@article {20_IEEE ACCESS_LUCAS POLO_ARRAY DESFASADORES TORNILLOS, title = {Mechanically Reconfigurable Linear Phased Array Antenna Based on Single-Block Waveguide Reflective Phase Shifters With Tuning Screws}, journal = {IEEE Access}, volume = {8}, year = {2020}, pages = {113487-113497}, abstract = {This work presents the design and prototyping of a reconfigurable phased array in Ku band (16 to 18 GHz) implemented in waveguide technology. The design is based on the use of a novel seamless waveguide module integrating four reconfigurable phase shifters to adjust the relative phase shift between the unitary elements of a linear array, which are illuminated uniformly by a corporate waveguide feeding network. The phase shifters are implemented by a 90{\textdegree} hybrid coupler in waveguide technology where two of its ports are loaded with a tunable reactive load, implemented in this proof of concept with a tuning screw. The four phase shifters have been manufactured in a single part using direct metal laser sintering, avoiding the losses related to bad electric contacts and misalignments associated to multipart devices. This also simplifies the assembly of the full phased array, leading to a modular approach with three parts whose design can be addressed separately. The experimental results for the complete array antenna show great performance and demonstrate that the main-lobe of the radiation pattern can be effectively scanned continuously between the angles -25{\textdegree} and 25{\textdegree}, with a high efficiency in the whole design band thanks to the proposed waveguide implementation.}, keywords = {antenna radiation patterns, Beam steering, Couplers, Fasteners, linear antenna arrays, phase shifters, Phased arrays}, issn = {2169-3536}, doi = {10.1109/ACCESS.2020.3003193}, author = {L Polo-Lopez and J L Masa-Campos and A T Muriel-Barrado and P Sanchez-Olivares and E Garcia-Marin and J C{\'o}rcoles and J A Ruiz-Cruz} } @article {18_AWPL_PABLO-SANCHEZ_CORPORATE-ARRAY-TUNING-SCREWS, title = {Mechanically Reconfigurable Linear Array Antenna Fed by a Tunable Corporate Waveguide Network With Tuning Screws}, journal = {IEEE Antennas and Wireless Propagation Letters}, volume = {17}, number = {8}, year = {2018}, month = {Aug}, pages = {1430-1434}, abstract = {A mechanical technique to provide beam-steering capabilities to a linear array antenna is presented. The methodology is based on the insertion of metallic tuning screws into power dividers in rectangular waveguide technology. These tuning screws establish a short circuit between the top and bottom plates of the waveguide, and a phase change in the transmitted signal is then generated. Therefore, the phase difference between the output ports of a conventional waveguide divider can be controlled with these tuning screws. A corporate waveguide feeding network with several tuning screws has been designed. This tunable waveguide network is used to feed an aperture stacked patch array, forming the final mechanically reconfigurable linear array. Seven different phase configurations have been synthetized by using the tuning screws, which provide a noncontinuous angular scanning. In particular, a main beam steering from -26{\textdegree} to +26{\textdegree} with 13 discrete radiation patterns has been obtained. The use of waveguide technology makes the proposed reconfigurable antenna suitable for low-loss and high-power applications. Total efficiency values higher than 90\% have been achieved for every configuration.}, keywords = {Aperture-coupled antennas, Beam steering, Electromagnetic waveguides, Fasteners, linear antenna arrays, microwave antenna arrays, Tuning, waveguide arrays}, issn = {1536-1225}, doi = {10.1109/LAWP.2018.2848911}, url = {https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=8388289}, author = {P Sanchez-Olivares and J L Masa-Campos and A T Muriel-Barrado and R Villena-Medina and G M Fernandez-Romero} }