Self Tuning Inductive Powering For Implantable Telemetric Monitoring Systems

Abstract

Inductive powering of implantable monitoring devices is a widely accepted solution to replace implanted batteries. However, this method demands technically skilled operators to constantly tune the power link parameters. This becomes particularly important when the entire system must be portable. Acceptable battery lifetimes can only be obtained by a precise optimisation of the power efficiency. In this paper, a technique is presented to render the system fully compatible with a hospital environment. Multiple automatic tuning loops are incorporated to handle component tolerances and coil movements, and to optimise the power efficiency on a continuous basis. The problem of mechanical strain sensing in femoral nailplates, is shown as an example.