@article {20_ANTENA_ARRAY_DUAL_SLOT_BOMBARDERO_KUMAR, title = {Dual-linearly polarized travelling-wave array antenna based on triple plus slots fed by square waveguide}, journal = {AEU - International Journal of Electronics and Communications}, volume = {119}, year = {2020}, pages = {153176}, abstract = {A dual-linearly polarized travelling-wave array antenna design at Ku-band composed by a novel single element named as triple plus slot is presented. It is formed by a plus slot with an additional pair of short auxiliary slots. The generation of the dual polarization is based on the two degenerated modes TE10 and TE01 supported by a square waveguide following a series feeding topology. Following the operation principle of the conventional plus slot, the transversal slot is only excited by the TE10 mode to generate vertical polarization while the longitudinal slot is only excited by the TE01 mode to generate horizontal polarization. The auxiliary slots provide new degrees of freedom to the antenna design process that allow to accomplish some strict requirements and overcome some design issues. Thus, the proposed triple plus slot has been experimentally validated in a dual-linearly polarized travelling-wave array configuration. The antenna has been fabricated and measured, providing some features such as high efficiency (>80\%), high gain (>13~dB) with a 1~dB-gain bandwidth higher than 10\%, grating lobe mitigation, high isolation between orthogonal polarizations (>25~dB) as well as a fractional impedance bandwidth (S11~<~-14~dB) higher than 11.7\% (from 16 to 18~GHz).}, keywords = {Antenna arrays, Dual-polarized antennas, Slot antennas}, issn = {1434-8411}, doi = {https://doi.org/10.1016/j.aeue.2020.153176}, url = {http://www.sciencedirect.com/science/article/pii/S1434841119332042}, author = {P Sanchez-Olivares and J L Masa-Campos and E Garcia-Marin and D Barrio-Tejedor and P Kumar} } @article {19_MOTL_BRANDE_ARRAY UWB, title = {UWB four elements antenna array}, journal = {Microwave and Optical Technology Letters}, volume = {61}, number = {5}, year = {2019}, pages = {1284-1294}, abstract = {Abstract In this work, a planar UWB four elements antenna array with and without notch filter is designed. The feeding system of the array is an UWB four branch multiple segment power divider/combiner. Each branch has a three segments impedance transformer. Measurements show that the array works well within the band 3.1 to 10.6 with S11 lower than -10 dB. It is shown that the maximum gain varies with the operating frequency having a value of 8 to 12.3 dB and that it is higher than the gain of the single element.}, keywords = {antenna array, notch filters, ultra-wideband antennas}, doi = {10.1002/mop.31664}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/mop.31664}, author = {B T Ahmed and J L Masa-Campos and D Brande-Hern{\'a}ndez} } @conference {13_URSIESP_Mecia-OlivaGrajal-de-la-FuenteBadolatoEtAl_Experimentalradarimager300GHz, title = {Experimental radar imager with sub-cm range resolution at 300 GHz}, booktitle = {Proc. 2013 Simposium Nacional URSI (in Spanish)}, year = {2013}, month = {Sept.}, pages = {1-7}, abstract = {This paper presents a high range resolution radar sensor working in the submillimeter-wave band for standoff detection and security applications. Low-cost technologies have been properly selected in order to implement a versatile and easily scalable radar system. A large operational bandwidth, required for high range resolution, is attained by means of a frequency multiplication-based architecture. This radar system sweeps a bandwidth of 27 GHz. The final application allows the generation of 3D images by means of the radar front-end integrated with a bifocal ellipsoidal Gregorian reflector system. The scene of interest is elliptically scanned at a standoff range of 8 m. In addition, some of the design and fabrication techniques of components at the millimeter and submillimeter-wave bands are presented.}, author = {Mecia-Oliva, B and Grajal-de-la-Fuente, J and Badolato, A and Garcia-Pino, A and Besada-Sanmartin, J L and C A Leal-Sevillano and J A Ruiz-Cruz and Montejo-Garai, J R and Rebollar, J M} } @conference {09_IMS_MongeRuiz-CruzAnzaEtAl_HighPowerDualMode, title = {High Power analysis and design of dual-mode channel filters}, booktitle = {2009 IEEE MTT-S International Microwave Symposium Digest}, year = {2009}, month = {June}, pages = {1353-1356}, abstract = {In this paper, we present two dual-mode channel filter topologies which are able to withstand more than 600 W in Ku-Band. The two different designs (one with elliptical cavities and the other one with rectangular cavities) implement the same transfer function: four order, elliptical response centered in 12GHz, with 40MHz bandwidth and two transmission zeros. It is shown that the critical dimensions for the power-handling of these filters are the dimensions of the input-output irises. In fact, in order to rigorously obtain these conclusions and to reach these high-power levels (including margins), it is essential to use the advanced numerical techniques described in the paper to predict the multipactor effect. Moreover, the standard approach for multipactor onset prediction based on computing the voltage inside the component is shown to be too conservative and difficult to apply to many practical filter configurations.}, issn = {0149-645X}, doi = {0.1109/MWSYM.2009.5165956}, url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=5165956\&isnumber=5165586}, author = {Monge, J and J A Ruiz-Cruz and Anza, S and Vicente, C and Zaki, K A and Montejo-Garai, J R and Rebollar, J M and Gil, J and Gimeno, B., and Boria, V E} }