Novel multifunctional six-port network based on substrate integrated waveguide (SIW) magic-T

A novel multifunctional six-port network based on SIW magic-T is presented in this paper. The six-port network not only realizes the function of four-way power division or combination with high isolation but also has the function of magic T. Differing from conventional power dividers, this six-port network is capable of both in-phase and out-of-phase power division. Furthermore, the isolation effect of the six-port network is achieved through a combination of magic-T isolation and resistive isolation, thus reducing the number of resistors used. Equivalent circuit models are developed and used for in-depth analysis of this network. The multifunctional six-port network is designed and fabricated. Measured results show that the circuit achieves an input return loss greater than 15 dB and an insertion loss of 6.9 dB. In addition, the circuit achieves an isolation of greater than 20 dB between the opposite-side ports and greater than 15 dB between the same-side ports.