Logo of the Physikalisch-Technische Bundesanstalt

Traceability for novel 1.35 mm connector


As first national metrology institute worldwide PTB has set up traceable scattering parameter measurements with the new coaxial connector of type 1.35 mm. The connector covers frequencies up to 90 GHz and will be included in the next issues of the relevant IEEE and IEC standards. This is the result of a cooperation to develop a connector for E-band applications, in which PTB has been involved together with partners from German industry since 2017.



The new connector closes the gap between the two established connectors of types 1.85 mm and 1.00 mm. The latter covers frequencies up to 110 GHz, but it requires a fine-mechanical accuracy during assembly, and frequently loosens during use. The 1.85 mm connector is sufficiently robust for industrial applications and has better repeatability than the 1.00 mm connector, but it is only designed for frequencies up to 70 GHz. New industrial applications at frequencies above 70 GHz require suitable and robust coaxial interfaces, e.g. automotive radar in the frequency range between 76 GHz and 81 GHz, or the WiGig extension IEEE 802.11ay with frequencies up to 71 GHz.

The advantages of the new 1.35 mm connector are that it covers the frequency range up to at least 90 GHz, has a precise metric fine thread, optionally comes with a push-pull coupling (quick 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 makes the new connector a safe and simplified, but also inexpensive cable connection for many industrial applications.


New coaxial connector type 1.35 mm

 Figure 1: New coaxial connector type 1.35 mm



Department 2.2 High Frequency and Electromagnetic Fields