一种基于 SICL 的混合环设计与实现

In this paper, an L-band hybrid ring based on the substrate integrated coaxial line (SICL) is designed, which can be used in monopulse radar system. SICL has the characteristics of high efficiency, colorless dispersion and single working mode. It is a transmission line form with important applications. Taking SICL as the transmission line, a hybrid ring structure with two-layer dielectric substrate is designed, and conductive through holes are used to realize the interconnection of upper and lower metal planes. At the output end, in order to facilitate coaxial feeding, a transfer structure from microstrip line to SICL is designed. The conductive through hole is used to realize the vertical connection between microstrip line and the conductor in SICL, so as to achieve better impedance matching. Based on the above working principle, a hybrid ring operating at 1~1.2 GHz is designed. The simulation results show that the voltage standing wave ratio (VSWR) of each port is less than 2 and the port isolation is more than 20 dB. The function of sum and difference is realized. The processing and test results show the effectiveness of the scheme designed in this paper. The hybrid ring structure based on SICL has the advantages of simple design, easy processing and good electromagnetic compatibility, which can be applied in engineering.