Novel Coupling Coaxial Adapter for Portable Passive Intermodulation Test of Coaxial Cable

This work demonstrated a novel coupling adapter for cable PIM test. For this adapter, the connection at the inner and outer conductors are all achieved by dielectric coupling. The direct metal contact and contact uncertainties at the connection junction can be avoided, thus the potential PIM uncertainties can all be avoided. In this design, a coupling equivalent circuit model is used to optimize the coupling structure. In the application, there is no need to specially connect the cable by direct physical hard contact, thus the potential contact PIM product can be avoided. The experiments prove that the residual PIM level of this adapter can be optimized to below -125 dBm@2×43 dBm, while reducing PIM fluctuation under vibration conditions by approximately 5 dB compared to a normal hard contact jacket connector.