Three-Dimensional Low-Loss Power-Dividing Networks Based on Metal Integrated Suspended Line (MISL) for High Power Applications

In this article, the transmission characteristics of metal integrated suspended line (MISL) technology are studied which is verified by the thru-reflect-line (TRL) de-embedding method. In addition, practical design guidelines for MISL circuits are provided. A 3-D T-junction power-dividing network is introduced. Furthermore, a 3-D Gysel power-dividing network is designed based on the proposed T-junction power-dividing network. Both networks exhibit low-loss performance. They also have a higher power handling capability (PHC) than traditional printed circuit board (PCB). In contrast to waveguide circuits, they utilize multilayer metal stacking, have the characteristics of quasi-planar circuits, and reduce the manufacturing cost. Moreover, compared with the substrate-integrated suspended line (SISL) circuits, the MISL technology reduces the number of circuit layers by combining computer numerical control (CNC) machining with laser and etching technologies, simplifying assembly processes.