Description
The objective of this activity is to develop, breadboard and experimentally test a concept of a distributed modular active antenna based on digital conversion and processing close to the aperture for future Very High Throughput Satellites (VHTS). This includes a digital interface concept between the antenna and the on-board processor enabling a deployable active antenna.
Targeted Improvements: Reduction in the large number of on-board processor interfaces (e.g. RF cables) by an order of magnitude, thereby enabling the deployment of an active antenna due to the digital interface concept.
Description:
Future VHTS systems require a large antenna aperture resulting in the need for a highly modular active phased array. Simply scaling current active antenna architectures isnot viable as it results in unacceptable mass, volume and power consumption. Another challenge is the complex calibration of large active antennas. A distributed and modular digital active antenna could overcome some of the major technical challenges. It would allow the distribution of digital signals between modules and a single connection to a central processor (e.g. optical), resulting in large mass savings compared to an analogue signal distribution network. Being digital, each antenna module could also independently carry out self-calibration/equalisation and the first stages of signal processing (e.g. digital beamforming), thereby reducing the calibration complexity and saving mass from the calibration harness.
This activity will explore active antenna architectures in which the down-conversion, digitisation and first steps of digital beamforming are embedded in the antenna module/sub-array. The activity willtrade-off different architectures, including critical aspects such as the level of integration, modularity, sub-array to sub-array communication strategies and signal distribution to main processor (e.g. by means of photonics technologies). A representative module of a digital active antenna will be designed, breadboarded and tested, including the RF-chain, mixed signal subsystems and representative interfaces.