Present paper describes the design, development and evaluation of a wideband, compact Ku-band orthomode transducer (OMT) for SATCOM application. It consists of a square waveguide output section, square waveguide to rectangular waveguide transition, straight waveguide port and an orthogonally coupled port. A tapered waveguide section has been used to couple the orthogonal RF (Radio Frequency) signal to the common port. The designed OMT has a transmit port with frequency band 13.75 GHz-14.5 GHz and a receive port with frequency band 10.95-12.5 GHz. Finite element method based ANSYS's High Frequency Structure Simulator (HFSS) EM software has been used for simulation and optimization of OMT. Measured reflection coefficients of OMT over transmission and reception frequency bands are better than -15 dB and -12 dB, respectively. Designed OMT has port to port isolation better than 45 dB against 30 dB isolation of conventional OMT available in market.
2. Dang, N. D., S. Kapartis, and D. J. Brain, "A wideband compact end-entry septum polariser OMT," Int. Conference on Antenna & Propagation ICAP87, Vol. 1, No. 274, 419-423, U.K., 1987.
3. Skinner, S. J. and G. L. James, "Wideband ortho-mode transducer," IEEE Trans. Microwave Theory & Tech., Vol. 39, No. 2, 294-300, February 1991.
4. Uher, J., J. Bornemann, and U. Rosenberg, Waveguide Components for Antenna Feed Systems: Theory and CAD, Artech House, Norwood, MA, 1993.
5. Rebollar, J. M., J. Esteban, and J. de Frutos, "A dual frequency OMT in the Ku band for TT&C applications," IEEE Antennas and Propagation Society International Symposium, Vol. 4, 2258-2261, Atlanta, GA, June 1998.
6. Targonski, S. D., "A multiband antenna for satellite communications on the move," IEEE Trans. Antennas Propag., Vol. 54, No. 10, 2862-2868, October 2006.
7. Sharma, S. B., V. K. Singh, and S. Chakrabarty, "Multifrequency waveguide ortomode transducer," IEEE Trans. Microwave Theory & Tech., Vol. 53, No. 8, 2604-2609, August 2005.
8. Tao, Y. and Z. Shen, "Broadband substrate integrated waveguide orthomode transducers," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 16, 2099-2108, 2009.
9. Soon, M. H., S. Choi, J. M. Kim, and B. Song, "Design of an orthomode transducer for use in multi-band antenna feeds," PIERS Proceedings, 1172-1176, Moscow, Russia, August 18–21, 2009.
10. Tao, Y., Z. Shen, and G. Liu, "Dual-band ortho-mode transducers with irregularly shaped diaphragm," Progress In Electromagnetics Research Letters, Vol. 27, 1-8, 2011.
11. Dunning, A., M. Bowen, and Y. Chung, "Offset quad ridged ortho-mode transducer with a 3.4 : 1 bandwidth," 2013 Asia-Pacific Microwave Conference Proceedings (APMC), Vol. 146, No. 148, 2013.
12. Fan, J., Y. Yan, C. Jin, D. Zhan, and J.-R. Luo, "Design of wideband quad-ridged waveguide orthomode transducer at L-band," Progress In Electromagnetics Research C, Vol. 72, 115-122, 2017.
13. Boifot, A. M., E. Lier, and T. Schaug-Pettersen, "Simple and broadband orthomode transducer," IEE Proceedings Microwaves, Antenna & Propagation, Vol. 137, No. 6, 396-400, 1990.
14. Boifot, A. M., "Classification of orthomode transducer," European Trans on Emerging Telecommunication Technologies, Vol. 2, No. 5, 503-510, 1991.