Passive Intermodulation in Metal-to-Metal Contacts Caused by Tunneling Current
Passive intermodulation (PIM) by metal contacts limits the bandwidth and capacity of radio links used in mobile and satellite communications. In this work, we investigate the effect of nonlinearities of metal-to-metal contacts and their effects on PIM generation. An analytical expression is obtained for the tunneling current density which has an error of ~1.6% in the case of a very thin insulator and low voltages in MIM (Metal-InsulatorMetal) junctions. The presented analytical model of the contact surfaces with the fractal geometry is applied to simulate PIM products of third-order (PIM3) and fifth-order (PIM5) versus the contact resistance and applied pressure. The simulation results are validated experimentally by an open-ended rectangular coaxial structure with a slotted enclosure. The measurement results demonstrate that the presented model predicts the PIM with a mean error of about 4.8 dB when the contact pressure varies from 0.5 MPa to 1.7 MPa.
Funding
Huawei Technologies Sweden
History
Email Address of Submitting Author
amir.dayan@liverpool.ac.ukORCID of Submitting Author
0000-0002-9106-7395Submitting Author's Institution
University of LiverpoolSubmitting Author's Country
- United Kingdom