REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

One solution of real-time spectrum segmentation in HF direction finder based on time-frequency-space analysis

UgljeŠa DragiŠiĆ

RT-RK Computer Based Systems LLC, Novi Sad, ugljesa.dragisic@rt-rk.com

Goran kruniĆ

RT-RK Computer Based Systems LLC, Novi Sad, goran.krunic@rt-rk.com

nikola tesliĆ

Faculty of Technical Sciences at University of Novi Sad, Novi Sad, Nikola.Teslic@rt-rk.com

Abstract: Beside human intelligence that follow graphic results of modern HF direction finder and decide about emissions, emitters, communication channels and emitters network there is try to support that decisions using algorithm that parse information from digital data. The goal is to make more efficient algorithm that catch, decide and measure most of emissions, and less of parasite or fake emissions with list possible knowledge about signal characteristics. Spectrum segmentation in one frame chooses emission segments with same azimuth indicated with signal level. Selected segments are grouped to indicate existing emissions or added by rule to formed emissions. Rule that regulate adding segments to emissions is ordered by emission type. Emissions by type that can be separated from spectrum are fixed narrow band, burst, frequency hopping, frequency chirp and direct sequence signal spectrum emission. To measure efficiency we used mathematical generated pseudorandom signal data with known signal characteristics and field recordings of signal generators and emitters with known characteristics. Created algorithm could be used to detect segments from HF direction finder, but results mostly depend on expert knowledge for setting parameters and removing parasite emissions.

Keywords: Segmentation, HF direction finder, algorithm.