The objective of the activity is to develop a passive low-power distribution network to support 1000-fixed-beam-class Ka-band antennas.
Targeted Improvements: Enabling technology development for beam forming networks capable of handling 1000 fixed beams.
Emerging new telecom applications for Very-High-Throughput-Satellites (i.e. ICE programme) require a very high number of beams (i.e. about 1000). State-of-the-art antenna solutions for the first generation of high throughput satellites are based onpassive antennas (possibly adopting beam hopping) that are able to generate about 200-300 beams. For the next generation, requiringan increase in the number of beams and antenna performance, active antennas (characterised by distributed amplification at radiating element level) have been identified as a key enabling architecture in order to guarantee flexibility and reconfigurability of pattern and power allocation.
The availability of beam-forming networks with a high number of beam ports and radiating element ports is particularly challenging for the realization of 1000-beam-class active antennas, and solutions based on the current technology (i.e. Butler-matrix-based) would result in unacceptable mass, volume, and complexity.
Active antennas based on bi-dimensional lenses (e.g. Rotman lenses), or three dimensional discrete lenses with free-space excitation, are particularly attractive because they permit acombination of the signal distribution and recombination functions, as done by Butler matrixes, but at the same time offer more flexibility (e.g. excitations are not forced to be orthogonal, sparse array layouts can be adopted, etc.).
In this activity a compact, 3 GHz-bandwidth, passive distribution network for a 1000-beam-class Ka-band active antenna shall be designed, manufactured and tested at breadboard level.