this talk. Data demonstrate intense electron acceleration events (associated with high-speed solar wind), for example, in 1993-95 for 3 <; L <; 6. During sunspot minimum (1996), there were significant electron events only briefly around the spring and autumn equinoxes. The SAMPEX electron data for 2003 and throughout 2004 and 2005 show the shifted position of the outer Van Allen zone and the filling of the slot region (L<; 3). A persistent new belt of electrons was produced in the wake of the Halloween storms and this was clearly seen for L <; 2 for several years. We note that SAMPEX data demonstrate that in 2008 and 2009, the radiation belts virtually disappeared due to very weak solar wind driving conditions associated with the recent profound solar activity minimum period. Building on this historical record, we describe the new, exciting results from the Relativistic Electron-Proton Telescope (REPT) instrument that were launched successfully onboard the Radiation Belt Storm Probes mission on 30 August 2012. Key areas of scientific progress using REPT will be addressed. Excellent new data from the twin REPT instruments are available from the initial turn-on (Launch+3 days) of the instruments to the present. Inner and outer zone electron spectra have been compared with model expectations.","PeriodicalId":123571,"journal":{"name":"2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124256679","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}

引用次数: 1

Resolution analysis of a Radio Frequency Tomography system 射频层析成像系统的分辨率分析

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525056

V. Picco, T. Negishi, D. Erricolo

引用次数: 0

Signal quality in a multibeam transmit array 多波束发射阵列中的信号质量

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525005

R. Haupt, M. Weiss

引用次数: 0

A comparative study between CMA evolution strategies and Particle Swarm Optimization for antenna applications 天线应用中CMA演化策略与粒子群优化的比较研究

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525035

J. Kovitz, Y. Rahmat-Samii

引用次数: 2

Clustering and confidence intervals for radar target identification and estimation 雷达目标识别与估计的聚类与置信区间

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525103

R. Volz, S. Close, P. Erickson

引用次数: 0

Ion gyro-harmonic structuring in the stimulated radiation spectrum during third electron gyro-harmonic heating 第三电子陀螺调和加热过程中受激辐射谱中的离子陀螺调和结构

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525136

A. Mahmoudian, W. Scales, P. Bernhardt, S. Briczinski

引用次数: 0

Long recovery of the lower ionosphere from the quasi-electrostatic effects of cloud-tog-round lightning 云圆闪电准静电效应下电离层的长恢复

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6524971

Ningyu Liu

{"title":"Long recovery of the lower ionosphere from the quasi-electrostatic effects of cloud-tog-round lightning","authors":"Ningyu Liu","doi":"10.1109/USNC-URSI-NRSM.2013.6524971","DOIUrl":"https://doi.org/10.1109/USNC-URSI-NRSM.2013.6524971","url":null,"abstract":"Early VLF events with a long recovery time on the order of tens of minutes have been studied by several recent works [Cotts and Inan, GRL, 34, L14809, 2007; Haldoupis et al., JGR, 39, L16801, 2012; Salut et al., JGR, 117, A08311, 2012]. It has been suggested that the long recovery is caused by long-lasting conductivity perturbations in the lower ionosphere, which can be created by sprites/sprite halos triggered by cloud-to-ground (CG) lightning [Moore et al., JGR, 108, 1363, 2003; Haldoupis et al., 2012].We recently developed a two-dimensional fluid model with simplified ionospheric chemistry for studying sprite halos [Liu, JGR, 117, A03308, 2012]. The model chemistry captures major ion species and reactions in the lower ionosphere. The simulation results on sprite halos caused by positive CG lightning indicated when the electron detachment process from O- ions is included, electron density may grow even at subbreakdown conditions and the sprite halo front can descend to a lower altitude than previously thought. In this talk, we present the simulation results on the dynamics of sprite halos caused by negative CG lightning. For the halos caused by positive CG, their ionization fronts typically become very sharp as they descend downward, so simulations may suffer from numerical instability eventually [Liu, 2012]. However, the ionization front of a negative halo caused by lightning of similar strength is smoother, and the model can simulate the entire lifetime of the ionospheric perturbations. We show the modeling results on the ionospheric perturbations created by the negative halo and discuss how the ionosphere recovers to its original state.","PeriodicalId":123571,"journal":{"name":"2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122299732","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}

引用次数: 0

Link budget analysis for 350 GHz communication link 350ghz通信链路预算分析

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525077

S. Bhardwaj, N. Nahar, J. Volakis

{"title":"Link budget analysis for 350 GHz communication link","authors":"S. Bhardwaj, N. Nahar, J. Volakis","doi":"10.1109/USNC-URSI-NRSM.2013.6525077","DOIUrl":"https://doi.org/10.1109/USNC-URSI-NRSM.2013.6525077","url":null,"abstract":"Communication systems in the free band beyond 300 GHz are of interest for short distance communication. To assess the feasibility of such a communication system, a realistic link budget analysis is needed. Such link budget analyses have been conducted before based on TDS (optical) measurements and theoretical loss models. For this work, we present a more realistic link budget analysis based on the measurement of transmission losses using all electronic Tx-Rx system, operating from 325 to 500 GHz. It is well known that most losses in a THz communication are in free-space propagation channel between the transmitter and receiver. It is therefore essential to more accurately characterize these losses. To do so, we used a VDI Tx/Rx frequency extender system operating at 325 - 500 GHz generated from vector network analyzer. Using such a system, we characterized total link losses including combined effect of absorption losses, free-space losses, antennas losses and misalignment losses. A log linear model for the propagation was then constructed using linear regression analysis. Using the link characterization from these measurements, a communication link using commercially available WR-2.8 mixer and WR-5.1 frequency tripler devices (VDI) was simulated at 350 GHz in AWR-VSS/MATLAB. We conclude that, achievable data-rate of 20 Mbps is possible at a transmission distance of 8.5 m. However, data-rates upto 1 Gbps are possible using the dielectric lenses with the Tx and Rx antennas. Our estimates demonstrated that previously predicted link budgets are optimistic for an all-electronic system (using currently available components). Also, to maintain multi-Gbit link, high gain antenna structures would likely be required. At the conference, we will present the required antenna gains for longer link distances. This study will also explore various possible antenna choices to enhance antenna gains for such applications.","PeriodicalId":123571,"journal":{"name":"2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124994282","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}

引用次数: 1

MMW propagation in warm water evaporation ducts 毫米波在温水蒸发管道中的传播

2013 US National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM) Pub Date : 2013-06-06 DOI: 10.1109/USNC-URSI-NRSM.2013.6525052

F. Ryan

引用次数: 0