Time-modulated array antennas – theory, techniques, and applications

ABSTRACT

This paper aims to present an up-to-date overview of the state-of-the-art about time-modulated arrays (TMAs). Starting from a description of the TMA fundamentals and basic theory in the time and frequency domain, the most popular techniques for synthesizing TMAs are revised. Afterwards, a survey of the main application contexts in which TMAs have been proposed is reported. Finally, current research trends are discussed and future developments envisaged.

KEYWORDS:

• Time-modulated arrays
• antenna beamforming
• multiple-beam antenna
• digital antenna
• radar
• MIMO communications

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

P. Rocca http://orcid.org/0000-0003-4522-6903

L. Poli http://orcid.org/0000-0002-8816-1970

S. Yang http://orcid.org/0000-0002-1546-8947

Notes

1. It is worth to point out that also amplifiers and phase shifters can be jointly used with the RF switches to introduce additional DoFs in the TMA synthesis. However, amplifiers and phase shifters are neglected in this work, unless specifically cited, to focus on the peculiar features of TMAs as compared to phased array antennas.

2. The sideband level is defined for the harmonic patterns (i.e. $h\ne 0$) as: $SB{L}^{\left(h\right)}=\underset{\theta }{max}|S{F}^{\left(h\right)}\left(\theta \right){|}^2/\underset{\theta }{max}|S{F}^{\left(0\right)}\left(\theta \right){|}^2$.

Additional information

Funding

This work benefited from the networking activities carried out within the project "CYBERPHYSICAL ELECTROMAGNETIC VISION: Context-Aware Electromagnetic Sensing and Smart Reaction (EMvisioning)" funded by the Italian Ministry of Education, University, and Research within the PRIN2017 Program, the SNATCH Project (2017-2019), funded by the Italian Ministry of Foreign Affairs and International Cooperation, Directorate General for Cultural and Economic Promotion and Innovation and the Project "Antenne al Plasma – Tecnologia abilitante per SATCOM (ASI.EPT.COM)" funded by the Italian Space Agency (ASI) under Grant 2018-3-HH.0 (CUP: F91I17000020005).

Notes on contributors

P. Rocca

P. Rocca the MS degree in Telecommunications Engineering from the University of Trento in 2005 (summa cum laude) and the PhD degree in Information and Communication Technologies from the same University in 2008. He is currently Associate Professor at the Department of Information Engineering and Computer Science (University of Trento) and a member of the ELEDIA Research Center. In April 2017, Prof. Rocca received the National Scientific Qualification for the position of Full Professor. Prof. Rocca is the author/co-author of 1 book chapter and of more than 120 journals and 250 conference papers. He has been a visiting PhD student at the Pennsylvania State University (USA), at the University Mediterranea of Reggio Calabria (Italy), and a visiting researcher at the Laboratoire des Signaux et Systèmes (L2S@ Supèlec, France) in 2012 and 2013. Moreover, he has been an Invited Professor at the University of Paris Sud (France) in 2015 and at the University of Rennes 1 (France) in 2017. Prof. Rocca has been awarded from the IEEE Geoscience and Remote Sensing Society and the Italy Section with the best PhD thesis award IEEE-GRS Central Italy Chapter. His main interests are in the framework of artificial intelligence (optimization and machine learning) techniques as applied to electromagnetics, antenna array synthesis and design, and electromagnetic inverse scattering. He served as an Associate Editor of the IEEE Antennas and Wireless Propagation Letters in the period 2011–2016 and is an Associate Editor of the Microwave and Optical Technology Letters.

F. Yang

F. Yang was born in Chongqing Province, China, in 1991. He received the BS degree in electronic science and technology from Chongqing University of post and telecommunications, Chongqing, China, in 2014. He is currently working toward the PhD degree in electromagnetics and microwave.

L. Poli

L. Poli received the MS degrees in Telecommunication Engineering from the University of Trento, Italy, in 2008, and the PhD degree from the International Doctoral School in Information and Communication Technology in 2012. He is a member of the ELEDIA Research Center. His research activities are focused on the solution of antenna array synthesis and electromagnetic inverse scattering problems.

S. Yang

S. Yang was born in Sichuan Province, China, in 1967. He received the BS degree in electronic science and technology from East China Normal University, Shanghai, and the MS degree in electromagnetics and microwave technology and the PhD degree in physical electronics from the University of Electronic Science and Technology of China (UESTC), Chengdu, in 1989, 1992 and 1998, respectively. From 1994 to 1998, he was a Lecturer with the Institute of High Energy Electronics, UESTC. From 1998 to 2001, he was a Research Fellow at the School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore. From 2002 to 2005, he was a Research Scientist with Temasek Laboratories, National University of Singapore. Since 2005, he has been a Full Professor with the School of Electronic Engineering, UESTC. Since 2015, he has been a Chang-Jiang Professor nominated by the Ministry of Education of China. He has authored or co-authored over 200 technical papers. His current research interests include antennas, antennas arrays, optimization techniques, and computational electromagnetics. Prof. Yang received the Foundation for China Distinguished Young Investigator presented by the National Science Foundation of China in 2011. He is the chair of the IEEE AP-S/EMC-S Joint Chengdu Chapter and serves as an Editorial Board Member of IJAP and Chinese Journal of Electronics.