Depends on feeding network. You can achieve >3GHz for single element with magnetoelectric dipole antenna (me-dipole slot antenna) or aperture coupled patch antenna.
Usually the array antenna bandwidth is not much greater than the bandwidth of a single antenna element.
Frequency bandwidth of an array is affected by many factors, as: change of element input impedances with frequency due to element coupling and due to beamsteering, by change of element spacing in wavelengths, and also by feeding structures used.
I think that for your bandwidth requirements a Vivaldi array would be a good option:
Depends on feeding network. You can achieve >3GHz for single element with magnetoelectric dipole antenna (me-dipole slot antenna) or aperture coupled patch antenna.
Usually the array antenna bandwidth is not much greater than the bandwidth of a single antenna element.
Frequency bandwidth of an array is affected by many factors, as: change of element input impedances with frequency due to element coupling and due to beamsteering, by change of element spacing in wavelengths, and also by feeding structures used.
I think that for your bandwidth requirements a Vivaldi array would be a good option:
thank you so much for your explanation and the Vivaldi paper. I studied it. It has a good bandwidth. However, I am trying to get a good bandwidth from aperture coupled feed patch antenna.
I think 3.5GHz may be enough at 28GHz for 4x4 corporate feeding with some microstrip t-junction optimizations. Google for wideband microstrip t junction / wideband corporate feed.
I think 3.5GHz may be enough at 28GHz for 4x4 corporate feeding with some microstrip t-junction optimizations. Google for wideband microstrip t junction / wideband corporate feed.