irAn 's 'tJ n J/ aY I, NATIONAL ACADEMIES OF SCIENCES AND ENGINEERING NATIONAL RESEARCH COUNCIL of the UNITED STATES OF AMERICA UNITED STATES NATIONAL COMMITTEE International Union of Radio Science National Radio Science Meeting 4 - 7 January 2006 Sponsored by USNC/URSI University of Colorado at Boulder Boulder, Colorado USA United States National Committee International Union of Radio Science ABSTRACTS National Radio Science Meeting 4-7 January 2006 University of Colorado, Boulder Sponsored by USNCjURSI Table of Contents Session Page No. Session Page No. Membership Information ...... iii F2 ....................... 157 Description of URSI ......... iv F3 ....................... 163 Plenary Session ............. vii G1 ...................... 171 Al ........................ 1 G2 ...................... 185 A2 ........................ 7 G3 ...................... 199 A/Dl ..................... 15 G4 ...................... 211 B1 ....................... 23 G/H1 .................... 221 B2 ....................... 31 G/H2 .................... 235 B3 ....................... 39 G/H3 .................... 247 B4 ....................... 47 HI ...................... 257 B5 ....................... 61 H/G1 .................... 269 B6 ....................... 73 H/G2 .................... 279 B7 ....................... 81 H/G3 .................... 291 B/E1 ...................... 89 ]1 ....................... 299 B/F1 ...................... 97 J2 ....................... 309 B/F2 ..................... 105 J3 ....................... 321 B/F3 ..................... 117 J/B1 ..................... 335 C1 ...................... 125 J/B2 ..................... 349 D1 ...................... 133 K1 ...................... 361 E1 ....................... 139 K2 ...................... 367 Fl ....................... 145 Index .................... 379 ii Membership United States National Committee INTERNATIONAL UNION OF RADIO SCIENCE Chair: Piergiorgio L.E. Uslenghi * Secretary & Chair-Elect: Yahya Rahmat-Samii* Immediate Past Chair: Umran S. Inan* Treasurer: Gary S. Brown Members Representing Societies, Groups, and Institutes: American Astronomical Society: Donald Backer American Geophysical Union: David Hysell American Meteorological Society: Richard J. Doviak IEEE Antennas and Propagation . Society: Susan C. Hagness IEEE Geosciences and Remote Sensing Society: Edgeworth R. Westwater IEEE Microwave Theory and Techniques Society: Tatsuo Itoh Members-at-Large Susan C. Hagness Steven C. Reising Jennifer T. Bernhard Paul A. Bernhardt Jacqueline Hewitt Nader Engheta Yahya Rahmat-Samii Robert Gardner Chairs of the USNC-URSI Commissions: Commission A Vijay Nair Commission B David R. Jackson Commission C Dev Palmer Commission D L. Wilson Pearson Commission E Cynthia Ropiak Commission F Roger Lang Commission G John Matthews Commission H Meers Oppenheim Commission J David Woody Commission K Gianluca Lazzi Officers, Chairs and Vice Chairs of Commissions of URSI residing in the United States URSI Honorary President William E. Gordon URSI Vice President Chalmers M. Butler Chair, Commission C A. F. Molisch Vice Chair, Commission D Franz Kartner *Member ofUSNCjURSI Executive Committee iii Description of the International Union of Radio Science The International Union of Radio Science is one of the world scientific unions organized under the International Council of Scientific Unions (ICSU). It is commonly designated as URSI from its French name, Union Radio Scientifique Internationale. Its aims are (1) to promote the scientific study of radio communications, (2) to aid and organize radio research requiring cooperation on an international scale and to encourage the dis­ cussion and publication of the results, (3) to facilitate agreement upon com­ mon methods of measurement and the standardization of measuring instru­ ments, and (4) to stimulate and to coordinate studies of the scientific aspects of telecommunications using electromagnetic waves, guided and unguided. The International Union itself is an organizational framework to aid in promoting these objectives. The actual technical work is largely done by the National Committee in the various countries. The officers of the International Union are: President: Fran<;:ois Lefeuvre (France) Past President: Kristian Schlegel (Germany) Vice Presidents: Chalmers M. Butler (USA) Gert Brussaard (Netherlands) Martti Hallikainen (Finland) Phil Wilkinson (Australia) Secretary -General: Paul Lagasse (Belgium) Assistant Secretary General: Femke Olyslager (Belgium) Assistant Secretary General (Publications): W. Ross Stone (USA) Executive Secretary: Inge Heleu (Belgium) Administrative Secretary Inge Lievens (Belgium) The Secretary General's office and the headquarters of the organization are located c/o INTEC, Ghent University, Sint-Pietersnieuwstraat 41, B-9000 Ghent, Belgium. The Union is supported by contributions (dues) from 44 member committees. The International Union, as of the XXVIIIth General Assembly held in New Delhi, India, 23-29 October, 2005, has ten bodies, called Commissions, for centralizing studies in principal fields. Every three years the International Union of Radio Science holds a meet­ ing called the General Assembly. The next is the XXIXth, to be held in Chicago, Illinois, USA, on 7-16 August, 2008. The Secretariat prepares and distributes the Proceedings of the General Assemblies. The International Union arranges international symposia on specific subjects pertaining to the work of one or several Commissions and also cooperates with other Unions in international symposia on subjects of joint interest. iv Radio is unique among the fields of scientific work in having a specific adaptability to large-scale international research programs, since many of the phenomena that must be studied are worldwide in extent and yet are in a measure subject to control by experimenters. Exploration of space and the extension of scientific observations to the space environment are depend­ ent on radio for their research. One branch, radio astronomy, involves cos­ mic phenomena, URSI thus has a distinct field of usefulness in furnishing a meeting ground for the numerous workers in the manifold aspects of radio research; its meetings and committee activities furnish valuable means of promoting research through exchange of ideas. Steering Committee: P.L.E. Uslenghi, University of Illinois at Chicago K. Grosland, CU Conference Services, University of Colorado Technical Program Committee: P. Uslenghi, Chair Y. Rahmat-Samii, Secretary S. Reising, Student Paper Competition (A) v. Nair (F) R. Lang (B) D. Jackson (G) J. Matthews (C) D. Palmer (H) M. Oppenheim (D) L.W. Pearson (J) D. Woody (E) C. Ropiak (K) G. Lazzi v Plenary Plenary Session, 10: 15 - Thurs. Gasiewski, A.J., Clegg, A.W. vii Plenary Plenary-! SPECTRUM MANAGEMENT AND INTERFERENCE MITIGA­ TION IN PASSIVE EARTH REMOTE SENSING Gasiewski, AJ.Q 1 NOAA Environmental Technology Laboratory, Boulder, CO, USA 2Department of Electrical and Computer Engineering, University of Colorado, Boulder, CO, USA Increasing use of previously quiet radio bands for communications and radar applications imposes a growing problem for passive remote sensing of many key en­ vironmental variables, including soil moisture, sea surface temperature, water vapor, ocean surface winds, cloud water content, and rain rate. We review in this talk the status of major passive microwave environmental observing systems, sensitivity and spectral requirements for Earth remote sensing, useful RFI mitigation techniques, and major regulatory issues affecting passive Earth remote sensing. The problem of anthropogenic radio frequency interference (RFI) in passive Earth remote sensing is similar to that of RFI in radio astronomy, thus engender­ ing a mutual interest among users of the Earth Exploration Satellite Service (EESS) and Radio Astronomy Service (RAS) to regulate emissions in several key bands of common interest. Being that the two services are based upon distinct viewing ge­ ometries and locations, integration times, spectral features, and applications of the data, however, there are a number of vexing issues specific to Earth remote sens­ ing. Foremost among these distinctions is the need in passive Earth remote sensing to maintain interference-free operation while regularly viewing downward over the entire globe, including (and especially) major urban and coastal areas. In addition, certain key bands necessary for passive microwave surface observation have never been provided primary EESS allocation. Progress over the past several years in developing RFI mitigation techniques for passive Earth remote sensing has been substantial, and the use of such tech­ niques promises to at least temporarily sustain environmental observation capabili­ ties. Countering this trend, we anticipate that new applications of passive microwave sensors relying upon direct assimilation of data into modem numerical models will further magnify the impact of RFI as these models improve their representational accuracy. ix Plenary-2 DC TO DAYLIGHT: SPECTRUM MANAGEMENT AND THE NEW RADIO ASTRONOMY Clegg, A. W. National Science Foundation, 4201 Wilson Blvd, Arlington VA 22230 Radio astronomers are increasingly outfitting existing radio telescopes with the capability to acquire data well outside of bands allocated to the radio astronomy service. Envisioned next-generation radio telescopes, such as the Square Kilometer Array, will go one step further by requiring this capability to carry out some of their fundamental scientific goals. At the