DISCO - DISCO- DIplexer at S-band in COmpact technology for small satellite applications

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The objective of DISCO project is the development of breadboards for two different design concepts of S-band diplexer for TT&C systems. Engineering models have to be manufactured and tested to validate the concept. The device has to separate receive and transmit path, saving volume and mass compared to the commonly used bulky diplexer. The significant reduction of volume is a driving requirement in small satellites application. Low loss and high rejection levels are required to the filtering channels. A goal of the project is to push the technology research to find a good compromise between RF performance and volume occupation. Commonly used coaxial resonator technology leads to bulky diplexer solutions and the exploration of advanced manufacturing techniques combined with novel dielectric materials can reduce the size, enabling better integration with the whole TT&C unit.


The main challenge of DISCO project is the dramatic size and mass reduction requirement combined with the high rejection and low-loss constrains.

The selection of advanced technologies forces to push at the limit some fabrication processes introducing several manufacturing challenges both in term of outcomes and achievable tolerances. The power levels are moderate but the use of the diplexer in TT&C application forces to consider critical phenomenon like Corona discharge.

The goal of compactness affects the sensitivity of the component to power phenomena which represent, even with moderate power levels, a critical aspect.


The main benefit of the new product is the significant mass and volume reduction with respect to standard technology (>50% of volume saving).


The DISCO project is based on ceramic loaded resonators exploiting resonant modes that keep constrained the size of the device. Additive manufacturing on metal is considered to add freedom in the mechanical design of the parts and to lighten the diplexer.

System Architecture

S-band TT&C systems are commonly used in telecommunication satellites for the link between the spacecraft and ground stations during flight and orbit raising until the satellite reaches its nominal orbit. TT&C systems commonly comprise a diplexer which separates receive and transmit paths. The proposed diplexer is used in such application.


The entire work of the project is organized and divided into two technical parts.

In the first parts, the most promising technology concepts are planned to be tested at BB level, leading to the final design concept selection. In the second part, EMs close to a final product have to be designed and subjected to an extensive environmental and RF test campaign.

Current status

The project is in early stage.

BDR meeting of the project is scheduled for September 2023.

The next step of the research activity on this topic is the identification of two impementation concepts to design the first breadboards of the filter.

Prime Contractor