JultikaUniversity of Oulu repository

Abstract

Mechanical vibrations will affect the performance of the wireless link especially with coming 6G systems, which will operate at significantly higher frequencies than current 5G networks. The mechanical vibrations affect the frequency generation circuitries of the radio equipment and thus the performance of the radio link. The amount mechanical vibration to the radio or any equipment has been standardized and a short summary of related standards has been given in the thesis.

Some practical measurements have been performed to verify the effects of mechanical vibration on wireless link performance. The measurement has been done with a vector signal analyzer that measures the S-parameters of the wireless link. The phase response of the measured S-parameters has been studied to illustrate the phenomena.

The mechanical vibration has been measured with a mobile phone application which detects the changes, vibrations, and location changes of the mobile phone when it was placed over the frequency extender. As a result of the selection of frequency extenders, the RF measurement equipment has been able to perform over a greater frequency range than was originally intended. The used mobile phone application was the G-force meter, which is freely available from application stores.

The measured S-parameters S11 and S21 were analyzed with Matlab software which was provided for the purpose. The measured S-parameters and vibration results have been time synchronized in the Matlab result post-processing. The measurement results show clearly that mechanical vibrations influence the radio signal phase and thus it needs to be considered in the future development of 6G.