ESA – ARTES Advanced Technology

Prime Contractor
Pasquali Microwave Systems srl (Firenze, Italy)

Subcontractors
Consiglio Nazionale delle Ricerche (CNR)

Istituto di Elettronica e di Ingegneria dell’Informazione e delle Telecomunicazioni (IEIIT) (Torino, Italy)

Politecnico di Torino (POLITO)

Department of Management and Production Engineering (DIGEP) (Torino, Italy)

Argotec srl (Torino, Italy).

Key people
O. A. Peverini (CNR-IEIIT), G. Addamo (CNR-IEIIT), M. Lumia (CNR-IEIIT), G. Virone (CNR- IEIIT), F. Calignano (PolitTO), R. Mandolesi (Pasquali Microwave Systems, University of Ferrara), M. Biggi (Pasquali Microwave Systems), G. Matticari (Pasquali Microwave Systems), A. Ferrara (Aergotec), N. J. G. Fonseca (Anywaves, Toulouse).

Content
The satellite communication market is evolving towards medium-volume production of antennas and associated front-ends. Indeed, in GEO applications, complex focal plane arrays of hundreds of feed chains and BFNs are required to implement Tbps VHTS systems. In LEO and MEO applications, constellations of several hundreds or even thousands of low – cost small satellites are already in operation or will be deployed in the near future. In this framework, Additive Manufacturing (AM) technologies are being steadily investigated and exploited for the development of RF equipment for satellite communication payloads. Indeed, AM technologies provide several advantages with respect to conventional machining, among which are free-form capability and fit-for-purpose design. These two specific aspects of AM enable the integration of different functionalities in a single monolithic part, thus reducing the number of parts, costs, lead time, and MAIT activities.

The current projects shows the results achieved within the ESA Contract ARTES No. 4000130886/20/UK/AB i.e. a K/Ka-band dual circular-polarization antenna feed system with integrated RF, thermal and mechanical functionalities that was developed through AM. Based on a trade-off in terms of RF requirements and potential configurations, the K/Ka-band antenna-feed chain consists of a smooth-wall feed-horn and an asymmetrical feeding-network. Indeed, when exploiting novel asymmetrical architectures, it is expected that AM technologies will allow for developing very compact configurations of dual-band dual – polarization feed-chains compatible with lattice steps of the focal-plane array in the order of 20 mm. Three different configurations of asymmetric feeding-networks were bread-boarded, which consists of, respectively:

A) A dual-band septum polarizer, and two diplexers.
B1) An asymmetric K-band ortho-mode junction, two low-pass iris filters, a Riblet coupler, and a Ka-band septum polarizer.
B2) An asymmetric K-band ortho-mode junction, two low-pass stub-filters, a H-band coupler, and a Ka-band septum polarizer.

All the three configurations were defined according to the general design rules of RF components for additive manufacturing. For each architecture, a breadboard was manufactured through the LPBF process in AlSi10Mg alloy and tested. Based on the measured performance of the three breadboards, configuration B2 was selected for the development of an Engineering Model (EM) with integration of thermal and mechanical functionalities. Specifically, the heat exchanger of a single-phase pumped cooling system was integrated in the feeding network along with mechanical adapters to meet the standard flanges of the RF measurement setup. The EM was 3D-printed, internally passivated with Lanthane 613.3, and externally painted with Aeroglaze Z 306 paint. The EM was subjected to a space pre-qualification campaign, including RF sessions (before and after thermal/vibration/TVAC) and thermal tests with the goal of achieving a TRL near to 6 in view of possible future flight applications. The tests and successful results on the EM confirms the validity of the design and manufacturing approach and paves the way for a continuation of activities aimed at obtaining a higher TRL.