融入电离层先验信息的短波超视距直接定位算法

Shortwave Over-the-Horizon Direct Position Determination Algorithm Incorporating Ionospheric Height Prior Information

摘要:

针对短波超视距定位中因电离层虚高测量误差导致定位精度下降的问题，开展了基于电离层虚高先验信息的直接定位算法研究。该算法基于直接定位模型，利用短波单站测向定位确定目标的初始网格范围，并结合国际参考电离层模型与电离层测高仪数据获取电离层虚高先验信息，通过将虚高信息嵌入电离层单层镜面反射模型，建立更精确的信号传播路径模型，避免不同传输路径虚高差异引起的定位偏差，实现高精度定位。实验结果表明，与传统固定虚高假设下的直接定位算法相比，所提方法在典型场景下将定位误差降低了5~25 km，提升了短波超视距定位系统的稳定性和精度水平。

Abstract:

To address the issue of degraded positioning accuracy caused by ionospheric virtual height measurement errors in over-the-horizon high-frequency positioning, a direct localization algorithm incorporating prior information on ionospheric virtual height was developed. Based on the direct localization model, the initial target grid range was determined using single-site direction-finding technology. Ionospheric virtual height prior information was obtained by combining the International Reference Ionosphere model with ionosonde measurements. By embedding this virtual height information into the single-layer specular reflection model, a more accurate signal propagation path model was established, effectively mitigating localization deviation caused by variations in virtual height across different propagation paths and thereby achieving high-precision positioning. Experimental results demonstrate that, compared to traditional direct localization algorithms based on fixed virtual height assumptions, the proposed method reduces positioning errors by 5–25 km in typical scenarios, significantly improving the stability and accuracy of the over-the-horizon high-frequency positioning system.