Miniaturization of Power Divider and 90º Hybrid Directional Coupler for C-Band Applications Using Empty Substrate-Integrated Coaxial Lines

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] This paper presents the practical realization of a power divider and a 90° hybrid directional coupler in an empty substrate-integrated coaxial line (ESICL) for C-band frequency applications. This new type of transmission line is very promising in terms of electric performance, bandwidth, integration with other planar circuits, and manufacturing simplicity. The ESICL has been designed for obtaining a wide monomode bandwidth with a characteristic impedance of 50 . Furthermore, an improvement of the efficient transition between the ESICL and the grounded coplanar waveguide, used as feeding line, has been also proposed. The passive devices built using this technology are reduced in mass and volume, keeping robustness, and providing a well-balanced power division, as well as reduced losses and high isolation in the whole operational bandwidth. Two prototypes have been manufactured and the experimental results are in good agreement with the simulated designs.This work was supported in part by the Generalitat Valenciana Research under Project PROMETEOII/2015/005, in part by the Ministerio de Educacion, Cultura y Deporte, Spain, through the Fellowship Program for Training University Professors under Grant FPU14/00150, and in part by the Ministerio de Economia y Competitividad, Spain, through the Research and Development Projects under Grant TEC2016-75934-C4-1-R and Grant TEC2016-75934-C4-3-R.Merello-Gimenez, JM.; Nova-Giménez, V.; Bachiller Martin, MC.; Sánchez-Marín, JR.; Belenguer Martínez, Á.; Boria Esbert, VE. (2018). Miniaturization of Power Divider and 90º Hybrid Directional Coupler for C-Band Applications Using Empty Substrate-Integrated Coaxial Lines. IEEE Transactions on Microwave Theory and Techniques. 66(6):3055-3062. https://doi.org/10.1109/TMTT.2018.2828089S3055306266