DURIP Application of Multiprocessing to Real-Time Analysis and Control of anIonospheric Research Radar

摘要

The utilization of high-frequency (HF) radio waves to probe the ionosphere wasbegun more than 50 years ago when the first swept frequency vertical incidence ionospheric sounder (ionosonde) was developed (see Villard, 1976). A technology evolved, so did the design of ionospheric sounders and several generations of sounders have been developed. As a result, the ionosonde has continued to remain a viable tool for the ionospheric physicist and vast amounts of ionospheric data have been collected. Over the past two decades, with the incorporation of digital technology into ionosondes, more sophisticated ionospheric sounders have been developed, with the capability of measuring the amplitude, phase, angle-of-arrival, polarization and Doppler shift in addition to the time-of-flight (ie. range) of the returned echo (Wright and Fedor, 1969; Reinisch, 1986). These systems have also employed digital recording techniques, markedly simplifying hte analysis interpretation of ionograms. Here, details of the NOAA digital ionospheric sounding radar and the Lowell University Digisonde will be discussed briefly as the design concepts are representative of state-of-the-art ionospheric sounders. (rh)