A High Gain Multi-Port Series Fed Array Realized with Micromachined Low-Cost 3D-Printed Substrate

Abstract

A low-cost three-port series-fed antenna array with pattern diversity for WLAN applications is presented. The three antennas resonate at 5.8 GHz with 12 dBi antenna gain. The antenna substrate consists of an air cavity within the substrate, which is introduced to enhance the gain and radiation efficiency. The principle of micromachining was used to realize the substrate characteristic that lowers the dielectric constant, compared to a conventional non-micromachined substrate. The antenna uses scaled parasitic patches as a superstrate to improve and equalize the gain of the respective antennas when the antenna beam scans through +18⁰, 0⁰, and −18⁰. The parasitic patches as a superstrate were found to have low scanning loss when the antenna beam is tilted from the broadside. The proposed superstrate design enhances the gain at the broadside and oblique radiations making the design more versatile as the gain enhancement becomes invariant to the incidence angle. The planar superstrate enhances the gains of three antennas with 2.4, 2.8, and 7.1 dB so that the final antenna gain is equalized to 12 dBi at the three ports. To validate the design, the antenna module is fabricated on the polylactic acid (PLA) substrate using the industry-standard photolithography process.

KEYWORDS:

• Gain enhancement
• WLAN
• Three-port antenna
• Series-fed antenna array
• Pattern diversity
• Three-dimensional (3-D) printing

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Swapna S

Swapna S received her undergraduate degree in electronics and communication engineering from the University of Kerala in the year 2011 and master’s degree in VLSI design and embedded systems from National Institute of Technology Rourkela, Odisha in 2013. She is currently pursuing her PhD from Centre for Applied Research in Electronics, Indian Institute of Technology Delhi. Her research interests include pattern diversity antennas, additive manufacturing antennas and metamaterials.

Karthikeya G S

Karthikeya G S (Senior Member, IEEE) received his undergraduate degree in electronics and communication engineering, with distinction, in the year 2010 from Visvesvaraya Technological University, Belgaum. He received his master's degree, with distinction, in microwave engineering from University of Kerala in 2012. He worked as an assistant professor in affiliated colleges of Visvesvaraya technological university from 2013 to 2016, where he established the Antenna Architects' lab. He joined the Centre for applied Research in Electronics (CARE), IIT Delhi as a PhD student in 2017 and defended his thesis in 2019. He worked as a project scientist at Foundation for Innovation and Technology Transfer (FITT) in association with Synergy Microwave Corporation from 2019 to 2021. From 2021 to 2022 he served as an assistant professor at the Centre for Antennas and Radio Frequency Systems (CARFS), Ramaiah Institute of Technology. Since 2023, he is serving as an assistant professor at the Advanced RF and Wireless Communication Lab, Department of Electronics and Communication, BMS College of Engineering. He has authored or co-authored more than 70 articles in peer-reviewed journals and international conference proceedings. He has also filed six Indian patents and two US patents. He has co-authored three state-of-the art books and a book chapter. He also holds a copyright on 5G antenna module design. One of his articles was featured as a cover page feature in Microwave Journal, an industry leading magazine. His research interests include multi-octave antenna systems for portable devices, novel material design for antenna applications, mm Wave antennas for mobile terminals and base stations. He serves as a research consultant to Meander Spectra Pvt Ltd and Antsys Innovation Pvt Ltd. He is a senior member of IEEE-Antenna Propagation Society and a life member of Antenna Test and Measurement society. He serves as a reviewer of several IEEE and JohnWiley journals. He is a recipient of Dr N Vasudevan Nair Memorial Award (2011) and Research Excellence Travel Award (2019). Email: [email protected]

Shiban K Koul

Shiban K Koul received the BE degree in electrical engineering from the Regional Engineering College, Srinagar, India, in 1977, and the MTech and PhD degrees in microwave engineering from the Indian Institute of Technology Delhi, New Delhi, India, in 1979 and 1983, respectively. He is currently an emeritus professor at the Indian Institute of Technology, Delhi. He served as deputy director (Strategy and Planning) at IIT Delhi from 2012–2016 and mentor deputy director (Strategy & Planning, International Affairs) at IIT, Jammu from 2018–2020. He also served as the chairman of Astra Microwave Products Limited, Hyderabad from 2009–2019 and Dr R P Shenoy Astra Microwave chair professor at IIT Delhi from 2014–2019. His research interests include: RF MEMS, high frequency wireless communication, microwave engineering, microwave passive and active circuits, device modelling, millimeter wave IC design and reconfigurable microwave circuits including antennas. He has successfully completed 38 major sponsored projects, 52 consultancy projects and 60 technology development projects. He has authored/co-authored 450 papers, 11 state-of-the art books and 3 book chapters. He holds 13 patents and 6 copyrights. Prof Koul is a Life Fellow of the IEEE, USA, fellow of the Indian National Academy of Engineering, India, and Institution of Electronics and Telecommunication Engineers (IETE), India. He is the chief editor of IETE Journal of Research and associate editor of the International Journal of Microwave and Wireless Technologies, Cambridge University Press. He served as a distinguished microwave lecturer of IEEE MTT-S for the period 2012–2014. He also served as an AdCom member of the IEEE MTT-S from 2010–2018 and is presently a member of the Awards, Nomination and Appointments, MGA, M&S and Education committees of the IEEE MTT-S. Dr. Koul is recipient of numerous awards including IEEE MTT Society Distinguished Educator Award (2014); Teaching Excellence Award (2012) from IIT Delhi; Indian National Science Academy (INSA) Young Scientist Award (1986); Top Invention Award (1991) of the National Research Development Council for his contributions to the indigenous development of ferrite phase shifter technology; VASVIK Award (1994) for the development of Ka-band components and phase shifters; Ram Lal Wadhwa GoldMedal (1995) IETE; Academic Excellence Award (1998) from Indian Government for his pioneering contributions to phase control modules for Rajendra Radar, Shri Om Prakash Bhasin Award (2009) in the field of Electronics and Information Technology, VASVIK Award (2012) for the contributions made to the area of information, communication technology (ICT) and M N Saha Memorial Award (2013) from IETE. Email: [email protected]

Ananjan Basu

Ananjan Basu received the BTech degree in electrical engineering and MTech degree in communication and radar engineering from the Indian Institute of Technology Delhi (IIT, Delhi), in 1991 and 1993 respectively, and the PhD degree in electrical engineering from University of California at Los Angeles (UCLA), in 1998. He has been with the Centre for Applied Research in Electronics, IIT, Delhi as an assistant professor (2000–2005) and associate professor (2005–2012), and professor (2013 onwards). His specialization is in microwave and millimetrewave component design and characterization, reconfigurable and active antennas, microwave imaging and guided wave theory. Email: [email protected]