Higher Order Mode Analysis of Dual-Post Discontinuity in a Circular Waveguide

ABSTRACT

This paper presents the analysis of scattering characteristics of two radially directed posts in an oversized circular waveguide making an arbitrary angle in the transverse plane using method of moments. Electric-type dyadic Green's function has been used to compute the scattered field in a circular waveguide. Simulated data on return loss and power coupling in the dominant mode and higher order modes have been compared with the data computed using Ansoft HFSS. The data on return loss for the incident TE₁₁ mode have been compared with experimental data for the circular waveguide loaded with two posts.

KEYWORDS:

• Circular waveguide
• Green's function
• higher order modes
• post discontinuity

Acknowledgements

The authors would like to thank Shri Tapan Misra, Director SAC, Ahmedabad and Dr K. S. Dasgupta, Director IIST, Trivandrum for their encouragement and support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Ranajit Dey

Ranajit Dey was born in Kolkata, India in 1981. He graduated in electronics and telecommunication engineering from Kalyani University, Kalyani in 2003 and he received the ME degree from Jadavpur University in electronics and telecommunication engineering with specialization in microwave engineering in 2005. Presently, he is working in Space Applications Centre, ISRO. His present areas of research are computational electromagnetics and space-borne antenna design. Currently, he is pursuing his PhD from Indian Institute of Space Science and Technology, Trivandrum, India.

E-mail: [email protected]

S.B Chakrabarty

Soumyabrata Chakrabarty was born on 3 January 1966 in Karimganj district of Assam. He received the BE (Hons) degree from Gauhati University in 1988, the ME degree from Jadavpur University in the year 1992 both in electronics and telecommunication engineering, and the PhD degree in engineering from Indian Institute of Technology, Kharagpur in the year 1996. He is currently working in antenna systems area, Space Applications Centre, Ahmedabad as senior scientist/engineer and divisional head, Microwave Sensors Antenna Division. He is involved in the development of antennas related to microwave remote sensing and his areas of interest are computational electromagnetics, microwave, and millimeter-wave antennas.

E-mail: [email protected]

Rajeev Jyoti

Rajeev Jyoti received the MSc degree from Delhi University in 1984 and the MTech degree from Delhi University in 1986. He has an experience of more than 20 years in the design, analysis, and development of microwave antennas systems required in Space Applications Centre (SAC), Ahmedabad for ground- and space-borne antennas for communication and remote sensing satellites. He has been at ESTEC, European Space Agency (ESA), The Netherland for 14 months as UN fellow on antenna and propagation. He has developed antenna systems for Indian Satellite INSAT 4A/4B/4C & RISAT, GSAT series of satellite namely Education satellite, GSAT1, GSAT2, GSAT4. He has developed antenna technologies for earth station antenna system for building INSAT-based ground antenna systems.

E-mail: [email protected]

Thomas Kurian

Thomas Kurian received the MTech degree from IIT Kanpur in 1976 and subsequently joined ISRO in 1977. He also received the PhD degree from University of Kerala, in 2004. He has expertise in design and development of control electronics for stabilization of a magnetic field for particle accelerator using NMR and he worked on test and evaluation of the satellite systems. Developed a microprocessor-based simulator for in orbit simulation of the solar panel output at different aspect angles of SEO satellite to calculate the energy balance of the battery. He participated in the SEO II launch at Cosmodrome and underwent training at DFVLR, Germany for test and evaluation of MEOSS payload for SROSS satellite.

E-mail: [email protected]