|Submitter:||Aleksei Dubok (TU/e)|
|Description:|| Focal-plane arrays (FPA) have become an interesting alternative for conventional horn-fed reflector antennas in a number of applications, e.g. in radio astronomy and in Ka-band satellite communication. However, there are limiting factors for using this technology at higher frequencies, such as bandwidth limitation. Nevertheless, the demand for wideband antenna arrays and focal-plane arrays is increasing especially in the Ku- and Ka-band.|
A fiber to RF-FREEspace multiBEAM converter (FREEBEAM) is an STW project, which investigates new multi-beam wideband antenna systems with optical beamforming. A demonstrator will be developed that generates four simultaneous beams in the 20-40 GHz band with an Effective Radiated Power of 100000 W. The partners in the project are ASTRON, NXP, Thales, TNO, Catena, SATRAX, ESO and ESA.
In the framework of the FREEBEAM project, the design of wideband focal-plane arrays is carried out at the Eindhoven University of Technology (TU/e). With an essential help of ASTRON, two versions of wideband antennas have been manufactured successfully. This was a challenging task because the overall size of these antennas is only 15 x 12 mm, with gaps of 100 micron. But thanks to the craftsmanship of Albert van Duin, the prototypes were successfully manufactured.
The picture shows an experiment with probe measurements performed in the mm-wave anechoic chamber at the TU/e. The modified bow-tie antennas have been used as a first step in the design as a wideband array element to be used in a FPA. The presented simulation and measurement results demonstrate good agreement for both antenna versions and could be considered as a good confirmation of the selected antenna development strategy. These results will be used as a starting point for the wideband FPA design in the FREEBEAM project.