This paper presents the simulation and fabrication of a new power divider/combiner based on a new waveguide H-plane folded magic-T structure. Measurements of the fabricated magic-T confirm the accuracy of the optimization algorithms existing in the CST software (Genetic algorithm, Particle Swarm Optimization algorithm PSO, etc.). The magic-T structure exhibits moderate bandwidth response in the frequency range of 8-10 GHz. Also, it shows that the return loss is better than -15 dB, the insertion loss about -3.4 dB, and the isolation between the two output ports better than -25 dB in the frequency range of 8.4-10 GHz, with good transmission phase characteristics. Based on this magic-T structure, a 1:4 power divider/combiner is simulated and tested. The measured results show that the insertion loss is about -6.5±0.25 dB, the return loss less than -15 dB, the isolation among the output ports less than -25 dB, the combining efficiency about 89%, and the transmission phase differences are about ±2° in the frequency range of 8-10 GHz.
2. Shen, Z., C. L. Law, and C. Qian, "Hybrid finite-element-modal-expansion method for matched magic T-junction," IEEE Trans. Magn., Vol. 38, No. 2, 385-388, Mar. 2002.
3. Ritter, J. and F. Arndt, "Efficient FDTD/matrix-pencil method for the full-wave scattering parameter analysis of waveguiding structures," IEEE Trans. Microw. Theory Tech., Vol. 44, No. 12, 2450-2456, Dec. 1996.
4. San Blas, A. A., F. Mira, V. E. Boria, B. Gimeno, M. Bressan, and P. Arcioni, "On the fast and rigorous analysis of compensated waveguide junctions using off-centered partial-height metallic posts," IEEE Trans. Microw. Theory Tech., Vol. 55, No. 1, 168-175, Jan. 2007.
5. Robinson, J. and Y. Rahmat-Samii, "Particle swarm optimization in electromagnetic," IEEE Trans. Antennas Propag., Vol. 52, No. 2, 397-407, Feb. 2004.
6. Hwang, K. C., "Design and optimization of a broadband waveguide magic-T using a stepped conducting cone," IEEE Microwave and Wireless Components Letters, Vol. 19, No. 9, 539-541, Sep. 2009.
7. Russell, K. J., "Microwave power combining techniques," IEEE Trans. Microw. Theory Tech., Vol. 27, No. 5, 472-478, May 1979.
8. Chang, K. and C. Sun, "Millimeter-wave power-combining techniques," IEEE Trans. Microw. Theory Tech., Vol. 31, No. 2, 91-107, Feb. 1983.
9. Wu, H. C. and W. B. Dou, "A rigorous analysis and experimental researches of waveguide magic Tee at W-band," Progress In Electromagnetics Research, Vol. 60, 131-142, 2006.