Abstract

Determination of the direction of the signal arrival (DOA) finds many applications in various areas of science and industry. Knowledge of DOA is used, among others to determine the position of a satellite with a low Earth orbit (LEO), localization of people and things as well as in research of wireless communication systems, for instance the determination of the number of signal sources in a various propagation environments. The interest of the scientific community and industry in DOA issues is gaining importance due to 5G technology, where the location of the signal source is crucial in areas such as the Internet of Things or Smart Cities.

The subject of the work is a system for determining the direction of signal arrival in the 2.4 GHz band using the electronically steerable parasitic array radiator (ESPAR) and software defined radio (SDR) technology. Three group of DOA algorithms were chosen which are based on conventional beamforming technology, subspace method and maximum likelihood. Simulations of selected algorithms were performed in order to compare the effectiveness of estimating the angle of impinging signal. The MUSIC algorithm (MUltiple SIgnal Classification) was used together with an ESPAR antenna. A demonstrator presenting the operation of the MUSIC algorithm was prepared, enabling the reading of antenna radiation characteristics from a text file, choosing number of snapshots and sweeping between various signal to noise ratio (SNR ) values. In the anechoic chamber measurements were made using the ESPAR antenna and software defined radio. The results of the simulation were compared with the results of measurements. A modification of the MUSIC method based on signal strength has been proposed. The results of the modified algorithm were compared with the PPCC algorithm (Power Pattern Cross Correlation), which is also based on signal strengths and is presented widely in the literature.

Acknowledgement: This paper is a result of the SCOTT project (www.scott-project.eu) which has received funding from the Electronic Component Systems for European Leadership Joint Undertaking under grant agreement No 737422. This Joint Undertaking receives support from the European Union’s Horizon 2020 research and innovation programme and Austria, Spain, Finland, Ireland, Sweden, Germany, Poland, Portugal, Netherlands, Belgium, Norway.

The document reflects only the author’s view and the Commission is not responsible for any use that may be made of the information it contains.

Author (1)