Global Positioning System Receiver for Monitoring Ionospheric Total Electron Content

摘要

A system has been built around a dual-frequency NovAtel MiLLenniumTM Global Positioning System (GPS) receiver in order to measure the Total Electron Content (TEC) of the ionosphere and to detect radio wave scintillation. The software has been designed and developed to provide interactive control of the receiver and the logging of its data to an external removable disk. In addition, it features a graphical user interface which includes displays both in real-time and for the previous 24 hours of satellite locations and measured TEC values. Adequate calibration of TEC values is widely recognised as a difficult problem and in this implementation, calibration of the real-time results has been achieved satisfactorily to first order. The real-time displays make the equipment particularly useful for campaigns, but the more useful application is for routine unattended logging. Two systems have been deployed, one each in Malaysia and Indonesia under the Regional Engagement program. The intent is to monitor both ionospheric behaviour and GPS performance in equatorial regions as we approach the next peak in solar cycle activity in about the year 2000.