At the University of Michigan engineers have been working on developing tiny electronic devices that are small enough to be injected through a syringe. Their latest development is a miniature antenna that can transmit and receive data in vivo at distances up to one foot. It uses magnetism instead of electromagnetic radiation because the body attenuates the latter very strongly. This is an important development that will help advance the field of implantable devices, making them smaller and more capable, as well as allowing external monitoring devices that connect to the implants to be worn not just above the implant sites.
Here’s a video report from U of M on the new antenna:
https://www.youtube.com/watch?v=t7Ixd_KE_10