Sky-wave over-the-horizon radar (OTHR) propagates radio waves off the ionosphere to provide long-range surveillance around the Earth’s curvature. Frequency selection for high-latitude and polar OTHRs is challenging unless there is an environmental monitor that addresses the significant ionospheric variability in high-latitude regions, a spectrum monitor that finds unoccupied frequencies in the high-frequency (HF) radio waveband, and a frequency management system (FMS) that selects an optimal frequency from the merged results of the environmental monitor and spectrum monitor. This article describes the first FMS for high-latitude OTHR that merges results from the environmental monitor and spectrum monitor in real-time. The environmental monitor uses the assimilative Canadian high-arctic ionospheric model (A-CHAIM), which assimilates near-real-time data and is, to date, the most advanced ionospheric model for high-latitude regions. Despite remaining limitations, demonstrations of this real-time FMS between a transmitter and four targets during the day and night and during fall and summer show that it could be one of the tools for selecting frequencies for operational scenarios.

中文翻译：

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使用近实时电离层模型的超视距雷达 (OTHR) 频率管理系统 (FMS)


天波超视距雷达（OTHR）在电离层之外传播无线电波，以提供围绕地球曲率的远程监视。高纬度和极地 OTHR 的频率选择具有挑战性，除非有一个能够解决高纬度地区电离层显着变化的环境监测器、一个能够在高频 (HF) 无线电波段中找到未占用频率的频谱监测器以及一个频率监测器。管理系统（FMS），从环境监测器和频谱监测器的合并结果中选择最佳频率。本文介绍了第一个用于高纬度 OTHR 的 FMS，它实时合并环境监测器和频谱监测器的结果。环境监测仪采用加拿大高纬度电离层同化模型（A-CHAIM），该模型可近乎实时地同化数据，是迄今为止最先进的高纬度地区电离层模型。尽管仍然存在局限性，但在白天和夜间以及秋季和夏季期间发射机与四个目标之间的这种实时 FMS 的演示表明，它可以成为为操作场景选择频率的工具之一。