NPL and Flann Microwave receive international recognition

4 minute read

NPL and Flann Microwave Ltd. have been recognised with the Best Oral Presentation Award at the 107th Automatic RF Techniques Group (ARFTG) Microwave Measurement Conference for collaborative research demonstrating a new miniature rectangular waveguide interconnect for millimetre-wave and sub-terahertz applications.  

Presented by NPL scientist James Skinner, the award-winning paper, Design and RF Performance Validation of a New Miniature Rectangular Waveguide Flange for Millimeter-wave Frequencies and Above, describes the design of the new FSM-45 waveguide interconnect developed by Flann Microwave, a UK-based manufacturer of precision microwave components, and its independent test and evaluation by NPL.  

The research addresses a longstanding challenge in high-frequency waveguide systems. Conventional waveguide interfaces, which form the basis of today's IEEE standardised waveguide interfaces, become disproportionately large relative to the waveguide opening at millimetre-wave and sub-terahertz frequencies, creating constraints for increasingly compact RF systems. The FSM-45 was developed to provide a substantially smaller footprint while maintaining the alignment precision required for high-performance applications.  

NPL's evaluation of the interface at frequencies up to 330 GHz demonstrated excellent electrical performance; the results for the FSM-45 matched or exceeded the performance of the current IEEE flange design, which is regarded as the benchmark interface for frequencies above 110 GHz.  

"This work demonstrates that reducing the size of a waveguide interface does not require a compromise in performance," said James Skinner, Higher Scientist at NPL and presenter of the paper. "Our results showed that the FSM-45 not only achieves a much smaller footprint but can also deliver electrical performance that equals or surpasses the current state of the art." 

Ian Burnage, CEO of Flann Microwave Ltd, said: "Innovation is only valuable when you can prove that it actually makes a difference.  Working with NPL allowed us to independently validate the performance of our new FSM-45 waveguide flange and communicate those results with confidence to the RF community.  Our collaboration has spanned decades, and it continues to be both technically rewarding and genuinely enjoyable.  We are delighted that the collaboration has also been recognised with the Best Oral Presentation Award at ARFTG." 

Professor Nick Ridler, Departmental Head of Science, Electromagnetic and Electrochemical Technologies, NPL, said: “This collaboration successfully combines Flann Microwave's expertise in the design and manufacture of precision microwave components with NPL's world-leading capabilities in electromagnetic metrology and measurement science.”  

The work was supported by Innovate UK's Analysis for Innovators (A4i) programme and highlights the role of collaborative innovation in accelerating the development of next-generation RF and millimetre-wave technologies.  

NPL and Flann Microwave continue to collaborate on developing improved measurement solutions and standards that enable innovation across the RF, microwave and millimetre-wave sectors. 

The full paper details are shown below and the paper is available here.  

J. Skinner, D. Richardson, P. Hague and N. M. Ridler, “Design and RF Performance Validation of a New Miniature Rectangular Waveguide Flange for Millimeter-wave Frequencies and Above”, 107th ARFTG Microwave Measurement Conference, Boston, MA, USA.

05 Aug 2026