Accession Number : ADA260982


Title :   Theoretical Study of Topside Ionospheric Clutter


Descriptive Note : Final rept. 28 Mar 90-27 Mar 92,


Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE


Personal Author(s) : Lee, Min-Chang ; Groves, Keith M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260982.pdf


Report Date : 15 Jul 1992


Pagination or Media Count : 117


Abstract : The sponsored research is aimed at understanding the small scale topside ionospheric plasma structures first observed at Millstone Hill, Massachusetts with the 440 MHz incoherent scatter radar. These small scale obliquely propagating plasma modes occurring in the vicinity of the mid-latitude ionospheric trough, have large radar cross-sections and narrow spectral widths. They have, until recently, been dismissed solely as hard target contamination of the incoherent scatter radar. The geophysical conditions associated with the ionospheric trough, such as the field aligned current activity and steep plasma density gradients, suggest that these recently discovered small scale topside ionospheric plasma structures may also appear in the auroral and polar regions. This speculation has been corroborated by our preliminary experiments and data analyses at Tromso, Norway and Sondrestromfjord, Greenland. Presented in this final report are our research results and Arecibo experiments simulating the geophysical conditions of generating these topside ionospheric plasma structures. Recommendation for the future research is also given.... Enhanced Radar Backscatter (ERB), Ion acoustic waves, Langmuir wave turbulence, Particle precipitation, Field aligned currents. Wave-wave coupling processes.


Descriptors :   *RADAR CLUTTER , *ACOUSTIC SCATTERING , *RADIO SIGNALS , *IONOSPHERIC DISTURBANCES , IONS , POLAR REGIONS , DENSITY , PLASMAS(PHYSICS) , ACOUSTIC WAVES , TURBULENCE , RADAR , GEOPHYSICS , PLASMASPHERE , TROUGHS , GREENLAND , LATITUDE , COUPLINGS , GRADIENTS , RADIOFREQUENCY , INCOHERENT SCATTERING , BACKSCATTERING , PRECIPITATION , PARTICLES , ELECTROMAGNETIC RADIATION , CROSS SECTIONS , RADAR CROSS SECTIONS , AURORAE


Subject Categories : Atmospheric Physics
      Active & Passive Radar Detection & Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE