This paper presents the design of a tri-mode matched feed horn to remove the beam squinting effects in a circularly polarized offset parabolic reflector antenna. In a conical horn, three modes i.e., TE11, TM11 and TE21 are combined in proper amplitude and phase proportion to obtain a tri-mode matched feed configuration. The proposed tri-mode horn is then used as a primary feed device to illuminate the circularly polarized offset parabolic reflector antenna. The simulated data on radiation characteristics of the offset reflector are used to estimate the magnitude of beam squinting and the results are compared with that of a conventional potter horn fed offset reflector. The experimental results on secondary radiation pattern are also incorporated in the paper.
Dhaval A. Pujara,
Soumyabrata B. Chakrabarty,
Vijay Kumar Singh,
"Removal of Beam Squinting Effects in a Circularly Polarized Offset Parabolic Reflector Antenna Using a Matched Feed," Progress In Electromagnetics Research Letters,
Vol. 7, 105-114, 2009. doi:10.2528/PIERL08122402
1. Chu , T.-S. and R. H. Turrin, "Depolarization properties of offset reflector antennas," IEEE Trans. on Antennas and Propagation, Vol. 21, 339-345, 1973. doi:10.1109/TAP.1973.1140479
2. Jacobsen, J., "On the cross polarization of asymmetric reflector antenna for satellite applications," IEEE Trans. on Antennas and Propagation, 276-283, 1977. doi:10.1109/TAP.1977.1141565
3. Adatia, N. A. and A. W. Rudge, "Offset-parabolic reflector antennas: A review," Proc. of IEEE, Vol. 66, 1592-1618, 1978. doi:10.1109/PROC.1978.11170
4. Adatia, N. A. and A. W. Rudge, "Beam squint in circularly polarised offset — Reflector antenna," Electronics Letters, Vol. 11, 513-515, 1975. doi:10.1049/el:19750396
5. Fiebig, D., R. Wohlleben, A. Prata, and W. V. T. Rusch, "Beam squint in axially symmetric reflector antennas with laterally displaced feeds," IEEE Trans. on Antennas and Propagation, Vol. 39, 774-779, 1991. doi:10.1109/8.86875
6. Adatia, N. A. and A. W. Rudge, "New class of primaryfeed antennas for use with offset parabolic reflector antennas," Electronics Letters, Vol. 11, 597-599, 1975. doi:10.1049/el:19750396
7. Prasad, K. M. and L. Shafai, "Improving the symmetry of radiation patterns for offset reflectors illuminated by matched feeds," IEEE Trans. on Antennas and Propagation, Vol. 36, 141-144, 1988. doi:10.1109/8.1086
8. Bahadori, K. and Y. Rahmat-Samii, "A tri-mode horn feed for gravitationally balanced back-to-back reflector antennas," IEEE Trans. on Antennas and Propagation, Vol. 55, No. 10, 2654-2661, 2007. doi:10.1109/TAP.2007.905835
9. Sharma, S. B., D. A. Pujara, S. B. Chakrabarty, and V. K. Singh, "Performance comparison of a matched feed horn with a potter feed horn for an offset parabolic reflector," IEEE Antennas and Propagation Society International Symposium, San Diego, 2008.
10. Potter, P. D., "A new horn antenna with suppressed side lobes and equal beamwidth," Microwave Journal, Vol. 6, 71-78, 1963.
11. Silver, S., Microwave Antenna Theory and Design, 336-338, McGraw-Hill, New York, 1949.
12. Watson, B. K., A. W. Rudge, and N. A. Adatia, "Dual-polarized mode generator for cross-polar compensation in parabolic reflector antennas," 8th European Microwave Conference, 183-187, Paris, 1978. doi:10.1109/EUMA.1978.332532
13. Pontoppidan, K., "GRASP-technical description,", TICRA Engineering Consultants, Denmark..