Symmetrically Direct Coupled Stacked Broadband Microstrip Antenna

ABSTRACT

A technique employing the use of directly coupled stacked patches to increase impedance bandwidth with reduced cross-polarization is proposed in this paper. The top stacked multi-resonator configurations are directly excited by employing metallic shorting posts (vias) between the metallic patches. In stacked directly coupled MSA, a bandwidth of 25.8% and a gain of 8.8 dBi with a gain variation of ±0.2 dB over the band are achieved. The cross-polar levels for this configuration are less than −15 dB and −5 dB at lower and upper frequencies, respectively. To suppress the cross-polar components, a symmetrically direct-coupled stacked MSA design is proposed. In this configuration, a bandwidth of 26.1% and a gain of 9.3 dBi with ±0.3 dB variation over the entire bandwidth are achieved. The cross-polar levels are significantly suppressed up to −25 dB and −16 dB at lower and upper frequencies, respectively. The proposed antenna configurations are designed and fabricated. The experimental results agree with the simulated results.

KEYWORDS:

• Antenna feeds
• Broadband antennas
• Microstrip antennas
• Patch antennas

Additional information

Notes on contributors

Bindu K. K

Bindu K K received BTech in electronics and communication from Government Engineering College, Kottayam, Kerala, India, in 1996. Currently, she is pursuing PhD degree from Indian Institute of Technology, Bombay. She joined the Department of Electronics and Communication Engineering at Government Engineering College, Thrissur, India, in December 1996, and College of Engineering, Trivandrum, India, in August 1997, as lecturer. Since April 2000, she has been contributing towards the design and development of RF and digital sub-systems for active phased array radars at Electronics & Radar Development Establishment, DRDO, India. E-mail: [email protected]

Rajbala S

Rajbala S received BTech in electronics and communication from PDPM Indian Institute of Information Technology, Design and Manufacturing Jabalpur, Madhya Pradesh, India, in 2012. She received MTech in electrical engineering with specialization in communication and signal processing from Indian Institute of Technology, Bombay, India, in 2016. She worked on compact and broadband antennas for her MTech project. Currently, she is a research scholar at Indian Institute of Technology, Bombay.

Girish Kumar

Girish Kumar received PhD degree in electrical engineering from IIT Kanpur in 1983. From 1983 to 1985, he was a research associate in the Electrical Engineering Department, University of Manitoba, Winnipeg, Canada. From 1985 to 1991, he was an assistant professor in the Electrical Engineering Department, University of North Dakota, Grand Forks, USA. Since 1991, he is at IIT Bombay, where he is currently a professor in the Electrical Engineering Department. His areas of interest are antennas, microwave circuits and systems. He has written more than 300 papers in the international and national journals and conference proceedings. He is author of four books and has filed nine patents. He was the chairman of the company “Wilcom Technologies Pvt. Ltd”, an IIT Bombay incubated company. Wilcom had developed several products, such as mobile phone jammers, signal enhancers, radiation shield, antennas, power dividers, couplers, filters, amplifiers, etc. E-mail: [email protected]

Anil K. Singh

Anil Kumar Singh obtained his PhD in 1990 in electronics engineering, IT-BHU. He joined Electronics and Radar Development Establishment (LRDE), DRDO in November 1991 as Scientist C and was promoted to the rank of Outstanding Scientist in 2015. He worked in LRDE/DRDO till 5 March 2017 in various capacities like core designer, project manager, divisional head, project director, and associate director of the lab. As a chief designer and project director, he established various radar antenna technologies such as slotted waveguide array antennas, microstrip array antennas, multi beam antennas, passive phased array systems, and active phased array systems with DBF indigenously, thereby leading successful development and product ionization of various types of military radars for defence forces.

Singh took over charge of director, Defence Electronics Research Laboratory (DLRL)/DRDO, 6 March 2017. He led the laboratory towards development of state of the art next-generation high performance integrated electronic warfare systems for various platforms for Indian armed forces, Paramilitary forces, and home land security.

Singh has authored more than 150 research papers in different international/national journals and symposiums. He has 3 copyrights and 10 patents to his credit. For his novel invention and significant contributions, he has been awarded NRDC (National Research Development Corporation) meritorious invention award 1997, DRDO National Science Day commendation 2005, DRDO Technology Group Award 2006, DRDO award for performance excellence 2008, IETE-IRSI award 2009, DRDO Agni award of excellence in self reliance 2011, and IETE-CDIL award 2014. He is the fellow of IETE. E-mail: [email protected]