Help on designing a watterproof device with external world connection

[Sink0]

I am developing a project that is very similar to an actiwatch (wrist actimeter). There are several requirements, but the most hard of them is to be watterproof but still have an easy access external world connection. Also would be nice to have some way to send power in to charge a LIR2032 battery (lithium-ion). The size must be something very close to a sport watch. Looking for the off the shelf products i noticed that many actimeters use some sort of wireless commnication but still with a very compact size. A good example would be https://www.camntech.com/products/actiwatch-mini/actiwatch-mini-reader

Any idea on how is the communication of that device?

Another product that is very similar to what i need (but still without all the sensors i will use) is the philips actiwatch (**broken link removed**). It got a dock to make a connection AND recharge the battery.. any idea on how to recharge a battery wirelessy and keep a very compact size and reasonable cost?

Any sugestions are apreciated.

Regards,

Luis Filipe Rossi

 

[wa1kij]

An RF signal (it would have to be microwave) strong enough to be rectified so as to charge the battery. The signal could be modulated to input information to the device, including (most importantly) that the transmission is about to pause so that the device can transmit its own data.

 

[Sink0]

Any simple way to implement that?

Thank you!

 

[tpetar]

Use IR link.

 

[wa1kij]

Any simple way to implement that?

Thank you!

No, unfortunately.

---------- Post added at 21:02 ---------- Previous post was at 20:52 ----------

tpetar has a good idea. use IR to transmit data from the device, and microwaves to power it. antennas are cheaper than photovoltaics, and LEDs are cheaper than transmitters.