QUESTION

Question

We need to use a very small PCB of diameter 10mm for an in-the-ear hearing aid. The DSP runs a custom BTLE stack at 2.4GHz. Due to the real estate limitation and the proximity of the battery and other metallic components, it is not possible to allow much free space behind the antenna so we are looking for a ground tolerant chip antenna design that will allow the reverse side of the PCB to be utilised for components etc.

We realise that ground plane will be severely limited and that custom tuning/matching will be required to achieve the best possible efficiency of a bad job. If a gound tolerant antenna is not available, then we will have to do the same process with the next best available detuning tolerant antenna.

Are you able to offer any suggestions?

Thanks and regards,

Gareth Pont

Answer 1

Hello Gareth,
For your application I would integrate the antenna in your system. An antenna which uses PCB, battery and other components as counterpart to the radiator.
Magnetic loop antennas like Weii are quite tolerant on human dielectric texture. However, they require a larger ground area for a good operation.
On electrical antennas you can only with space surrounding the radiator reduce the detuning effect.

Regards
Guenther