There are millions of people who are now living better lives, or living only because of medical implants like pacemakers. These millions of people also know their implants are not maintenance free as new surgery is required to replace batteries which can account for half the volume of the implant. This requirement of relatively large batteries is a critical flaw for these devices, but researchers at the Stanford School of Engineering appear to have found a solution.
Wireless power is nothing new, even for in-development medical implants. The problem is skin and flesh are very poor conductors, so the stuff between the implant and the transmitter block a lot of energy to the point of making the approach useless. That did not stop the Stanford researchers though as they developed a new model and found that, at the proper frequency, it is possible to penetrate the body with radio waves. That frequency is at 1.7 GHz which is high enough to let the receiving antenna be quite small (lower frequencies can also penetrate the body, but you do not want long antennas in the body).
At that high of a frequency, the antenna is small enough that the entire device for capturing the energy can fit on the head of a pin at just 0.8 mm in radius. This design also successfully beat the problem of antenna orientation, because being off by just a few degrees can cause power to drop considerably. The researchers have now applied for the patent on the antenna design and from there, we will see what the medical world does with it.