Stage-by-stage evaluation of a biomedical system regarding its electromagnetic susceptibility

Electromagnetic interference has been the cause for many failures of medical devices over the past years. All these devices have to undergo a series of tests to validate its conformity regarding electromagnetic compliance. This work presents the results of research done on a certified biomedical system to identify the potential improvements of such an apparatus concerning interference. A first evaluation of the electrodes alone shows how the material they are made of can play a role on how easily electromagnetic interference couples to these. Furthermore, the electronic circuits of the system are also evaluated as their role is to filter all the undesired signals and leave only the biosignals. Finally, a real world use case scenario is replicated inside the anechoic chamber in the presence of a disturbing signal with results showing that by applying a signal modulated at a frequency in the range of the biosignals sensors pass band is enough to rend its acquired signal worthless.