Project: MEMs adjuStable E-band filTers

Future radio link communication necessitate the use of high frequency band, featuring small size, high performance and low cost. The innovative next generation point-to-point radio links target to satisfy the growing need of mobile broadband services demanding extremely high capacity. _x000D__x000D_In this context the E band frequencies are expected to play a key role in enabling challenging and unproven broadband communications missions for a wide range of applications. Among others, one key element in the E-band radio link communications payloads is tunable RF bandpass filters. They will allow one to use only a single component to provide different filtering functions, such as adjacent filtering bandpass responses (i.e. frequency-reconfigurable filters) or filtering responses having different bandwidth (i.e. bandwidth-reconfigurable filters). _x000D__x000D_High Q-factor (˜1000), wide tuning range, low manufacturing cost and also reliability will be highly recommended. The realization of reliable electronically filters can also provide fine tuning solutions, thus allowing for replacing conventional mechanical approaches for fine tuning, such as screws in conventional waveguide filters. _x000D__x000D_RF MEMS technologies is rapidly emerging as an enabling technology to yield a new generation of high-performance RF-MEMS passives, such as RF switches and tunable filters, thanks to their low insertion loss, high linearity, low power consumption, potentially low cost and high integrability with conventional circuits._x000D__x000D_The commercialization of RF-MEMS filters is greatly hampered at the moment by a few critical success factors, namely:_x000D__x000D_• Availability of robust designs, immune from manufacturing tolerances, impedance mismatching due to biasing networks and interconnections with neighboring modules_x000D_• Reliability issues on the RF-MEMS devices (COly represented by the dielectric charging phenomena and contact resistance stability over time) _x000D__x000D_Regarding reliability issues, the most critical point for an RF-MEMS device to be introduced into the commercial market is its long time reliability, both in terms of maximum lifetime and number of ON/OFF cycles that the device can tolerate before stiction to the substrate._x000D__x000D_The objective of the proposed MEMSET project is the development and manufacturing of innovative micro-machined filter at E band, where RF MEMS switches are used for fine tuning and compensation for manufacturing tolerances and interconnection mismatching. _x000D_The proposed application exploits all advantages of RF-MEMS technology in terms of RF-performance and, at the same time, is not influenced by reliability issues, since the switches need to be actuated only one or very few times. Playing a similar role of a mechanical screw in conventional filters at low frequencies, each switch is used to compensate for fabrication tolerances. It is thus actuated only during the initial tuning phase and then needs to be locked for all the rest of its life. _x000D__x000D_This project targets the expanding microwave Mobile Backhaul market and especially the point to point radio market. During recent years, the E-band frequencies have been standardized for use as high capacity point-to-point communication. The standardization within these bands are almost exclusively FDD, i.e full duplex which makes the use of highly selective waveguide filters a necessity._x000D_The proposed application arises from the requests of major world communication companies, such as Ericsson, who need high performance cavity filters at E band for the forthcoming generation of point-to-point radio link communication. Ericson will be a member of consortium and will advice as an end-user. A letters of interest and support signed by the Ericsson AB is attached to this proposal (see annex pg1)._x000D__x000D_The Ps have been selected so that the whole value chain is represented, from design and modeling to environment tests, including fabrication, assembly, and characterization._x000D_The economic exploitation of the project results will be carried out by the two SMEs involved, who will proceed with the pre-industrialization of the filter manufacturing process and commercialization of the devices following the previous advices provided by Ericsson_x000D_The project Ps, along with their CO roles, are:_x000D__x000D_• RF Microtech (SME): Coordinator of the project - support in electromagnetic and thermo-mechanical design of both RF MEMS switch, 0-level packaging and filter, initial RF characterization, coordination and market exploitation of the research activity_x000D_• NovaMEMS (SME): Definition of the test plan and execution of mechanical and environment tests on RF-MEMS switches_x000D_• FBK (R&D): manufacturing of RF MEMS switches and micro-machined cavity filters on silicon CMOS technology and 0-level capping technology supplier_x000D_• CNRS-LAAS: Filter assembly and RF Test and characterization_x000D_• ERICSSON AB: advising as an end user and providing input such as electrical requirements, quality levels and commercially conditions._x000D_

Acronym MEMSET (Reference Number: 7449)
Duration 01/04/2013 - 31/03/2016
Project Topic This project aims at the development of innovative high Q waveguide filters at E band for point-to-point MINI-LINK radio link communications. RF-MEMS switches are used “one-time” to tune the filter response in case of deviations due to manufacturing tolerances and/or impedance mismatch.
Network Eurostars
Call Eurostars Cut-Off 8

Project partner

Number Name Role Country
5 Fondazione Bruno Kessler Partner Italy
5 ELEMCA Partner France
5 RF Microtech S.r.l Coordinator Italy
5 Ericsson AB Partner Sweden
5 Centre National de la Recherche Scientifique Partner France