@article {19_IJRFMCAE_LUCAS_DESFASADOR_PLANO_H_DMLS, title = {Reconfigurable H-plane waveguide phase shifters prototyping with additive manufacturing at K-band}, journal = {International Journal of RF and Microwave Computer-Aided Engineering}, volume = {29}, number = {12}, year = {2019}, pages = {e21980}, abstract = {Abstract This work presents the design and manufacturing of a K-band reconfigurable phase shifter completely implemented in waveguide technology for reduced insertion loss, good matching, and large phase shifting range. The device is based on the combination of a short slot coupler and two tunable reactive loads implemented as a section of short-circuited waveguide where an adjustable metallic post is inserted. Three prototypes of this design have been manufactured using different techniques (conventional computer numerical control machining, a low-cost fused filament fabrication technique and direct metal laser sintering) in order to assess its performance for different applications. The prototypes have been characterized experimentally and the achieved results are evaluated and compared. The proposed phase shifter, since it is fully developed in waveguide technology, eliminates the need of adding transitions to planar structures in order to integrate lumped components like pin diodes or varactors. Therefore, this device has a great potential in high-power beam steering phased arrays.}, keywords = {additive manufacturing, fused filament fabrication, phase shifter, reconfigurable, selective laser sintering, waveguide}, doi = {10.1002/mmce.21980}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/mmce.21980}, author = {L Polo-Lopez and J L Masa-Campos and J A Ruiz-Cruz} } @conference {14_EuCAP_Leal-SevillanoRuiz-CruzMontejo-GaraiEtAl_NovelDual-BandSingle, title = {Novel Dual-Band Single Circular Polarization Antenna Feeding Network for Satellite Communications}, booktitle = {Proc. 2014 European Conference on Antennas and Propagation (EuCap)}, year = {2014}, month = {Apr.}, pages = {1-5}, abstract = {In this paper a novel dual-band single circular polarization antenna feeding network for satellite communications is presented. The novel antenna feed chain1 is composed of two elements or subsystems, namely a diplexer and a bi-phase polarizer. In comparison with the classic topology based on an orthomode transducer and a dual-band polarizer, the proposed feed chain presents several advantages, such as compactness, modular design of the different components, broadband operation and versatility in the subsystems interconnection. The design procedure of this new antenna feed configuration is explained. Different examples of antenna feeding networks at 20/30 GHz are presented. It is pointed out the excellent results obtained in terms of isolation and axial ratio.}, keywords = {antenna, Circular polarization, diplexer, dual-band, K/Ka band, multibeam, orthomode transducer, polarizer, satellite communications, waveguide}, author = {C A Leal-Sevillano and J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M} }