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LEO Satellite Feeding System: Design and Analysis

Title:

LEO Satellite Feeding System: Design and Analysis

Gadelrab, Mahmoud ORCID: https://orcid.org/0000-0001-7581-4664 (2023) LEO Satellite Feeding System: Design and Analysis. Masters thesis, Concordia University.

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Abstract

Satellite networks, particularly LEO satellites, are gaining prominence in wireless communication due to their global coverage and mobility capabilities. These systems often employ dual-polarized antennas, supplemented by Orthomode Transducers (OMTs) for efficient signal feeding and isolation management. Circularly polarized waves find extensive use in modern communication systems, facilitated by polarizers for phase shift generation. Corrugated horn antennas, known for their reliable performance, are a favored choice in satellite systems, catering well to the demands of LEO satellite applications.
The main purpose of this thesis is to design a circular polarized satellite-feeding structure for Low Earth Orbit (LEO). The major components addressed in this thesis are the Orthomode Transducer, Polarizer, and Corrugated Horn Antenna. The proposed system is a wideband system covering a bandwidth ratio of about 53%. Moreover, the proposed OMT is studied in terms of critical design considerations to test its compatibility with satellite applications like passive intermodulation,
thermal analysis, and vacuum breakdown analysis. The polarizer covers this band as well while keeping a flat phase shift response of about 90◦ ± 7◦. The overall integrated system is separated into two bands the transmitted and receiving band using a commercial diplexer. The overall structure complies with the LEO satellite feeding structure and achieves an axial ratio of 0.6 dB and the radiation patterns have a tapering value of about 18 dBi.

Divisions:Concordia University > Gina Cody School of Engineering and Computer Science > Computer Science and Software Engineering
Item Type:Thesis (Masters)
Authors:Gadelrab, Mahmoud
Institution:Concordia University
Degree Name:M.A. Sc.
Program:Electrical and Computer Engineering
Date:30 November 2023
Thesis Supervisor(s):Sebak, Abdelrazik and Shams, Shoukry
Keywords:Axial Ratio Geostationary Earth Orbit Global System for Mobile Communication Insertion Loss Isolation Low Earth Orbit Left Hand Circular Polarized Medium Earth Orbit Orthomode Transducer Passive Intermodulation Radio Frequency Return Loss Right Hand Circular Polarized Size, Weight and Power Transverse Electric Transverse Electric Magnetic Transmission Line Transverse Magnetic Waveguide Voltage Standing Wave Ratio
ID Code:993165
Deposited By: Mahmoud Gadelrab Ahmed Gadelrab
Deposited On:05 Jun 2024 15:18
Last Modified:05 Jun 2024 15:18

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