Antenna design for ultra-compact Bluetooth devices

This paper presents a solution for an ultra-compact antenna for small Bluetooth devices. The work considers the battery and the electronic components influence in the antenna design process for a real device, i.e. a Bluetooth tracker. Three different models for representing the battery and the main electronic components are studied: (i) a simple model that represents both battery and components by a ground plane; (ii) a model that represents the battery realistically and the components by a ground plane and (iii) a model that represents realistically both battery and components.