Quality improvements to the spectral data acquired from HF multi-static sounding system at the magnetic Equator

Abstract

A network of HF radio beacons and receivers for ionospheric sounding has been operating in Peru since 2016. The purpose of this instrument is to measure the group delay, Doppler shift, power, and other parameters in order to estimate the regional plasma density as a function of space and time, this information is crucial for forecasting the occurrence of Spread-F. The HF radar used only one frequency for transmission and reception that generated interference between different transmitter stations in the analyzed spectrum. To improve the quality of the spectral data, changes were made to the operation of the radar. Spectral separation of the transmitted signals was carried out, followed by the implementation of an algorithm that extracts only the signals of interest from the measured spectrum, discarding the noisy areas. The procedure for the changes made to the HF system, along with comparisons of the final data, is shown in this work.