TGO Ramfjordmoen Ionosonde Data November 1990

About this dataset: This dataset contains ionograms in PNG format and covers data from November 01-30, 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：本数据集包含以 PNG 格式存储的电离层图，涵盖了 1990 年 11 月 1 日至 30 日之间的数据。关于特罗姆瑟电离层仪（1984-1992）：在 1984-1992 年期间，特罗姆瑟电离层仪位于挪威特罗姆瑟市 69° 35' N, 19° 13' E 的 Ramfjordmoen，由特罗姆瑟大学的极光观测站操作。该仪器在 1984 年之前在此地运行，截至 2018 年仍在运行；具体细节请参阅相关出版物。该仪器完全数字化，基于惠普 21MX 计算机。低功率发射机和互补码传输的结合使得特罗姆瑟电离层仪在当时等同于具有 20 微秒脉冲和 16 千瓦峰值功率的传统电离层仪。常规操作为每 20 分钟进行一次电离层图绘制，频率扫描从 1 兆赫兹到 12 兆赫兹，持续时间为 2 至 3 分钟。对于 100 公里高度层，确定稀疏 E 层高度精度为 ± 3 公里。电离层图存储在磁带上。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%。通过这种方式，一条 2400 英尺的磁带可以存储大约 1300 张电离层图，相当于 18 天的数据。读取时，磁带已存放 4-11 年，因此在转移到其他媒体的过程中导致约 20% 的数据损失。如今，数据存储在在线磁盘上，并在离线状态下存档于多种媒体之中。