Increasing the Gain of Beam-Tilted Circularly Polarized Radial Line Slot Array Antennas

Koli, MNY; Afzal, MU; Esselle, KP

Increasing the Gain of Beam-Tilted Circularly Polarized Radial Line Slot Array Antennas

Koli, MNY Afzal, MU Esselle, KP

Permalink

Publisher:: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Publication Type:: Journal Article
Citation:: IEEE Transactions on Antennas and Propagation, 2022, 70, (6), pp. 4392-4403
Issue Date:: 2022-06-01

Closed Access

	Filename	Description	Size
	Increasing_the_Gain_of_Beam-Tilted_Circularly_Polarized_Radial_Line_Slot_Array_Antennas.pdf	Published version	9.42 MB	Adobe PDF	View/Open

Copyright Clearance Process

Recently Added
In Progress
Closed Access

This item is closed access and not available.

Full metadata record

Field	Value	Language
dc.contributor.author	Koli, MNY
dc.contributor.author	Afzal, MU
dc.contributor.author	Esselle, KP
dc.date.accessioned	2023-04-06T03:27:51Z
dc.date.available	2023-04-06T03:27:51Z
dc.date.issued	2022-06-01
dc.identifier.citation	IEEE Transactions on Antennas and Propagation, 2022, 70, (6), pp. 4392-4403
dc.identifier.issn	0018-926X
dc.identifier.issn	1558-2221
dc.identifier.uri	http://hdl.handle.net/10453/169293
dc.description.abstract	This article presents a new type of beam-tilted circularly polarized (CP) radial line slot array (RLSA) antennas. When the conventional beam tilting method is applied to CP-RLSA antennas, the aperture efficiency of the antenna degrades significantly due to very sparse slots in some parts of the antenna. A new method is presented to prevent this, and hence a much higher gain and aperture efficiency are achieved from the same antenna area. The key to the new method is an aggressively biased truncation of the slot layout that leaves out sparse slots. Consequently, the feed point moves closer to an edge of the TEM waveguide. A reflecting wall is introduced to prevent leakage from this edge. It is shown that the gain of RLSAs with beams tilted to 25° and 45° (measured from normal direction) can be increased by 5.5 dB (from 20.5 to 26 dBic) using the new method as opposed to the conventional method. The new concept and predicted results are validated using a prototype antenna with the beam-tilted to an angle of 25°. The aperture diameter and overall thickness of the prototype are 12λ0 and 0.4λ0, respectively, where λ0 is the free-space wavelength at the operating frequency of 18 GHz. The measured results confirmed a higher gain of 26.2 dBic, an aperture efficiency of 30%, the overall efficiency of 93.2%, and sidelobe levels (SLLs) less than -25 dB at 18 GHz. The measured 10 dB return loss bandwidth of the antenna is greater than 63.7%, 3 dB axial-ratio bandwidth is 13.3%, and 3 dB gain bandwidth is 6.7%.
dc.language	English
dc.publisher	IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
dc.relation.ispartof	IEEE Transactions on Antennas and Propagation
dc.relation.isbasedon	10.1109/TAP.2022.3140490
dc.rights	info:eu-repo/semantics/closedAccess
dc.subject	0906 Electrical and Electronic Engineering, 1005 Communications Technologies
dc.subject.classification	Networking & Telecommunications
dc.title	Increasing the Gain of Beam-Tilted Circularly Polarized Radial Line Slot Array Antennas
dc.type	Journal Article
utslib.citation.volume	70
utslib.for	0906 Electrical and Electronic Engineering
utslib.for	1005 Communications Technologies
pubs.organisational-group	/University of Technology Sydney
pubs.organisational-group	/University of Technology Sydney/Faculty of Engineering and Information Technology
pubs.organisational-group	/University of Technology Sydney/Faculty of Engineering and Information Technology/School of Electrical and Data Engineering
utslib.copyright.status	closed_access	*
dc.date.updated	2023-04-06T03:27:49Z
pubs.issue	6
pubs.publication-status	Published
pubs.volume	70
utslib.citation.issue	6

Abstract:

This article presents a new type of beam-tilted circularly polarized (CP) radial line slot array (RLSA) antennas. When the conventional beam tilting method is applied to CP-RLSA antennas, the aperture efficiency of the antenna degrades significantly due to very sparse slots in some parts of the antenna. A new method is presented to prevent this, and hence a much higher gain and aperture efficiency are achieved from the same antenna area. The key to the new method is an aggressively biased truncation of the slot layout that leaves out sparse slots. Consequently, the feed point moves closer to an edge of the TEM waveguide. A reflecting wall is introduced to prevent leakage from this edge. It is shown that the gain of RLSAs with beams tilted to 25° and 45° (measured from normal direction) can be increased by 5.5 dB (from 20.5 to 26 dBic) using the new method as opposed to the conventional method. The new concept and predicted results are validated using a prototype antenna with the beam-tilted to an angle of 25°. The aperture diameter and overall thickness of the prototype are 12λ0 and 0.4λ0, respectively, where λ0 is the free-space wavelength at the operating frequency of 18 GHz. The measured results confirmed a higher gain of 26.2 dBic, an aperture efficiency of 30%, the overall efficiency of 93.2%, and sidelobe levels (SLLs) less than -25 dB at 18 GHz. The measured 10 dB return loss bandwidth of the antenna is greater than 63.7%, 3 dB axial-ratio bandwidth is 13.3%, and 3 dB gain bandwidth is 6.7%.

Please use this identifier to cite or link to this item:

http://hdl.handle.net/10453/169293