Characterizing Measurements for Wireless Power Transfer (WPT) Systems

With the evolution of cloud computing systems and highly integrated mobile terminals, various types of digital contents and applications can be enjoyed in the palm of your hand today. As a result, power consumption in mobile terminals rapidly increases, raising demands for more convenient and versatile ways of battery charging. Wireless Power Transfer (WPT) technology has drawn much attention recently as one of the realistic solutions and is widely discussed and researched.

The theory of wireless power transfer by inductive coupling between coils/resonators has been well known for some time. Today there are already many commercialized products to wirelessly transfer power using the magnetic induction method. In addition, the demand for wireless power transfer using the magnetic resonance method is growing mainly due to its flexibility in charging range and capability to charge multiple-devices. Compared to power transfer through wirelines, power transfer in air has larger power loss. Therefore, power transfer efficiency in WPT systems is one of the challenges for WPT technology, and it largely relies on quality of components used in these systems. To ensure system performance and interoperability, it is important to specify test requirements and perform tests according to them. In this application note, we will review components used in WPT systems as well as measurement requirements and solutions with Keysight ENA Series network analyzers.