American Journal of Electrical and Electronic Engineering
ISSN (Print): 2328-7365 ISSN (Online): 2328-7357 Website: Editor-in-chief: Naima kaabouch
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American Journal of Electrical and Electronic Engineering. 2018, 6(3), 90-92
DOI: 10.12691/ajeee-6-3-3
Open AccessArticle

Switched Beam through Parasatic Antenna Array for Radio Direction Finding Using I/Q Samples

Ahmed Siddig Ibrahim Mustafa1, Mohammed Almoiz Abd-Almoniem Mohammed1 and Nassrin Ibrahim Mohamed Elamin1,

1Department of Electrical and Electronic Engineering (Telecommunication), Faculty of Engineering, International University of Africa, Khartoum, Sudan

Pub. Date: November 13, 2018

Cite this paper:
Ahmed Siddig Ibrahim Mustafa, Mohammed Almoiz Abd-Almoniem Mohammed and Nassrin Ibrahim Mohamed Elamin. Switched Beam through Parasatic Antenna Array for Radio Direction Finding Using I/Q Samples. American Journal of Electrical and Electronic Engineering. 2018; 6(3):90-92. doi: 10.12691/ajeee-6-3-3


An electronically controlled parasitic antenna array consisting of one active element connected to a software defined radio (SDR) receiver and four passive parasitic elements used to design and construct affordable radio direction finding system. The directivity of the antenna array achieved by increasing/degreasing the electrical length of the parasitic elements. The design based on a central active monopole and an array of four parasitic monopoles equidistantly from the central element by 0.20 λ, placed on ground plane to provide the 360 degree azimuthal coverage without any moving parts, provides excellent directional resolution. The system is controlled by using Arduino to switch between regions (0-90),(90-180),(180-270) or (270-360) and analysed by using a newly developed method based on I/Q samples to extract the amplitude and phase of the desired signal to find the exact direction in that region. The antenna design, its application to determine the direction finding, the new algorithm are presented below.

RDF AoA parasitic monopoles

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