1. Laverghetta, T. S., Practical Microware, Prentice-Hall, 1996.
2. Pozar, D. M., Microwave Engineering, John Wiley & Sons, Inc., 1998.
3. Betts, F., D. H. Temme, J. A. Weiss, and , "A switching circulator: S-band; Stripline; Remanent; 10KW; 10 Microsecond; Temperature-stable," G-MTT International Symposium Digest, Vol. 66, No. 1, 275-280, May 1966.
doi:10.1109/GMTT.1966.1122572 Google Scholar
4. Silber, L. M. and A. Weis, "A fast switching high power C-band ferrite circulator," IRE International Convention Record, Vol. 12, 32-36, Mar. 1964.
doi:10.1109/IRECON.1964.1147323 Google Scholar
5. Ayasli, Y., "Field effect transistor circulators ," Digests of Magnetics Conference, AC2, Mar. 1989.
doi:10.1109/INTMAG.1989.689920 Google Scholar
6. Ayasli, Y., "Field effect transistor circulators," IEEE Trans. Magnetics, Vol. 25, No. 5, 3242-3247, Sep. 1989.
doi:10.1109/20.42266 Google Scholar
7. Ayasli, Y. and U. S. Patent, "Non-ferrite non-reciprocal phase shifter and circulator,", No. 4801901.
doi:10.1109/20.42266 Google Scholar
8. Smith, M. A., "GaAs monolithic implementation of active circulators," Microwave Symposium Digest, Vol. 2, 1015-1016, May 1988. Google Scholar
9. Hara, S., T. Tokumitsu, and M. Aikawa, "Novel unilateral circuits for MMIC circulators," IEEE Trans. Microwave Theory Tech., Vol. 38, No. 10, 1399-1406, Oct. 1990.
doi:10.1109/22.58677 Google Scholar
10. Kother, D., B. Hopf, T. Sporkmann, I. Wolff, S. Kosslowski, and , "New types of MMIC circulators," Microwave and Millimeter-Wave Monolithic Circuits Symposium, 229-232, May 1995. Google Scholar
11. Berg, M., et al. "Active circulator MMIC in CPW technology using quarter micron InAlAs/InGaAs/InP in HFETs," Eighth International Conference on Indium Phosphide and Related Materials, 68-71, Apr. 1996. Google Scholar
12. Cryan, M. J. and P. S. Hall, "An integrated active circulator antenna," IEEE Microwave and Guided Wave Letters, Vol. 7, No. 7, 190-191, 1997.
doi:10.1109/75.594860 Google Scholar
13. Gupta, S., P. K. Nath, and B. K. Sarkar, "Integrated microstrip shorted antenna using hybrid active circulator," Asia-Pacific Microwave Conference, 719-722, Dec. 2000. Google Scholar
14. Kalialakis, C., M. J. Cryan, P. S. Hall, and P. Gardner, "Analysis and design of integrated active circulator antennas," IEEE Trans. Microwave Theory Tech., Vol. 48, No. 6, 1017-1023, Jun. 2000.
doi:10.1109/22.904739 Google Scholar
15. Miura, T., M. Kobayashi, and Y. Konishi, "Optimization of a lumped element circulator based on eigenvalue evaluation and structural improvement," IEEE Trans. Microwave Theory Tech., Vol. 44, No. 12, 2648-2654, Dec. 1996.
doi:10.1109/22.554616 Google Scholar
16. Fathy, Fathy, E. Denlinger, D. Kalokitis, V. Pendrick, H. Johnson, A. Pique, K. S. Harshavardhan, and E. Belohoubek, "Miniature circulators for microwave superconducting systems," IEEE MTTS International Microwave Symposium Digest, Vol. 1, 195-199, May 1995. Google Scholar
17. Denlinger, E., R. Paglione, D. Kalokitis, E. Belohoubek, A. Pique, X. D. Wu, T. Venkatesan, A. Fathy, V. Pendrick, S. Green, and S. Mathews, "Superconducting nonreciprocal devices for microwave systems," IEEE Microwave and Guided Wave Letters, Vol. 2, No. 11, 449-451, Nov. 1992.
doi:10.1109/75.165640 Google Scholar
18. Kadlec, J., "Tunable low-loss UHF circulator for cryogenic applications," IEEE Trans. Microwave Theory Tech., Vol. 82, No. 2, 173-176, Feb. 1982.
doi:10.1109/TMTT.1982.1131043 Google Scholar
19. Helszajn, J. and M. E. Powlesland, "Low-loss high-peak-power microstrip circulators," IEEE Trans. Microwave Theory Tech., Vol. 29, No. 6, 572-578, Jun. 1981.
doi:10.1109/TMTT.1981.1130395 Google Scholar
20. Miyoshi, T. and S. Miyauchi, "The design of planar circulators for wide-band operation," IEEE Trans. Microwave Theory Tech., Vol. 28, No. 3, 210-214, Mar. 1985.
doi:10.1109/TMTT.1980.1130042 Google Scholar
21. Okada, F. and K. Ohwi, "Design of a high-power CW Y-junction waveguide circulator," IEEE Trans. Microwave Theory Tech., Vol. 26, No. 5, 364-369, May 1978.
doi:10.1109/TMTT.1978.1129390 Google Scholar
22. Koning, J. G., Jr. R. J. Hamilton, and T. L. Hierl, "Full band low loss continuous tracking circulation in K-band," IEEE Trans. Microwave Theory Tech., Vol. 25, No. 2, 152-155, Feb. 1977.
doi:10.1109/TMTT.1977.1129058 Google Scholar
23. Okean, H. C. and L. J. Steffek, "Low loss, 3MM junction circulator," G-MTT International Microwave Symposium Digest, Vol. 73, No. 1, 80-82, Jun. 1973.
doi:10.1109/GMTT.1973.1123098 Google Scholar
24. Miura, T. and IEEE Trans. Magnetics, "An experimental high isolation ferrite substrate circulator magnetized by trigonally symmetric pole pieces,", Vol. 8, No. 3, 509-510, Sep. 1972. Google Scholar
25. Edrich, J. and R. West, "Very low loss L-band circulator with gallium substituted YIG," IEEE Trans. Magnetics, Vol. 5, No. 3, 481-482, Sep. 1969.
doi:10.1109/TMAG.1969.1066448 Google Scholar
26. Buehler, G. V. and A. F. Eikenberg, "A VHF high-power Y-circulator," IEEE Trans. Microwave Theory Tech., Vol. 9, No. 6, 569-v, Nov. 1961.
doi:10.1109/TMTT.1961.1125392 Google Scholar
27. Arams, F., B. Peyton, and B. Kaplan, "Octave-bandwidth UHF/L-band circulator," IEEE Trans. Microwave Theory Tech., Vol. 9, No. 3, 212-216, May 1961.
doi:10.1109/TMTT.1961.1125309 Google Scholar
28. Schloemann, E., "Miniature circulators," IEEE Trans. Magnetics, Vol. 25, No. 5, 3236-3241, Sep. 1989.
doi:10.1109/20.42265 Google Scholar
29. Katoh, H., "Temperature-stabilized 1.7-GHz broad-band lumped-lumpedelement," IEEE Trans. Microwave Theory Tech., Vol. 23, No. 8, 689-696, Aug. 1975.
doi:10.1109/TMTT.1975.1128649 Google Scholar
30. Brown, J. and J. Clark, "Miniaturized, temperature stable, coaxial Y-junction circulators," IEEE Trans. Microwave Theory Tech., Vol. 9, No. 3, 267-269, May 1961.
doi:10.1109/TMTT.1961.1125324 Google Scholar
31. Poirer, A. L., "An integrated microstrip circulator," IEEE Trans. Microwave Theory Tech., Vol. 19, No. 7, 661-662, Jul. 1971.
doi:10.1109/TMTT.1971.1127599 Google Scholar
32. Dunn, V. E. and R. W. Roberts, "New design techniques for miniature VHF circulators," G-MTT Symposium Digest, Vol. 65, No. 1, 147-152, May 1965.
doi:10.1109/GMTT.1965.1122495 Google Scholar
33. Chan, Y. K., B. K. Chung, and H. T. Chuah, "Transmitter and receiver design of an experimental airborne synthetic aperture radar sensor," Progress In Electromagnetic Research, Vol. 49, 203-218, 2004.
doi:10.2528/PIER04031601 Google Scholar
34. Chan, Y. K., "Transmitter and receiver design of an airborne synthetic aperture radar,", Master Dissertation, Multimedia, University, Malaysia, 2002. Google Scholar