Alouette-2 Topside Sounder Average Ionogram over Quito, Equador: QUI, Latitude -1, Longitude 281

This Ionogram was digitized from the original Alouette 2 Analog Telemetry Data on 7-Track Tape using the Facilities of the Data Evaluation Laboratory at NASA GSFC, Code 500. This Data Restoration Project is headed by Dr. R.F. Benson, NASA GSFC, Code 692. Ionograms were digitized at the Rate of 40,000 16-bit samples/s. This Sample Rate is higher than the Nyquist Frequency of 30 kHz. The Sample Frequency of 40 kHz provides a Measurement every 25 ms corresponding to an Apparent Range Interval of c*t/2, where c is the Speed of Light, or 3.747 km. Each Ionogram consists of a Fixed Frequency Portion and a Swept Frequency Portion. The Time Resolution is typically 31 s.

本离子图系由美国国家航空航天局（NASA）戈达德航天中心（GSFC）数据评估实验室（Code 500）提供的设施，从原始的阿卢特2号（Alouette 2）模拟遥测数据磁带上进行数字化处理而成。此数据恢复项目由NASA GSFC的R.F. Benson博士（Code 692）领导。离子图以每秒40,000个16位样本的速率进行数字化。此采样率高于30 kHz的奈奎斯特频率。40 kHz的采样频率提供了每25毫秒的测量值，对应于光速c乘以时间t的一半（c*t/2），其中c为光速，约为3.747公里。每个离子图由一个固定频率部分和一个扫描频率部分组成。时间分辨率通常为31秒。