T4.1: L/S band demonstrator critical building block development [M4-M18]

This Task will use output of the previous Task 1.2 and 1.3 for which compact LNA and active antenna TX/RX module specifications have been defined. To be successful both demonstrator developments will have to rely on tight co- development and co design with the SAW development work of Task 2.1 to ensure the required electrical, thermal and mechanical performances for space application. Risk mitigation techniques will be applied at this stage using fast prototyping based on preliminary board design and SAW prototype coming from existing design available at SOI. These SAW filters based on POI technology will be packaged using agile design factory aiming at fast prototyping (see details in section 1.2) available at TAS. This will then allow for fast feedback-loop in design phases and relevant technology building block. S band demonstrator technology building blocks and their associated related manufacturing processes to be considered are given as follow:

• Fast prototyping: Electrical and environmental evaluation through fast bread-boarding activity based on existing

SAW filter (Leader TAS participant SOI, ALT, INC –M4-M10) In order to lower the risk in detailed design phase, the performances of available SAW filter supplied by SOI and packaged by TAS will be analysed and tested especially regarding radiation, humidity, ESD and RF power tests. The development by TAS of dedicated test board will be used to carry out such tests. Based on space application specifications and link to the environmental test plan and test facilities as defined and performed in task T5.3 benchmarking of the technology vs targeted specifications of T1.2 TAS will realize the test board & relevant assembly of Package SAW components using its agile design factory. TAS will also implement RF at various temperatures and RF power testing at board assembly level of SAW filters with support of SOI. The same approach will be conducted on similar representative boards for ESD, and humidity tests by ALT. Assembly of the test board will be performed by TAS. The obtained results will directly feed POI based SAW development and advanced POI based SAW research and development in Task 2.2

• Multilayer PCB: Design, validation and selection of microwave transmission lines and basic interconnects embedded into multilayer circuit boards [Leader: TAS – M5-M8] The interconnection with circuit board of different SMT components and I/O RF interface like connectors needs a special care to match with design to manufacturing and design to cost methodologies. Innovative approach compatible with multi-layered PCB, will be performed with recent advanced embedded waveguide technologies, suitable for operation in the S band to limit electromagnetic radiations which are critical at these low frequencies.
• RF connectors, and shielding at PCB and structure level: to validate RF and EMC design at board and structure level [Leader: TAS – M8-M15]
Based on module level detailed specifications coming from task 1.2, S band connectors and associated passive interconnects will be designed and validated by TAS. To reduce module cost, EM shielding would need to be implemented at PCB level, using all possible features available in other high reliability industrial sectors like automotive.
• PCB and SMT process: to validate PCB stack-up and develop SMT process compliant with SAW filter and other component needed for both LNA and TX/RX active antenna module [Leader: TAS Participants SOI, ALT – M8-M15]
• TAS with support of ALT will validate PCB stack-up at TRL 6 in line with IPC standards instead of high cost ECSS standards applied to ESA qualified PCBs. Considering the BOM defined in task 1.2, TAS will adapt its SMT process for cost optimization and adaptation to new components like POI based filter encapsulated into “New Space” compliant packages. A special care will be taken for TX RF chain where Multiphysics consideration is needed taking into account the electrical, mechanical and thermal constraints as defined into task 1.2. These considerations will aim at extracting SMT design rules to be used into SMT qualification testing of Task 5.3 of new component of the project.
• Preliminary design of S band LNA and TX/RX active antenna front-end [leader TAS – M15-M18] Based on task 1.2 specifications, task 2.2 SAW development and output of development of critical building blocks performed in task 4.1, TAS will perform a preliminary design of both S band LNA and TX/RX active antenna front-end. This task will be concluded with a preliminary design review for both demonstrators that will then feed tasks 4.2 and 4.3.
Leader : TAS
Involved Partners : ALT, SOI