DEVELOPMENT OF SUPERCONDUCTOR NIOBIUM-BASED MILLIMETER-WAVE FILTERS
Abstract
DEVELOPMENT OF SUPERCONDUCTOR NIOBIUM-BASED MILLIMETER-WAVE FILTERSSOWFunds are provided to explore the feasibility of designing and producing potentially cofabricatable Nb, sharp skirted (high Q) analog filters for RF receiver used for extremely wideband reception, to above 200 GHz.ObjectiveThe objective is to confirm that high Q factor analog filters can be realized in niobium superconductor fabrication technologies available for US government work at millimeter-wave frequencies from Ka band, through V,E, and W and even extending to H band (220-325 GHz). This availability will guarantee that superconducting receivers can be created across this entire frequency band as suggested by preliminary measurements.ApproachThe approach is to utilize a combination of fabrication processes available at U Waterloo for analog applications and at MIT Lincoln Labs for both passive and active Nb circuits. The last will allow fabrication of these filters feeding Nb analog to digital converters (ADC) with no intermediate connectors of noticeable electrical loss. That will both help RF performance and reduce receiver assembly costs and volume. Three kinds of structures will be investigated: slot resonators for use in conventional planar coupled resonator filters, waveguide filters in both rectangular and ridge 3 dimensional sorts, and back-etched, micromachined cavity resonators. Multi-layer, thin film fabrication techniques will be used in all cases. Preliminary measurements of the microwave loss tangents of the dielectrics used and surface resistance of the superconducting Nb conductors at these same aggressive frequencies is a necessary first step toward the initial design work.Mission / RelevanceRF activity of both commercial and military sorts is expanding rapidly to frequencies up to 100 GHz and that trend will not stop soon because it is driven by the desire for ample uncontested bandwidth. Even though very narrow band, interference rejection filters will not be needed at these frequencies for some years, high Q filters are still needed for any receiver that needs to subband these gigantic swaths of frequency, for example, in order to receive only one Nyquist band at a time per channel so that there is no ambiguity with respect to the carrier frequency. The higher the Q, the lower will be the issue with multiple channels hearing the same signals near the cross over points. Thus in order to maintain future situational awareness this early work on RF components for future receivers is required. The principal investigator of this project, Professor Mansour, has over 30 years of accumulated industrial and academic experience and has 35 US and Canadian patents and over 350 refereed publications to his credit. He is very active in international EE device forums such as the International Microwave Symposium. His group has over 15 students and a strong equipment and software tool set. The team is very strong and has consistently delivered new device concepts for ONR on previous grants.Foreign justification:Dr Mansour s group is not only a world leader in this sort of work. It is also almost the only academic group that includes both normal metal and both low and high temperature materials in its filter investigations, along with developing MEMS technology. There is no obvious rival academic research group in the US and developing one from scratch would be extremely cost ineffective. When he worked for ComDev, Dr Mansour had a NATO clearance and the US has a particularly close relationship with Canada.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2016
- Source ID
- N000141612636
Entities
People
- Raafat R. Mansour
Organizations
- Office of Naval Research
- United States Navy
- University of Waterloo