In this letter, a compact spiral element is proposed for wideband beam-steering arrays. The extremely limited element spacing and size to prevent the occurrence of grating lobes at high frequency range are the most critical issues in designing wideband phased arrays. Two miniaturization techniques are simultaneously applied to an Archimedean spiral radiator to reduce the area of the proposed spiral. This spiral radiator is designed with a reflector plane instead of an absorber and cavity to realize low-profile characteristics and achieve unidirectional pattern without power loss. A wideband balun that operates simultaneously as a wideband impedance transformer is also miniaturized to be integrated between the radiator and reflector plane. The proposed element consists of these three components, and its size is 0.25 λL × 0.25 λL × 0.13 λL, where λL is the wavelength at 2 GHz, the lowest frequency of interest. This compact spiral element with a simple structure and design procedure can achieve wideband beam steering without grating lobes and be employed in numerous applications, such as conformal arrays.
Bibliographical noteFunding Information:
Manuscript received October 12, 2016; revised November 27, 2016 and December 7, 2016; accepted December 28, 2016. Date of publication April 12, 2017; date of current version July 24, 2017. This work was supported by the Electronic Warfare Research Center at Gwangju Institute of Science and Technology, originally funded in part by the Defense Acquisition Program Administration and in part by Agency for Defense Development. (Corresponding author: Young Joong Yoon.) The authors are with the Department of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, South Korea (e-mail: ahnjihwan@ yonsei.ac.kr; email@example.com; firstname.lastname@example.org; yjyoon@yonsei. ac.kr).
© 2017 IEEE.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering