CAPITAL CURRENTS: Implanted Medical Device Communications
Is it the defense and intelligence community that is behind this?
In March, the FCC issued a notice of proposed rulemaking to allocate 24 MHz of spectrum in the 400 MHz range for low-power communications to control surgically injected neuromuscular microstimulation devices. This was in response to a petition filed by a biomedical research institute and was supported by medical researchers and rehabilitation experts.
The comments were the usual stuff – incumbent spectrum users telling why it was a bad idea and potential users giving favorable testimonials – with one exception. A comment came in claiming this was part of a clandestine government program to insert medical devices without informing patients, and then use them to inflict pain. Wow!
First, some background. In 1999, the FCC created a Medical Implant Communications Service for low-power, short-distance communications and allocated spectrum at 402-405 MHz. This has been used to control implanted cardiac pacemakers and defibrillators. This band is also used by other radio services operating at higher power, including radios used to communicate weather data, and the FCC rules say that the medical devices must not cause interference and must accept interference from other users.
In 2007, the Alfred Mann Foundation (AMF) – a medical research foundation – asked the FCC to allocate an additional 24 MHz at 400 MHz to accommodate operation of implanted microstimulator devices. AMF claimed that such devices could serve as an artificial nervous system in individual patients to restore sensation, mobility and other functions to paralyzed limbs and organs.
So with its usual alacrity, the FCC in March proposed to allocate 24 MHz of spectrum in the 413-457 MHz band (corresponding roughly to cable channels 56-62) for medical micro-power networks (MMNs). These networks would be used for the “transmission of non-voice data to and from medical implant devices for the purpose of facilitating functional electric stimulation and sensing, a technique using electric currents to activate and monitor nerves and muscles.” External master control units would operate at a power level of up to 1 milliwatt, and implanted devices would be limited to 200 microwatts. AMF said the 400 MHz range is the most suitable for radio frequency signal propagation within the human body.
Then the comments came in. First was a letter from the NTIA. The federal government operates land mobile radio systems in the 406-420 MHz band and numerous radars in the 420-450 MHz band. Some of the radars transmit with megawatts of power. The NTIA believes that radars could cause interference to MMNs, but mitigation techniques like error correction and dynamic channel switching should be tested for effectiveness. AMF replied that its devices include these techniques and work well. The devices employ error correction coding, dynamic frequency notching to detect and notch out narrowband interference, dynamic channel switching to avoid wideband interference, and precise timing and filtering to eliminate interference from radars.
Motorola also expressed concern about interference to MMNs, particularly in the 450-457 MHz range, which is heavily used for land mobile communications. Motorola also claimed that the 1 milliwatt devices could cause interference to land mobile communications. Similar concerns about interference to MMNs came from the radio amateurs and broadcast engineers. But AMF says that the low power of its devices spread over a wide bandwidth, plus a low transmit duty cycle of 0.05 percent (5 microseconds per 11 milliseconds) and other factors, will prevent interference to land mobile communications.
But then there was the comment from Dave Larson. Based on the comment – and on a lawsuit he filed in the U.S. District Court for the Central District of California and other material on his Web site – this is all a government plot. He claims that in 1997, AMF began using unwitting U.S. citizens as research subjects, without their consent, with funding from National Institutes of Health contract N01-NS5-2325, “Microstimulators and Microtransducers for Functional Neuromuscular Stimulation.” The research was publicly called "medical technology," but Larson claims to have learned it was a Department of Defense program to develop defense and intelligence applications that would be used to deliver electrical shocks and deprive targeted individuals of sleep.
He claims that the Mann Foundation was using the employees where he worked “as its pool of guinea pigs.” According to Larson, AMF implanted microstimulator systems into his body without his prior knowledge or consent. He says that occasionally AMF sends radio signals to his implants to inflict significant pain and shock. You can check his Web site for more details: http://larsonmedia.net.
So, is it the defense and intelligence community that is really behind this? I’m not allowed to tell.