Browsing by Author "Gonzales, J."

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    Clustering and data reduction algorithm applied to spectra measured with a multi-static HF sounding system in Peru
    (2023 CEDAR Workshop, 2023-06) Vásquez, V.; Milla, M.; Kuyeng, Karim; Gonzales, J.; Scipión, Danny
    The HF radar is a network of HF radio beacons and receivers for ionospheric sounding, and it 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. To improve the quality of the spectral data, two changes were made. The first one involved transmitting frequencies separated by 3.3 Hz in each transmission station, which allowed to spectrally separate and identify the signals coming from a given station, displacing the cross-talk in frequency but not eliminating it. Therefore, the second change was made, which corresponds to the development of an algorithm that extracts only the signals of interest from the measured spectrum. It is capable of detecting clusters of data in the spectra classifying them as coherent echoes, while noise sectors are discarded. The algorithm procedure and the comparisons of the spectra and final data are shown in this work.
    Palabras clave:HF radarCoherent echoesMultifrequency transmitting
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    Quality improvements to the spectral data acquired from HF multi-static sounding system at the magnetic Equator
    (2023 SWOL Workshop, 2023-10) Vásquez, V.; Milla, M.; Kuyeng, Karim; Gonzales, J.; Scipión, Danny
    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.
    Palabras clave:HF radarCoherent echoesMultifrequency transmitting