Improved Real-Time Ionospheric Compensation for Kwajalein Missile Range (KMR) Radars

ALTAIR range correction when dual-frequency tracking is unavailable, and ALTAIR elevation corrections with or without dual-frequency tracking depend critically on the accurate characterization of the ionosphere along the ray paths to the trajectory of the trced object. The techniques currently implemented at ALTAIR and other KWR radars do not reflect the advances in ionospheric modeling and sensor technology that hve become available during the last ten years. This proposal formulates an innovative advanced development program to upgrade these techniques and maximize radar tracking accuracy. The proposed work will analyze the capabilities of the most advanced low-latitude ionospheric model ---SLIM, FAIM, ICED, and PRISM -- for use in ALTAIR range and elevatio corrctions. Because significant spatial and temporal fluctuations of the ionosphere cannot be predicted by any model, a concept is developed to update the ionospheric model in real-time using a sensor integration approch which uses the capabilities made available by the Global Positioning Systms (GPS).