Real-time anomaly monitoring method suitable for single-station ionized layer TEC

Abstract

A single station ionized layer TEC real-time anomaly monitoring method comprises the steps that firstly, a global map drawing file provided by a European orbit determination center CODE is obtained, and ionized layer vertical TEC at the position where an observation single station is located is obtained through spherical harmonic function expansion and inclination factors; setting a window length, a subsequence length, a principal component number and an error threshold parameter, selecting a TEC historical time sequence, a magnetic storm and other abnormal space precursor in a calm period of the solar activity and the geomagnetic activity as a to-be-monitored sequence, performing singular value decomposition by using Lanczos and QR, and adjusting the parameter to determine an optimal solution according to an abnormal monitoring correct rate and a false detection rate; and carrying out real-time TEC sequence data flow monitoring by utilizing the optimized parameters. According to the method, the accuracy and real-time performance of ionosphere TEC anomaly recognition can be improved, high-quality service is provided for a satellite-ground radio wave propagation engineering system, scientific and reasonable space environment anomaly monitoring can be constructed, and the pre-earthquake medium and short term forecasting technology of a great earthquake is enriched.

Description

technical field [0001] The invention relates to an ionospheric TEC anomaly monitoring method, in particular to a real-time anomaly monitoring method applicable to a single-station ionospheric TEC, and belongs to the technical field of ionospheric space environment forecasting. Background technique [0002] The ionosphere 60-1000km away from the earth's surface contains a large number of ions and free electrons. Under the combined action of solar rays, cosmic rays and other falling ions, the ionosphere will reflect or refract the radio waves passing through it. Additional delays are generated on the link, which reduces the service performance of various space application systems such as remote sensing and telemetry, navigation and positioning, and over-the-horizon radar. The ionospheric additional delay can usually be attributed to the total electron concentration TEC in the direction of the satellite-receiver line of sight. Therefore, eliminating the additional time delay i...

AI Technical Summary

Problems solved by technology

Traditional mathematical statistical methods represented by autoregressive moving average model ARIMA and sliding interquartile range use the statistical characteristics of normal activities to establish a norm distribution, and use statistical tests to determine whether the observed TEC parameters deviate significantly from the norm distribution. The advantage of the class method is that it can identify outliers that deviate from normal values, but has a high false positive rate

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