Medium-range inductive wireless power transmission systems allow a sufficient power transfer without requiring close proximity between a primary coil and a secondary coil. We briefly investigate the range of a typical system and its radiated emission, from the perspectives of electromagnetic compatibility (EMC) and human exposure requirements. We then discuss the applicable legislation in the European Union, the main question being the applicability of the R&TTE or radio equipment directives. Our conclusion is that this applicability depends on multiple parameters, among which is the presence of a self-tuning capability or of a transmitter control based on telemetry. 1. Introduction Varying electric fields and magnetic fields can be used for wireless power transmission (WPT) from the antenna of a power-transmitting unit to the antenna of a power-receiving unit. WPT using electrically small coils as antennas is usually referred to as inductive WPT. Here, the antenna used in the power-transmitting unit is a primary coil and the receiving antenna is a secondary coil, as shown in Figure 1. The primary coil and the secondary coil form a transformer having a primary and a secondary which are mechanically separable. When the two are placed in proper orientation and proximity, the coupling becomes sufficient to allow an adequate power transmission. Figure 1: An inductive WPT system. In a short-range inductive WPT system, power transmission takes place only when the power-transmitting unit and the power-receiving unit have a well-defined position with respect to each other and are in mechanical contact with each other. Thus, the primary and secondary coils are typically a few millimeters apart and a good efficiency can be obtained. Short-range WPT systems are for instance used in chargers for the rechargeable batteries of hand-held battery-operated items, such as electric tooth brushes, radio transceivers, and cellular telephones. This approach allows the hand-held item to be completely sealed and uses no electrical connection between the mains and the hand-held item. This paper is about medium-range inductive WPT systems, which do not require a close proximity between the primary and secondary coils during power transmission. For instance, an experimental medium-range inductive WPT system (MRIWPTS) was used to power-feed a light bulb over a distance of 2？m [1–3]. The added convenience of positioning-free operation entails an increased emission level, which can exceed electromagnetic compatibility (EMC) and human exposure requirements (in this paper, human
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