TGO Ramfjordmoen Ionosonde Data January 1990

About this dataset: This dataset contains ionograms in PNG format and covers data from January 01-31, 1990.About the Tromsø Ionosonde (1984-1992): During the period 1984-1992 the Ionosonde was situated at 69° 35' N, 19° 13' E at Ramfjordmoen near Tromsø, Norway and operated by the Auroral Observatory of the University of Tromsø. The instrument operated at this location prior to 1984, and still operates there (as of 2018); see the related publication for details. The instrument was fully digitized and based on a Hewlett Packard 21MX computer. The combination of a low power transmitter and complementary code transmission made the Tromsø ionosonde equivalent to a conventional ionosonde (at the time) with 20 µs pulses and 16 kW peak power. Routine operation was one ionogram every 20 min with a frequency sweep from 1 MHz to 12 MHz lasting between 2 and 3 min. For the 100 km altitude region the precision of determining the height of a sporadic E layer is ± 3 km. The ionograms were stored on magnetic tape. A noise discrimination routine in the computer program reduced the stored data to less than 10% of the raw data. In this way one 2400' tape held about 1300 ionograms, equivalent to 18 days' data. The tapes were 4-11 years old when they were read, resulting in around 20% data-loss during the process of transferring to other media. Today, storage is on online disk and with offline an archive on a variety of media.

关于本数据集：该数据集包含以 PNG 格式存储的离子图，并涵盖了 1990 年 1 月 1 日至 31 日的数据。关于特隆赫姆电离层声测仪（1984-1992）：在 1984-1992 年期间，特隆赫姆电离层声测仪位于挪威特隆赫姆附近拉姆富尔登，纬度 69° 35'，经度 19° 13'，由特隆赫姆大学极光观测站运营。该仪器在 1984 年之前就已在此地运行，且截至 2018 年仍在运行；有关详细信息，请参阅相关出版物。该仪器基于惠普 21MX 计算机，实现了全面数字化。低功率发射机和互补码传输的组合使得特隆赫姆电离层声测仪在当时等同于常规电离层声测仪，具有 20 微秒脉冲和 16 千瓦峰值功率。常规操作为每 20 分钟生成一张离子图，频率从 1 兆赫兹扫描至 12 兆赫兹，持续时间为 2 至 3 分钟。对于 100 公里高度区域，确定突发 E 层高度的精度为 ± 3 公里。离子图存储在磁带上。计算机程序中的噪声识别程序将存储数据减少至原始数据的不到 10%。以此方式，一张 2400 英尺的磁带可以存储大约 1300 张离子图，相当于 18 天的数据。当读取磁带时，这些磁带已经存储了 4-11 年，因此在转换为其他媒体的过程中造成了大约 20% 的数据丢失。如今，存储介质为在线磁盘，并拥有离线存储于多种媒体上的档案。