@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} }