Limitations in GPS reciever tracking performance under ionospheric scintillation conditions

GPS receiver tracking performance can be degraded during periods of enhance d ionospheric activity when small-scale scintillation effects (phase and am plitude variations) may be observed in the high latitude auroral region and the low latitude equatorial anomaly region. During periods of intense scin tillation the availability of carrier phase observations may be limited thr ough loss of signal lock, with a significant impact on precise positioning applications. Such effects have a larger impact on the L2 tracking performa nce where codeless and semi-codeless technologies are employed to extract t he encrypted L2 signal. The tracking performance of a given receiver depends not only on the magnit ude of scintillation activity observed, but also on the receiver tracking c apabilities. Tracking performance can vary significantly between receivers under identical scintillation conditions. In this paper the impact of scint illation effects on GPS receiver tracking performance is investigated in bo th the equatorial and high latitude aurora! regions. A comparison of receiv er technologies is also conducted using both codeless and semi-codeless GPS receivers. Performance comparisons and tracking statistics are established and interpreted with respect to GPS network applications and the availabil ity of GPS observations at solar maximum. (C) 2001 Elsevier Science Ltd. Al l rights reserved.