## 4 Conclusions  
RF-MEMS, i.e., Microsystems (MEMS) based Radio Frequency passive components, exhibit pronounced characteristics in terms of high performance, tunability/reconfigurability, and frequency agility, making them an interesting solution for the upcoming fifth generation of mobile communications, i.e., 5G, with all its implications and spillovers in the Internet of Things (IoT). Active development of 5G technologies and satellite communication demands for high-speed stable data transfer services from any location. Satellite systems providing high-speed Internet connectivity utilize K and Ka frequency bands offering a larger bandwidth compared to lower frequencies bands.  
This work presented and discussed a couple of design concepts of RF-MEMS-based reconfigurable phase shifters working in the K and Ka bands, with 19.5 GHz and 29.3 GHz center frequency, respectively. Both networks feature 4 reconfigurable stages and realize 16 different phase delays by means on series ohmic RF-MEMS switches. In particular, the phase shifter design concept working in the Ka band employs a novel in-line switch solution, which allows conjugating the compactness of cantilevered micro-relays with the robustness of the clamped-clamped configuration.  
The characteristics and performance of the RF-MEMS phase shifters and standalone switches were extensively discussed, capitalizing on Finite Element Method (FEM) simulations and experimental testing of the S-parameters.  
Due to a technology-related non-ideality, the ON-state resistance of the switches was larger than the nominal value. This led to losses around 0.8-0.9 dB at K and Ka center frequencies, while the simulations predicted 0.1-0.2 dB. As the discussed phase shifters, regardless of the selected configuration, always employ eight cascaded ON switches, the impact on the overall RF characteristics is important. The measured networks exhibited additional losses (S21) as large as 5-7 dB at the two center frequencies when compared to FEM simulations. However, the reason for such a scarce performance is known and identified at the technology level, and the next fabricated samples will show better performance. Finally, despite the large divergence from the nominal specifications, the measured phase shift configurations exhibited limited differences when compared to simulations.  
Figure 12: The phase difference between simulations and measurements at the center frequencies for the (**a**) K band and (**b**) Ka band RF-MEMS phase shifters.  
**Author Contributions:** Conceptualization, E.S.; data curation, J.I. and E.B.; funding acquisition, E.S.; investigation, G.R., A.B., F.G., E.B., R.K., A.T., and M.D.; methodology, J.I., E.S., R.K., and A.T.; supervision, J.I.; validation, E.B.; visualization, J.I.; writing--original draft, J.I.; writing--review and editing, J.I., G.R., A.B., F.G., E.B., E.S., and M.D. All authors have read and agreed to the published version of the manuscript.  
**Funding:** Concerning the activities carried out by the authors affiliated with Bazovye Tekhnologii, LLC, Moscow, this work has been supported by the Ministry of Education and Science of the Russian Federation under the Federal target program \"Research and Development in Priority Directions of the Russian Science and Technology Complex in 2014-2020.\"  
**Acknowledgments:** The authors would like to thank the Shared Facilities Center of the Moscow Institute of Physics and Technology (MIPT) for making available the equipment necessary to carry out the S-parameters measurements reported in this work.  
**Conflicts of Interest:** The authors declare no conflict of interest.