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Plasmaspheric and Enhanced Ionospheric Total Electron Content Monitoring

Award Information

Department of Defense
Air Force
Award ID:
Program Year/Program:
2004 / SBIR
Agency Tracking Number:
Solicitation Year:
Solicitation Topic Code:
Solicitation Number:
Small Business Information
NorthWest Research Associates, Inc.
P.O. Box 3027 Bellevue, WA 98009-
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Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Phase 1
Fiscal Year: 2004
Title: Plasmaspheric and Enhanced Ionospheric Total Electron Content Monitoring
Agency / Branch: DOD / USAF
Contract: FA8718-04-C-0009
Award Amount: $99,920.00


The integrated charge density through the ionosphere and plasmasphere along a line-of-sight, denoted Total Electron Content (TEC), is a quantity that influences the operation of various radio-frequency systems. Measurement of TEC is utilized in order to assess environmental or system impacts, with possibilities for correction or mitigation. The current primary source of TEC measurements is dual-frequency Global Positioning System (GPS) receiver systems. These measurements contain contributions from the ionosphere and the plasmasphere, as well as biases arising from instrumental sources. While plasmasphere charge densities are considerably less than those of the ionosphere, the large extent of the plasmasphere can produce a significant integrated contribution relative to that of the ionosphere. The instrumental biases can be of any magnitude. To achieve highly accurate TEC measurements, of the order of one TEC unit (1016 electrons/m2 for the integrated charge density), a highly accurate calibration technique, to eliminate the bias effects from the GPS TEC measurements, is required. Developments of a mathematical technique, based on observed characteristics of the ionosphere, have presented the opportunity for conducting separate measurements of the ionosphere and plasmasphere contributions to TEC. This proposal presents efforts to be undertaken for further developments and validation of this technique.

Principal Investigator:

Susan Rao
Research Scientist

Business Contact:

Joan Oltman-Shay
President/Sr. Research Scientiest
Small Business Information at Submission:

P.O. Box 3027 Bellevue, WA 98009

EIN/Tax ID: 911291143
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No