Daily ionospheric forecasting service (DIFS) III

摘要

The daily variability of the ionosphere can greatly affect HF or SATCOMcommunications. HF skywave operators plan frequency schedules months inadvance, however, they also require daily knowledge of the ionosphericconditions in order to modify assignments. SATCOM operators also requiredaily information about the levels of scintillation, which are variations inphase, amplitude, polarisation and angle of arrival that can cause severedegradation of the received signal.

Using a number of ionosonde measurements and geomagnetic and solar values, aDaily Ionospheric Forecasting Service (DIFS) has been developed, whichprovides HF and SATCOM operators with daily forecasts of predictedionospheric conditions. The system uses in-house algorithms and anexternally developed Global Ionospheric Scintillation Model (GISM) togenerate HF and SATCOM forecasts. HF forecasts consist of a past summary anda forecast section, primarily displaying observed values and predictedcategories for the Maximum Usable Frequency (MUF), as well as an IonosphericCorrection factor (ICF) that can be fed into the ionospheric propagationprediction tool, WinHF. SATCOM forecasts give predictions of globalscintillation levels, for the polar, mid and equatorial latitude regions.Thorough analysis was carried out on DIFS and the results conclude that theservice gives good accuracy, with user feedback also confirming this, aswell.