As radio transmitters get smaller, they are turning up in the oddest places. Including people’s innards, with implanted medical devices now sending out reports on conditions inside. These include cardiac pacemakers and defibrillators that have monitoring and reporting capabilities, and devices used for diabetic glucose monitoring and control.

Two recent FCC actions will facilitate this ongoing communication through the skin.

One is an expansion of the ten-year-old Medical Implant Communications Service, now renamed the Medical Device Radiocommunication Service, or MedRadio. The new rules increase the available spectrum for implants from 402-405 to 401-406 MHz. External, body-worn devices are also allowed in the newly added 401-402 and 405-406 MHz segments.

Power is limited to 25 microwatts. Each device must monitor the frequencies it intends to use before it transmits, except that units can just blast away (if that is the right word, at these power levels) using 100 or 250 nanowatts maximum, depending on frequency, with strict duty cycle limits.

The transmitters are “licensed by rule.” This means they are deemed to be licensed even though the user does not actually have a license – just like CB radios. In fact, to get around a pesky statute that limits license-by-rule to just a few services, the implanted radios are defined to be CB radios. Breaker One-Nine, good buddy, and how’s the spleen doing?

The order adopting the new MedRadio rules is here.  

In a related action, the FCC issued a Notice of Proposed Rulemaking concerning “implantable neuromuscular microstimulation devices.” These would be multiple devices surgically installed in a person to communicate with each other, under control of an outside device, essentially operating as an artificial nervous system. Beneficiaries could include those with spinal cord injury, diseases such as multiple sclerosis, polio, cerebral palsy, and ALS, and combat injuries.

To handle these devices, the FCC proposes to make available one or more of the segments at 413-419, 426-432, 438-444, and 451-457 MHz. It also lays out ideas for operational and technical rules. The NPRM is here.

Maybe now men will finally get in touch with their inner feelings. By radio.