30.11.2021
The new 1.35 mm coaxial connector for frequencies up to at least 90 GHz, developed by a German consortium and with the participation of PTB, has now been included in national and international standards. Industrial companies worldwide have integrated the new connector in many products and in measuring instruments.
Internationally, there has been great interest in the introduction of a new high-frequency coaxial connector since 2017. In addition to PTB, also the Japanese National Metrology Institute (NMI) AIST-NMIJ has taken up the development of traceable measurements. In frame of the European metrology research project 
“TEMMT” (2019 to 2022), first measurement comparisons between European NMIs were performed.
Corresponding work in standardization committees with contributions from PTB started in 2017, and the international standard IEC 61169-65 Ed. 1.0 b:2021 has now been published and can be obtained, as well as its German translation DIN EN IEC 61169-65 (VDE 0887-969-65). The American standard IEEE 287, which is also very important internationally, likewise has added the new connector. It now includes 13 precision connectors for RF signals up to a frequency of 170 GHz. A new edition is expected to be published at the turn of 2021/2022.
The new connector closes the gap between the two established connectors 1.85 mm (up to 67 GHz) and 1.00 mm (up to 110 GHz). The advantages of the new connector are that it covers the frequency range up to at least 90 GHz, has a metric fine thread, optionally brings a push-pull coupling (rapid connection), and that the repeatability of the connection is comparable to that of the 1.85 mm connector. Also, the diameter of the connector pin is identical to the inner conductor diameter of the established type 0.047 cable, which not only provides a safe and simplified, but also an inexpensive cable connection for many industrial applications.
Figure: Variety of products coaxial connectors type 1,35 mm. Picture from Rohde & Schwarz, Rosenberger und SPINNER (alphabetical order).
Department 2.2 „ High Frequency and Electromagnetic Fields“